We are saddened to report that Professor Dornfeld passed away in March, 2016. If you enjoyed his blog, please consider making a contribution to either of two funds at UC-Berkeley that have been established in his memory.

David A. Dornfeld Graduate Fellowship
David A. Dornfeld Scholarship

Thursday, December 23, 2010

Humbug?!


Or, considering our future

One of the things that forms part of our holiday routine is watching the Alastair Sim's version of Dicken's classic "Christmas Story" (see You Tube). Scrooge (the character Sims plays) is visited by three spirits on Christmas Eve (in his dreams) who show him the errors of his past, present and potential errors of his future if he doesn't "wise up" to the value of looking out for others. Scrooge, as you may recall, is a wealthy self-centered business man who was representative of some folks in Dicken's time in London in the 1850's. As a result of his spirit interactions Scrooge comes around to the betterment of all he comes into contact with (specially his clerk Bob Cratchit and his lame little boy 'Tiny Tim') and doesn't really lose much as the cost is not large compared to the benefits in his generosity and kindness.

I've often thought about how this movie might be remade with the concept of a sustainable world and the impacts individuals and companies make on all around them and their environment. Corporate sustainability reports are one way in which companies try to show, as Scrooge did, that they "get it" and it is not too late to embrace this bigger view of the world.

Lester Brown compares the change in thinking needed to that akin to the notion that the earth revolves around the sun and not the other way around - he is called "an environmental Paul Revere" (see Wikipedia). He notes that we used to consider the environment as part of the economy but it is really that the economy is part of the environment. Wikipedia quotes him from a speech in 2008 stating ' "indirect costs are shaping our future,' and by ignoring these, "we're doing exactly the same thing as Enron- leaving costs off the books. Consuming today with no concern for tomorrow is not a winning philosophy."

He could very well be one of the spirits of the future to visit our modern day Scrooge.

Other "spirits" include Paul Hawken (and his book The Ecology of Commerce, Collins, 1993 - a book I assign for reading in my sustainable manufacturing class). He gives (p. 139 of that book) as a definition of sustainability "an economic state where the demands placed upon the environment  by people and commerce can be met without reducing the capacity of the environment to provide for future generations...your business must deliver clothing, objects, food or services to the customer in a way that reduces consumption, energy use, distribution costs, economic concentration,soil erosion, atmospheric pollution, and other forms of environmental damage. Leave the world better than you found it."

Our modern day Scrooge wakes up to realize that if you are NOT presently at a sustainable state … then you need to meet the demands  of today without compromising our ability to meet the demands of the future by reducing the environmental load/unit of commerce to offset any increase in unit production so as to achieve a sustainable state over time.

If you are presently at a sustainable state…then you can meet the demands  of today without compromising our ability to meet the demands of the future. This is a net zero impact.

That is, in the words of Hawken, your business must deliver clothing, objects, food or services to the customer in a way that reduces consumption, energy use, distribution costs, economic concentration, soil erosion, atmospheric pollution, and other forms of environmental damage at a rate greater than the normal growth in consumption would require. Business must have a “net positive impact.”

That is a challenge to do while staying profitable but, as we've seen in postings in the past, not impossible and the tools to help do this, specially with respect to manufacturing, are growing in number and capability. Our so-called technology wedges are one set of tools.

Hawken and Lovins, in Natural Capitalism (Little Brown, 1999, another book I assign for class reading) state in the preface p x-xi. “The best solutions are based not on tradeoffs or “balance” between these objectives [economic, environmental and social policy] but on design integration achieving all of them together - at every level, from technical devices to production systems to companies to economic sectors to entire cities and societies.”

They go on to state that, ala Scrooge and his spirit visitors, “Without a fundamental rethinking of the structure and the reward system of commerce, narrowly focused eco-efficiency could be a disaster for the environment by overwhelming resource savings with even larger growth in production of the wrong materials, in the wrong place, at the wrong scale, and delivered using the wrong business models.”

That's what we've been talking about.

One way to "rethink the structure and reward system of commerce" to bring the external costs firmly into play is cap and trade.

As I heard on NPR the other morning while going to my office on campus "the whole world is watching California."

This is part of the 2006 Climate Law, called AB32, designed to give companies who generate large volumes of green house gases the "incentive" to emit fewer of those. And, interestingly, this is designed to move from impacting the big emitter, like oil refineries and some factories, "downstream" to the consumers of the products of those industries. Like me driving my car if it uses gasoline from a refinery that emits green house gas in this fuel production.

Which means I'll pay for this. Which means, I expect, I'll have even more incentive to look for vehicles that have improved performance in fuel economy or use none at all (but power companies are also on the list so be careful - who is most efficient in creating energy with least impact will be the question?! Remember the "impact equation"? Impact/GDP - this is it in practice!). This will impact automakers and many others in the supply chain as well.

And, although some take issue with this, the impact on the economy of California (eighth largest in the world if California was considered an independent country) is expected to encourage job growth and technology development.

More to come on this next time.

For now, my best to you for the holidays and a happy new year to all or, as Tiny Tim says, "God bless us every one!"

Friday, December 3, 2010

Tools for assessing impact


Or, are we "doing the right thing?"

The last couple of postings have focussed on how to insure we can measure, and then take credit for (or get some credit for) changes made in a process that create a positive impact in terms of life-cycle impact or consumption.

This came up with reference to a discussion on net present value (or NPV) which is a way to estimate the the degree to which an improvement today leverages benefits into the future. The goal is to identify investments that can be leveraged in the future for big returns.

This brings up the question - what are some methodologies for making these assessments? In earlier postings (very early, in fact, see August, 2009 posting) we discussed rates of return for reductions in green house gas emissions, or water use, or energy use.  But, how can we identify where to apply technologies (and, more importantly, what technologies to apply) for driving these reductions?

And - apologies in advance - I've been slow to get this posting ready due to end of the year academic activities and this will be along one!

One neat technique that came to our attention for meeting this challenge is called a "pinch analysis." (see wikipedia for a good description). This came up in a recent project we were doing for a major European automotive manufacturer and the very energy intensive process they were using to clean precision components (including engine blocks and heads) after production to remove contaminants. These contaminants could lead to assembly problems and performance issues in use.

First let's look at what pinch analysis is, then the process we applied it to and then the results. (And put your thinking cap on as this will get technical fast!)

Wikipedia describes a pinch analysis as "a methodology for minimizing energy consumption" that was originally developed for the chemical industry. Wiki includes this nice summary of the technique -

"… process data is represented as a set of energy flows, or streams, as a function of heat load (kW) against temperature (deg C). These data are combined for all the streams in the plant to give composite curves, one for all hot streams (releasing heat) and one for all cold streams (requiring heat). The point of closest approach between the hot and cold composite curves is the pinch temperature (pinch point or just pinch), and is where design is most constrained. Hence, by finding this point and starting design there, the energy targets can be achieved using heat exchangers to recover heat between hot and cold streams. In practice, during the pinch analysis, cross-pinch exchanges of heat are [often] found between a stream with its temperature above the pinch and one below the pinch. Removal of those exchanges by alternative matching makes the process reach its energy target."

This example comes from the MS Thesis of Mr. Saurabh Garg, titled "Solid Particle Contaminant Cleaning in the Automotive Industry",  and done in my lab at Berkeley in Spring 2010. The motivation for this project was the large amount of energy consumed by the cleaning process that is not only a production cost constraint for the automotive industry in the wake of ever increasing energy prices, but also leads to a significant environmental footprint in terms of indirect greenhouse gas emissions. Garg noted that the severity of this impact depends on the energy mix of the geographical area and the impact created by the sources of energy production.

The objectives of the work that form the basis of applying the pinch analysis were:

- characterize various fluid flows in the process and in external circuits in terms of important parameters such as steady state flow rates, and temperature
- optimize the energy flows in the system to ensure maximum process-to-process heat recovery potential
- propose distribution of the net load on external utilities to minimize the overall heating and cooling costs, and
- analyze and compare the energy requirements of a standalone system of cleaning machines vs. that of centrally heated and cooled machines in a manufacturing assembly line.

So we are dealing with flows of fluids at different temperatures - a relatively common process characteristic in manufacturing (think painting, heat treating, washing, etc.) Not surprisingly, this will involve some simple thermodynamics.

The basic concept of a pinch analysis (as defined above) is represented by the diagram below, showing the temperature - enthalpy rate for a process stream in manufacturing. If you need some brush up on your thermodynamics, check the wikipedia discussion on enthalpy. Enthalpy is, basically, the  measure of the total energy of a thermodynamic system. Wikipedia explains that since "the total enthalpy, H, of a system cannot be measured directly … change in enthalpy, ΔH, is a more useful quantity than its absolute value. The change ΔH is positive in endothermic reactions, and negative in exothermic processes. ΔH of a system is equal to the sum of non-mechanical work done on it and the heat supplied to it."  The figure below summarizes the basis of the analysis.



The analysis starts by representing all the process streams in the domain of analysis on a temperature-enthalpy rate (T- ΔH) diagram where the vertical (y) axis represents the temperature scale while the horizontal (x) axis represents enthalpy rate. Each process stream is represented by a straight line on this diagram running from the stream inlet temperature (Tin) to the stream target temperature (Tout). For a process with a series of process streams that comprise the whole operation, you make one straight line for each stream in the series. The term ΔT stands for the difference between two temperatures.

Since any horizontal distance on the x-axis represents a difference of enthalpies in which we are interested, the absolute values on the x-axis are insignificant. It is precisely for this reason that the composite curves can be translated horizontally on a T-ΔH diagram, without affecting the process stream.  The slope of any line representing a process stream on a T-ΔH diagram is given by 1/(mass flow rate x Cp). Here Cp is the specific heat of the fluid.

For heat exchange to occur, the hot stream cooling curve (hot composite curve) must lie above the cold stream heating curve. (cold composite curve). Because of the ‘kinked’ nature of the composite curves, they approach each other most closely at one point defined as the minimum approach temperature (ΔTmin). The point of minimum temperature difference represents a bottleneck in heat recovery and is commonly referred to as “pinch” as defined earlier by the Wikipedia reference. The area of overlap between the composite curves represents the potential for process-to-process heat recovery. As stated before, horizontal translation of the curves will vary ΔTmin such that at one particular value, the overlap shows the maximum possible scope for heat recovery within the process. At this value the requirement for external hot and cold utilities, as represented by the hot and cold end overshoots of the composite curves, is minimum. However, the maximum process recovery is only a theoretical concept and practical design challenges and cost considerations limit this value as illustrated below.


As seen in the figure, external energy costs increase linearly as the ΔTmin increases. This is because at low temperature difference, the energy transfer process is more efficient and the in-process energy recovery potential is high because the hot and cold composite curves align nicely with each other. In other words, the potential for energy recovery decreases as the composite curves move apart (increasing ΔTmin).

Ok, so how was this used in the automotive cleaning example? The T-ΔH diagram depicting the hot and cold composite curves for the existing cleaning process (flows of hot and cold fluids at various temperatures) is shown in the figure below. Temperature is along the vertical axis (degrees C) and enthalpy (in kW) is along the horizontal axis. The figure was constructed following the procedure described above (and you may need to 'click' on the figure to see all the detail.)



The figure shows that there is a good potential for energy recovery through process-to-process heat exchange, as shown by the green shaded region. The pinch, in this case, is defined by an extended region and not a single position, having a minimum temperature difference of 3 degrees C.

The next step is to propose solutions to "recover" this energy and evaluate whether or not they are feasible economically and, also, what the potential environmental impact will be. A suitable heat exchanger was determined based on the area of heat exchange needed to accomplish the energy recovery. Then, using an economic analysis the potential return of the investment was determined. The figure below compares the total annual energy costs (based on heating and cooling alone) for the proposed retrofit design of the cleaning process based on an improved process-to process


heat exchange optimization vs. the current costs based on the existing design of the process. It can be seen from the figure that beyond the initial 3 years when the capital cost will be completely paid, the net difference between the operational energy costs of pinch-optimized retrofit design and the existing design is worth a savings of 84,500 Euros annually.

Further analysis resulting in considering adding a heat pump to recover some energy due to changes in fluid pressures also. That was good for another 20,000 euro savings annually after the payoff (3 years).

Finally, what about the environmental payback?

Garg includes this analysis as well. The use phase emissions for the existing cleaning process can be attributed directly to the impact created by the consumption of process electricity, and the heating and cooling energy. The total impact for each of these three forms of energy consumption can be calculated by simply multiplying the total energy requirement in each case, with a conversion factor that expresses the impact (kg CO2) per unit kWh based on the source and quality of that energy generation. For example, for a unit (kWh) electricity consumption, the corresponding GWP impact is roughly 0.649 kg CO2 equivalent based on the energy mix of Germany where this facility is located. The same is true for cooling energy, as the cooling is achieved through a refrigeration cycle that involves electricity consumption. For the heating, high temperature steam is used, whose production is linked to an equivalent impact of 0.204 kg CO2 eq./kWh.

Based on the above numbers, the use phase impact generated by the existing cleaning process is found to be 2335 MT CO2 per year. Because of the reduced energy consumption due to pinch optimization, the net impact due to the optimized process is much lower, about 1388 MT CO2 eq. per year - a "savings" of almost 1000 MT CO2 eq. per year!

However, the capital investment in the form of heat exchanger devices will also cause a one-time (fixed) impact, which can be evaluated using, for example, an Economic Input-Output Life Cycle Assessment (EIOLCA) database (e.g. from Carnegie Mellon University).  The EIO-LCA analysis for the heat exchanger was used for the given application and predicted an impact of 100 MT CO2 eq. So that is the "embedded" impact of the proposed switch and any improvement needs to be greater than that at the minimum.

Since the reduced impact, almost 1000 MT CO2 eq. per year, is substantially greater than the one time 100 MT CO2 eq. hit due to the production and installation of the heat exchanger we can safely say the GHG return on this investment is pretty good!

There is even better news. This is one cleaning station of dozens in this large automotive facility and, perhaps, hundreds throughout the company. The potential for larger impacts as more are retrofitted, with the same economic and environmental impacts, is tremendous. Talk about a great technology wedge!

And you can use this in your net present value evaluation also.

I'll let you chew on this long and detailed discussion a bit! But, the point is that there are a lot of existing tools out there that, carefully applied with solid engineering logic, can make a big impact on both bottom lines - cost and environment.

Wednesday, November 17, 2010

Leveraging all your resources


Future planning/future rewards

A number of items passing across my computer screen (or my ears from the radio) have prompted an additional posting on "leveraging" following our last blog on leveraging manufacturing.

These are, in no particular order, the continuing development of the Chinese high speed rail network (as reported on NPR the other morning), recent e-mails among a few "green friends" on the need for, and feasibility of, inclusion of influences other than economic terms in net present value (NPV) calculations, and a discussion I had recently with some "design" folks at a meeting on how a major company can include green manufacturing "awareness" in its products and get some recognition of this from the consumer.

These sound unrelated - but, I will now try to string them together! And apologies in advance if this sounds like rambling to you.

Let me start with the NPV discussion. This came up due to an article in a trade press basically stating that, since "green technologies" really only have positive net present value due to subsidies they cannot really drive economic recovery or create "high value jobs." This was presented as part of a discussion as to why we will be better off without cap and trade.

So, first, what is NPV? Referring to our old friend, Wikipedia, net present value  is "simply the present value of future cash flows minus the purchase price." It is a means to take expected future cash flows from an investment, usually a series of expected cash inputs over time, and convert them to an equivalent sum (present value, PV, or present worth, PW) based on an assumed interest rate or growth rate over the time of the future flows. Sort of, if you had this amount today (present value), and invested it over the same time period, it is the accumulation of value you'd realize over the amount started with.

If the NPV is greater than zero, the investment will yield positive results and may be worth the risk of investing. As Wikipedia says, "NPV is an indicator of how much value an investment or project adds to the firm." The assumption is, then, that if the NPV is zero, or less, the investment is not worth it.

So, now we throw in environmental considerations, or carbon footprint, or some other metric of impact or consumption, These are hard to monetize so the impact of these potential "rewards" cannot be easily determined. So, some say, we should not consider them in our calculations of investment and only go with those costs that can be solidly determined.

So, since we cannot estimate the "value" of reducing the carbon footprint of our process, or product, we cannot really determine whether the NPV of any investment which has the effect of reducing the carbon footprint is worth it. And, this brings cap and trade into the cross hairs. Cap and trade is a market-based approach that uses economic incentives to drive pollution reduction by steadily reducing the allowable amount of pollution that can be emitted. The idea is that if you are successful in reducing pollution below your allowable level, you can "sell" your excess allowance to someone else who has not yet been able to reduce their pollution.

And this is, to some, an artificial subsidy to some technologies that reduce pollution that cannot be justified by a reasonable economic analysis, like NPV.

The challenge is, can you include environmental metrics into NPV?

This was originally brought to my attention by Ralph Resnick of NCDMM in a note to a few of us asking whether or not we could include sustainability metrics in NPV. One response from John Sutherland, a professor at Purdue University and a leader in green manufacturing, referred to a great article in Forbes from June 2009 on "Calculating the true cost of carbon" by David Serchuck. This article offers a balanced and rational (to me!) explanation of carbon cost evaluation and the value of carbon taxes in an economy to drive CO2 reduction and technology. And the article puts an average price of $20 per ton of carbon dioxide.

The real question is - how do you value risk? And, then, how do you figure this in your NPV calculation?

Most folks I talk with, over a wide range of companies, see the potential risks associated with driving full speed off the "business as usual cliff" as real. Recall our recent discussions about water, rare earth metals, etc. This is all part of the equation. What is it worth to you to be able to reduce your carbon footprint and is the investment needed to do this worth it?

One common proxy for carbon is electricity (or rather one common proxy for electricity is carbon!). You can calculate the cost of electricity. You can determine the impact of your use based on where you are and the mix of fuels used by your local utility. So, we can use that for NPV.

You can estimate the impact of regulation on the cost of your product if we expect some areas of the world (and California) to start to track the carbon footprint of your product and, maybe (probably) tax you for excessive carbon use. This already occurs in France when you buy a car that has a gCO2 equivalent/kilometer travelled value less than a prescribed level. So, I can use that in my NPV for transportation.

There are probably more. We'll work on it.

NPV is a way to estimate the impact of future benefits in today's terms. Or, put another way, the degree to which an improvement today leverages benefits in the future.

So, what about the Chinese trains? The  NPR program talked about a new high speed train that cut the travel time from Shanghai to Wuhan to just 4 hours. It used to take 10 hours.  Wuhan is a rural area with lower costs of operation (by 50%) than in Shanghai nearer to the coast. Companies are moving there now (and these are international companies) due to the supply of labor, lower costs of operation (like living expenses for employees and, yes, local incentives) but accessibility due to the train. And they mentioned the investment in high speed train networks in China which will create a high speed rail network with more kilometers of track than the systems of the rest of the world combined.

And in US, some recently elected governors are refusing to accept Federal stimulus funding to build high speed high speed rail networks in their states.

In another e-mail exchange on some common research collaboration on energy efficiency and resource effectiveness we had a go around on the meaning of terms. John Sutherland made a simple definition that is worth sharing -  "In lay language, efficiency is "doing things right," and effectiveness is "doing the right things."

That's a great way of looking at investments that can be leveraged in the future for big returns - like high speed rail for example with big returns on impact/unit of distance travelled.

Finally, conversations with "design folks."

One of the discussions was on the motivation that companies (and societies) have for "doing the right thing" even if it is not possible to fully compute the benefits today. Sounds like the NPV discussion!

I was chatting with a particularly clever designer and we came up with a neat "app" for your smart phone or pad computer - "text messages from the future." Meaning, some algorithm for sending you, extemporaneously, a hypothetical text message from some friend (or relative) far in the future commenting on their life experience, or job or some other topic - just like you get text messages from folks today.

We thought of one - "Hi great-great-grandpa, wish you had cut down on your CO2 emissions 50 years ago; bought a new respirator today and my sister just moved to a great ocean front place in Savannah." LOL (not).

What do you think are likely text messages from the future?

We'll get back to more on green technology next time. And, let me know if you have ideas about calculating the leverage effect of your green technology wedges.

Thursday, November 4, 2010

Leveraging manufacturing for a sustainable world


Or, more beef!

I recently attended a conference on high performance manufacturing in Gifu Japan focussing on a variety of technical advances to push manufacturing ahead in the face of increasing competition, rising costs, difficult to process materials and changing requirements due to advanced product designs. A sub theme of the conference was energy efficient manufacturing.

One of the keynote speakers was a senior managing director of Toyota in Japan. In his presentation, in which he concentrated on the production of hybrid vehicles, he covered a number of manufacturing challenges Toyota was tackling with respect to getting more performance out of the automobile components. His examples ranged from magnetic elements for motors (which they stamp and assemble from materials with decreasing concentrations of rare earth metals!), to braking/energy recovery systems, to battery storage elements, to other power train components a heat recirculation system that shortens engine warmup time - all boosting fuel efficiency.

This work at Toyota tracks the performance improvement discussed in the last posting but, this time, for electric motors and systems and not internal combustion engines. The result is systems that hold a larger charge for a longer period of time increasing the range of the vehicle without engine assistance and, thus, dramatically improving vehicle performance.

A major portion of the improvement cited by Toyota for reducing CO2 emissions are due to merging (consolidating) production lines and discontinuing processes. This means looking for ways to remove, or eliminate, process steps in manufacturing by developing new technology with better capability to convert materials (recall that manufacturing is basically "shape transformation") with fewer process operations. Or, eliminate them altogether.

This resulted in a total annual CO2 emissions of the company to 1.22 million tons - a reduction of almost 10% since the previous year (see their 2010 corporate sustainability report (CSR), page 29 for details).  The per vehicle CO2 emission from production was down a bit also - but this could have been greater reduction except for the downturn in sales. Leveraging manufacturing!

Other companies, in the regular paper sessions, reported on their efforts to improve performance of their products and cited the impacts of their products in use. A paper by Mori Seiki engineers started out listing an estimate of the power consumption/green house gas emissions of their installed base of machines worldwide as an indication of the potential for improvement in machine operation and process improvement. This will serve as a basis to track the impact of their new machines introduced to the market which will, presumably, offer substantially reduced energy consumption (and hence green house gas emission). The goal is 40% reduction!

My immediate reaction was  that this is a bold move to "own up" to the performance of your product (even in the customer's hands) to establish a base line of performance. I was reminded of Toyota who list the cumulative savings of CO2 the 2.5 million hybrid vehicles they've sold compared to equivalent gasoline powered vehicles (Toyota CSR, 2010, page 24). This provides a baseline for measuring improvement. The figure below, from the Toyota CSR, shows this impressive reduction.

What if we could show this for all products as they evolve to more energy (or resource) efficient performance? You might think that for automobiles or machine tools this is an easy measure - impact per unit of product (which translates into reduced impact per unit of GDP from our discussion last time about the impact equation).

But not all improved performance can be easily equated to reduced impact per unit of GDP. There are many things that are sold in the world - but not all of them contribute productively to our life, or work, or well being.

It made me to wonder whether of not we could extend this kind of impact per unit to other products. What might the rules be for this (meaning what kinds of products would fit the analysis)?

It seems like it would have to be something that performs a function as a product, where function is a useful benefit, like transportation, or washing clothes or dishes or a tool used in production. Or, it must relate to quality of life (but not necessarily video games which use less energy or an iPod with a longer battery life for a charge).

What about food? One can't really deliver "more protein/unit" unless we eat fish paste (although, spending time in Japan one realizes just how many different forms of nourishment you can eat!).

I'm not finished thinking about this but if you have some ideas on extending the concept of reduced impact/product unit to a wider range of products let me know.

At the end of the conference we visited the Mazak Machine Tool Company's manufacturing facility. They practice something they call "done in one" which refers to using one machine in place of several individual process steps - basically multi-tasking on steroids. I discussed the potential of such approaches in a posting on "green balancing" last December. And this fits with Toyota's consolidating production steps/eliminating processes. Mazak gave an example of applying this to a crankshaft prototype production operation which went from 13 machines to 1, and a reduction of 2800 hours of processing to 8! Done in one. There is some info about this on their website.

So, if Mori Seiki (or Mazak) reduce the machine's consumption by 40% while reducing the product manufacturing phase impact as well by process consolidation or elimination, and then the product goes on to have a substantially improved fuel consumption (in the case of an automobile) with dramatically reduced CO2 emissions - that's leveraging manufacturing. And that's a technology wedge that takes a big bite out of the gap between business as usual and a sustainable level of performance.

And, if you'd like another neat example of eliminating process steps for dramatic improvement, "google" grind hardening or see an example on the Mori Seiki website. It avoids a heat treatment step which, usually, accounts for a substantial portion of energy consumption in production of precision hardened components - like shafts.

For the talk I gave at this Japanese conference I prepared a graphic to summarize the concept of leveraging manufacturing, see below.


It is a bit of a busy image but this shows the amplifying effect of manufacturing improvements (including the reduction in manufacturing phase impact or consumption) on the eventual benefit in product use. And, from my observation and evidence from other companies (like the Toyota and Mori Seiki examples) the characterization of small seeds of process improvement yielding large rewards over use is right on target.

More on this in the future I am sure!

Monday, October 18, 2010

Where's the beef?

Or, how manufacturing affects product use performance


First of all, this has nothing to do with meat clothing!

Remember our discussion a while back about "buy-to-fly" ratio? This was referring to the amount of the materials that actually end up in the product as one metric of material utilization efficiency (July 2, 2010 posting). The variation in that ratio was impressive with some of our more sophisticated products having very low ratios (structural elements of aircraft, for example, due to the challenging requirements of shape and strength.)

Another consideration is impact, or resource utilization, from manufacturing the product versus using the product. That is, the use vs manufacturing phase trade-off.

One of my research students, Teresa Zhang, had done an interesting analysis for a number of common products some time ago as part of her early work on her PhD in my lab. One of her charts is shown below and plots use phase resource intensity as a function of manufacturing phase resource intensity.
We see here that "things that don't move or need power to operate" like bridges, furniture, etc are dominantly manufacturing phase consumers of resources and, by extension, impact. Things that do "move and need power to operate" like automobiles, airplanes, etc. are use phase heavy. Interesting to note are the items that are close to the break-even 45 degree line. Personal computers overall, but not the chips in them, are a bit heavier in the manufacturing phase than use phase. Cell phones more heavy (but likely not if you include the embedded impact of the infrastructure needed to operate a cell phone network.) As usual, the details matter.

I was reminded of this during a presentation at a conference I attended recently in Germany during the presentation by a representative of the automaker VW in Germany. In the course of his slide show, he mentioned that, by their analysis, about 20% of the impact of a typical VW Golf A4 car came from manufacturing while 80% was due to the use phase. I had seen data on the GolfA3 (marketed from 1991-1999, also called the Polo) from some time ago and the comparison was similar. The figure below, from Volkswagen AG, and Harald Florin, PE Europe/IKP-University of Stuttgart, Germany (PE is the supplier of Gabi LCA software), shows the energy consumption during the manufacturing phase of the GolfA3 in Gj/auto.


Materials and part suppliers account for much of the embedded energy in the manufacturing phase. Machined components, such as the gear box and engine are a small percentage of the total (accounting for about 10% overall or about 25% with materials and parts from suppliers excluded).

If we look at the impact of the auto, including car production, fuel production and use phase, see below from the same source, we see that the fuel production and consumption in the use phase dominates all categories of emissions to air and water with the exception of dust generated by material production and casting of some components and painting of the vehicle and biological oxygen demand impacts on water.

More recent data I've seen from Volkswagen for the Golf A4 indicates that some improvements have been made (for example reduction of primary energy used in production, use and end of life due primarily to improved fuel consumption (a 20% improvement from 8.1 liter of fuel/100 km to 6.5 l/100 km for the gasoline engine).

In a posting on September 1st 2009 discussing the influence of precision manufacturing (and manufacturing in general) on environmental impacts I started out reviewing the basic impact equation (in terms of environmental damage, consumption, etc.) which is simply:

  Impact = Population x (GDP/person) x (Impact/GDP)

I commented that population grows with time and most countries strive to improve GDP/capita since that drives living standards, etc. The rate of consumption or environmental impact per unit of GDP is the "rate of damage" done as a result of the technology driving the growth in GDP and is really the only "knob" we can adjust to reduce impact. I noted that engineers are most effective at changing technology that affects Impact/GDP. To the extent we can reduce that impact we are, effectively, greening the process.

So, if we look a bit closer at the VW numbers, does this make sense in terms of reducing the impact/GDP? If we focus only on manufacturing phase we may not be encouraged - specially if the predominant impact is in the use phase. Let me elaborate.

Let's go back to our VW Golf example of 20% manufacturing phase impact versus 80% use phase impact. If we then think about the area I work in a lot, machining, and we assume about 20% of the manufacturing is machining or machining related, that gives us a potential for improvement of 20% of 20% or only 4% (and then if we get rid of all machining!). Let's assume that some of the snappier technology for improving machining efficiency is employed, say some specialty tooling material that reduces machining power consumption, and that is worth another 20%. Now we are down to .8% (20% of 4%).

Hardly worth the effort it would seem. Of course, if you are paying the electricity bill for the factory and this .8% technology wedge is added to a lot of others in machine operation it can add up to real savings. But, maybe still not impressive compared to use phase impacts. That is, over the full life cycle of the auto.

But, if we follow that logic we are leaving a lot of potential impact reduction from manufacturing "on the table."

In the precision posting I referred to above, I mentioned that a major German auto manufacturer has been working to improve the "power density" of some of its diesel engines over the past years and has seen an improvement of almost a factor of 3 in power per unit of displacement. That means, for the same engine size (displacement) they have managed to squeeze three times as much power out. Coupled with advanced fuel injector systems operating at very high pressures (once thought absurd) they see enhanced performance in a small engine - increased fuel economy, improved acceleration (due to reduced mass), and reduced emissions.

The chart below, from Daimler, shows the improvement in power density as a function of time. The different colors indicate the increasing pressures in the fuel injector systems feeding fuel to the engine.


This is impressive and seems to keep growing without bound. Same size engine, better fuel efficiency and power generation.

How can this be?

Precision manufacturing! The posting on precision gives an example of how this could work for a Boeing aircraft based on tightened tolerances allowing increased structural performance by better control on dimensions - resulting in lower weight components. It is similar for the Daimler engine whose performance is tracked in the graph above. With better tolerances, better surface finishes, better control of orifice size and shape on the fuel injector nozzles (with diameters on the order of 60 microns), tighter control on cooling channels and fluid flow in the engine due to enhanced casting techniques, and on and on, the engine (still working on the same old Diesel principles) performs dramatically better.

The "dog leg" in the chart above corresponds to the introduction of high performance, precision, manufacturing to the power train in the automobile. Similar improvements can be see in the transmission as well.

That is how to reduce the impact per GDP.

Manufacturing dramatically increasing the efficiency of fuel utilization in the internal combustion engine. The small percentage of manufacturing phase improvement has a giant leverage effect on use phase impact. Since the principal element in use phase impact of the automobile the reduction in consumption (due to increased power density of the engine) hits both the fuel production impact as well as the fuel consumption impact. In the Golf A3 figure for emissions, 90% of the CO2 impact was due to use phase (81% from driving and 9 % from fuel production). A doubling of the fuel economy, by manufacturing induced engine efficiency improvements, by precision machining and processing will essentially halve that (same distance driven) - or account for, in the case of the Golf A3, a reduction of some 16 tons of CO2. And if, in the process of manufacturing enhancement, we save most of our 4% impact from machining, that's .4 ton of CO2. So, for our .4 ton we get a return of 16 tons (a factor of 40!)

Now that's a return you can't beat.

OK, the calculation may not be quite that simple, but we are seeing the same order of magnitude of leverage effect here. And some may argue that this improvement can't be really counted as a greening effect of manufacturing. But, the motivation is enhanced performance which includes reduced impact. And it is due to manufacturing capability. I'll take that.

That's the true impact of greening manufacturing.

Finally, in an interesting follow on to the last posting about risks associated with material supply, specially for rare materials, Environmental Leader had a reference to a special report on "Eco-competitiveness: safeguarding profitability and the world’s natural resources"  by Sonny Masero Vice President CA ecoSoftware EMEA, CA Technologies (download report). The report addresses the challenges of managing a business dependent on, or influenced by, complex labor, resource, or material supply chains. One quote from the report summarizes it well - "Whether it is a skills shortage, a scarcity of raw materials or a lack of capital investment — every organization can be impacted by the shifting availability of external resources. Although businesses can do little to control such fluctuations in supply, they can put strategies in place to limit their dependence on scarce resources. Taking such a proactive approach is particularly important given the ongoing depletion of natural resources, such as oil, gas and water." Great reading!

Thursday, October 7, 2010

The rare earth "connection"

Or, be careful what you ask for


At the very beginning of this blog I presented a number of postings on "why should industry care about green manufacturing." (see post) This included to minimize risk to the business due to supply chain problems for critical resources needed for production or other material related disruptions (like no material available.)

I came across a perfect example of this while traveling recently (and, hence, had access to the Financial Times and International Herald Tribune - neither of which I subscribe to.)

The October 7th edition of the Financial Times newspaper has an article entitled "China tightens its grip on the production of rare earths," written by Leslie Hook. Rare earths are a group of 17 minerals that have strategic applications in a wide range of products and processes. And they are hard to come by (hence the name "rare"!)

Of the earth's supply of these rare earth materials, 97% come from China, 2% come from India, and the remaining 1% come from "other" countries. The US used to be a producer of these materials but the mining and refining can be highly polluting if not properly controlled. So, costs of extraction and processing and environmental regulations encouraged the movement of production to places with lower costs and, regrettably, more lax restrictions or, at least, compliance.

So what? The use of these rare earths is ubiquitous in a wide range of high tech products, processes and products designed to reduce the environmental impact of operation. For example, the FT article cites the following statistics for use:

- 25% in automotive catalytic converters
- 22% in petroleum refining
- 10% in lighting, televisions, etc.
- 11% in materials for polishing glass and production of semiconductors
- 20% metallurgical additives and alloys
- 22% other

It turns out that these rare earths are key to "performance enhancing" materials and products important to us. For example,

- the rhodium in catalytic converters helps to remove harmful by-products of internal combustion engines (even highly fuel efficient ones)
- rare earths in "super magnets" help improve (a lot it turns out) the performance of electric motors in terms of power output with respect to input power (and remember that electric motors account for a major portion of electrical energy used to day - both domestically and industrially; and a number of the greening technologies (wedges) we've been discussing rely on improved electrical motor performance.)
- improved refinery techniques for less polluting fuels
- flat screen TV's and monitors with reduced energy consumption, and
- optical products ranging from specialized lenses for lithography and imaging applications to the bazillions of little lenses in cell phones and small cameras that a whole generation of young people are using to capture inane images of goofy behavior that will be posted on their social networking pages to impress their friends (and in 'cyberspace' in perpetuity) so that later in life when they want to get that dream job at a major corporation some recruiter can find it and say - not impressed. (Sorry, I got a bit carried away there - you get the point!)

The Chinese recently, and I assume entirely coincidentally with the Japanese detention of a Chinese fishing boat in disputed waters and the arrest of its captain, shut off the spigot of rare earths to the Japanese. And, thus the FT article I am referring to. Japan is the largest importer of rare earth materials.

Risk, you say?

Let's follow the trail of bread crumbs.

Japanese seize Chinese boat in disputed waters. Disputed, I believe, because of uncertain ownership following a conflict over 50 years ago precipitated by a country trying to, among other motives, secure sources of natural resources and energy (I am not a historian - if someone thinks I am off on my analysis let me know!). The Chinese interrupt the shipment of rare earth materials, materials needed to produce high tech products and enable processes to reduce the environmental impact of other processes and products. Companies relying on the supply of these materials see the supply chain stretching taut - panic thoughts emerge in heads of these companies (or at least in the supply chain manager.) Fortunately, the Japanese release the boat captain and materials, again by sheer coincidence, begin to flow again. Whew, close one.

How can a company watch out for an extemporaneous event on the high seas that might, in domino effect, interrupt its production?

I am reminded here of a great book (and BBC series) from some years back by a British author James Burke called "Connections."  Using some fascinating history sleuthing to "connect the dots" he shows along several lines the connection between technology development (and what is driving it) and commercial and political development. One line he followed was the nexus between precision engineering and fabrication techniques, the invention of the sea-worthy chronometer (previous instruments had suffered from the rolling action of ships, temperature variations, the high salty humidity of the air, and lower quality of fabrication to render them practically useless on long sea voyages), and the spread of British naval and commercial influence worldwide. Seafarers could now reliably get there and back with improved navigation aids and maps - all synchronized by accurate time keeping. Sort of a 18th century equivalent to GPS of today.

Today, we could build a similar story about anticipating and reducing risk in manufacturing.

I've a lot more to say about precision manufacturing and sustainability impacts prompted by some recent conversations I've had and remarks heard at conferences by industry leaders. More on that next time.

In the mean time, the world may be flat as Thomas Friedman points out, but some folks are sitting on mountains of critical resources, and the view from up their is decidedly different! Fortunately, as one of the Japanese researchers pointed out in the FT article, scarcity and risk of supply interruption drive innovation - in this case to find replacement, more commonly available, materials to substitute for the rare earths or ways to more efficiently use them. And the more the costs of these materials go up (remember, the market place rewards risk and uncertainty with higher material prices) the more incentive we have to find replacements or, in the case of the US which has reasonable wealth of these still in the ground, resume producing them with all the necessary safeguards and procedures in place.

That's a business strategy to reduce risk.

Finally, a comment from some time ago from one of the readers is appropriate to this discussion. It is complicated, so I am repeating the whole comment, and question posed from Steve Hanna following the post):

Let's say company "A" learns of a green house gas (GHG) "hot spot" in its supply chain, say manufacturer "X" of widgets.  Company "A" is purchasing substantial widgets from company "X" whose attributable production equals 80 tons of C02 emissions annually. Company "A" finds company "Y" who produces the same quality widgets (and pricing) that only takes company "Y" 1 ton of C02 emissions per year to produce. If company "A" decides to dump company "X" for company "Y", it is indeed a good steward to the earth but does company "A" receive any credit (offset or anything) for mitigating C02 emissions within its supply chain via Scope 3 indirect emissions?

In other words, are their any incentives/credits for companies who lean out their supply chains? After all, company "A" is mitigating 79 tons of C02 emissions from entering the atmosphere by switching to company "Y"'s product over the energy-intensive company "X" product. Can any of the savings be attributable to company "A"s footprint?

This is a great hypothetical and although I am not an expert on all the associated counting mechanisms over the different scopes, I have to say that I believe Company A can take credit for the reduction due to this switch. Certainly if they are tracking this in their annual corporate sustainability report (CSR) they can count this. And, specially in California where we are looking at how to identify and then, I assume, count GHG in products coming into the state.

But, there may be other opinions out there. Let Steve and I know  (i.e. comment!). I also like the concept of a GHG (or any other) "hot spot" as a way to identify sources of loss or potential savings in a process, facility or supply chain. And, apropos our discussion above, how about risk "hot spots"?

More on this next time also.

One last item, Energy Secretary Dr. Steven Chu has a blog! He is in government now but remember he was a Berkeley professor before! In his recent posting he commented on the need to revitalize American manufacturing. He starts out with "Some people think our economy can run on white collar and service jobs alone, but they are wrong. We can and must make high quality products in America. We are on the verge of a new Industrial Revolution and I believe it will revolve around the greatest untapped opportunity of our time, clean energy."

I couldn't agree more. The potential for manufacturing technology to address the emerging clean energy market (he continues talking about battery manufacturing), greener manufacturing technologies and facilities, and greener products manufactured in the US is huge.

Tuesday, September 28, 2010

Don't be distracted by the shiny bits


Or, is there any there, there?

When ever I am thinking of what would be a good topic to build the next posting around I never have to wait long till something pops up. This time…the peculiar intersection of celebrity and the environment.

Maybe you did not see this (it was hard to miss if you read even the mainline press) but a "musician" (or actually performance artist) named Lady Gaga showed up at a music awards program dressed in a "meat dress." You have to read this to believe it as reported by Ecouture magazine website. So, standing next to Cher wearing something "cher-like" is this celebrity covered in thinly sliced beef. The article comments that "the American chanteuse’s Atkins-approved getup, [was] made entirely of slabs of tenderloin, strip steak, flank steak, and rump roast (about $100 worth of the cheaper cuts, notes one New York butcher)." Who says there is no innovation in the US?!

Normally I'd let this one drop without comment but the firestorm of comments about the "environmental impact" (what about mental impact?!) was interesting. Pundits reacting pointing out the tremendous impropriety of this getup with perspectives ranging from "people are starving and she's wasting meat" to "do you know how much green house gas emissions are contributed by livestock production?" (Turns out a lot - according to a UN Food and Agriculture Organization study reported a few years back - more than transportation.)

If one looks at climate change per ton of protein production (from the Ecouture article) she should have covered herself in peas or soy beans if she wanted to make an environmentally benign statement. Only lamb is worse than beef generating more than 100 tons of CO2 equivalent emission per ton of production.

The fashion industry has had a lot of problems finding the fine line between really sustainable products and the chic eco-fashion that looks good on paper (you know, organic cotton, recycled plastic, etc.) until you realize you could feed a family of 4 in many parts of the world for a year or more on the cost of the item.

Eco-not.

If you think I'm off on this, check out the Hungry Planet images posted on Time Magazine website showing what the world eats. The photos document the typical weekly food expenditures of a number of families around the world in local currency and dollars. The family in Chad spends $1.23 a week. Show this to your kids!

The first reasonable reaction to this whole event, the article and the response is - who cares?! When is the last time something truly significant, in terms of environmental impact (not withstanding the BP Gulf of Mexico disaster) received so much press? Wouldn't it be more useful (not to mention the environmental impact of all those computers on and users browsing the Lady Gaga article) to actually discuss things with a more potential impact?

This is actually sort of "green-washing" in reverse - meaning the trumping up of a minuscule environmentally impactful event or item with absolutely no potential to grow into something larger (do any of you see a trend to meat clothing?) into something important. This is almost worse than actual greenwashing (recall our discussion on this some postings long ago (July 10 of last year to be exact - see the post).

Just like it's wrong to overplay quasi-green (or non-existent green) aspects of a product or solution as part of the solution to sustainability, it is wrong to overblow a stunt act into something indicative of the future of the planet. Let's stay focused on what is actually something or, as they say, when "there is some there, there."

Also, just to clear any incorrect perceptions, I like meat (specially beef). I was born in Wisconsin and am happy to have farmers raising cows for milk and other uses in the food chain. My shoes contain leather. So, nothing against livestock here!

So, back to reality and some "there"!

As a follow up to our discussion about data flows (drinking from a firehouse), monitoring and dashboards for energy consumption, I mentioned that I visited the Bosch-Rexroth booth at the IMTS show the week before. They sent me some images from the display and this gives some substance to my "Google earth view of manufacturing" that has appeared a number of times in this blog (just search for the term in the box at the top of the blog page if you don't remember this.) At the lowest end of the "manufacturing view" was the machine with tooling and process details.

The figure below, from Bosch-Rexroth's MTX CNC Energy and Power Monitor for energy efficiency, shows the monitoring


strategy with the ability to identify the utilization, and losses, associated with power coming in at the bus, output to the motor, output to the mechanical shaft driving the machine tool (moving the workpiece relative to the cutting tool) and to track this in a dashboard, on an axis by axis basis including the consumption of auxiliary components. There is an article on this in the SME Manufacturing Engineering magazine of April, 2010 if you'd like some details. The figure below shows auxiliary consumption for hydraulics, fans/ventilation, cooling unit and spindle cooling.



With this level of detail associated with the process (what am I producing and how are the machine drives responding?) and the auxiliary components (when I'm not producing product what is my machine consuming? Is is worthwhile to shut some of this down while the machine is in changeover or idle?) the machine tool builder can consider alternate stratifies of machine operation and control, and the manufacturer can  (with suitable analysis tools) determine best practices for insuring part quality and minimum energy consumption.

Lots of data but a lot of digestion and presentation so we can handle the deluge...and make decisions.

Now this is worthy of some comments.

To end, I was reading the Economist (September 4, 2010) on a recent plane trip and they had an article titled "Ruses to Cut Printing Costs" with a byline that said "all kinds of technological tricks are being used to reduce the cost and environmental impact of office printers." I was intrigued. Turns out, people are doing all kinds of things to save resources which, for a laser printer (or ink jet), you can try to optimize "print vs toner" by choosing fonts which are thinner and use less toner or ink per character. The article quotes on source as stating that by switching to Century Gothic (which uses less ink) they saved $80/year/printer. The key was noticing that variability of ink/toner required per letter with different fonts!

Another company, a Dutch firm called Ecofont, came up with software to insert into fonts small holes in the letter that are not visible to the eye. This works best apparently on small fonts. They claim to be able to save 25% in the amount of ink or toner used. That's green!

And this is sort of the "office" equivalent of minimum quantity lubrication which reduces, dramatically, the amount of cutting fluid needed to machine a component. I mean reductions from thousands of liters to milliliters. We might discuss this some time in the future.

If your going to print the data from your firehose make sure it has holes in it!

And, finally, last, from the comment section, one commenter asked relative to my posting from the IMTS "did exhibitors or speakers address using the USGBC LEED program helping to provide assurance to end customers of verifiable improvements of manufacturing facilities?" Short answer, I did not see anything on this but, to be fair, was not looking for that angle. The focus of the show was on stuff in the building, not the building itself. Further, most manufacturers are just getting to grips with the operation, or use phase, consumption and not the embedded energy from materials, buildings, etc. used to produce the hardware. But that is coming.

Many companies have started working on the lighting, heating and ventilation, compressed air, etc. plant wide large scale energy consumers. But, there is much to be done. I'll check with some of my contacts to see if there are any examples of successful verifiable improvements. I am sure they are out there. Any readers can send me the contact info and I'll pass it on to the commenter or use the response section in the last posting  to respond directly.


Wednesday, September 15, 2010

Drinking from a firehouse, part 2


The greatest show on earth

This week I am writing from the IMTS in Chicago also known as the "greatest (manufacturing) show on earth" to paraphrase Barnum and Bailey. And it is a bit of a circus. Instead of rings you have several large halls chock full of the latest manufacturing technology (hardware and software) and every vendor who is anyone is here showing their stuff. Lot's of noise (machine and human), lot's of people, it's great.

So, what does this have to do with our firehouse analogy?

Let me elaborate. The "hidden" theme of this show is energy and resource consumption. The concern about energy monitoring, display and decision-making is pervasive. Not in the banner over the booth, but in the displays on the floor. Specially for the large control and motor/driver manufacturers like Fanuc, Siemens, and Bosch-Rexroth. They are all showing technologies for measuring and displaying energy data on controller or dashboards on computers.

Other companies are pushing the application of their machines and solutions to the growing alternate energy market - for example MAG is pushing production of wind and solar components, large and small, and OKUMA has a banner proclaiming "Solutions for Energy." Every one is seeing the push to reduce and the potential for market share in creating the solutions.

And why? Demand from customers, growing business opportunities and/or push back from people using their systems in production.

One of the people I have interesting discussions with about the trends of manufacturing and what's hot and what's not is a principal in a large high precision manufacturing company in the midwest. They have a range of clients from medical device to aerospace and the US Navy. To see their facility is to observe parts being made of tiny medical devices on a "Swiss" rotary transfer machine all the way to cowling components for surrounding the jet engines on the Airbus A380 giant airplane.

They also do work for companies like Johnson and Johnson and when I asked my friend if they are getting any serious push from their customers on energy he gave me a resounding YES!

Johnson and Johnson have a statement on their website, amongst a list of their expectations for the company's environmental performance, that their goal for External Manufacturing (ie my friend's company) is "100 percent of external manufacturers in conformance with Johnson & Johnson Standards for Responsible External Manufacturing by 2010." To date JNJ state that they have "shared our Standards and/or integrated these standards into formal contracts with more than  80 percent  of our external manufacturers by year-end 2007." Performance on the environment in the contract with their external manufacturers!

This means data…data on energy consumption of manufacturing…which means data from machines on performance cross linked to parts…meaning energy data linked to steps in the production of the part including on a line by line basis for the program code driving the machine tool in the case of material removal processes. This adds up to a lot of data - the subject of the last posting.

Recall that we had estimated that sampling energy data values for a "medium sized facility" for a day (here meaning 25 CNC machines, 10 programmable logic controlled machines and assorted other handling and line equipment with 8 data sources per machine at a sample rate of 5 hertz) would yield a data stream of 86,400,000 data points each day. And that if we added the other sources, we'd likely end up with 100 million data values a day to deal with.

So, let's continue our discussion from last time. Data can be related to events and information associated with those events. Thus, data can be understood as something that occurred either at a specific time or over a range of time. In manufacturing systems, events can be a numerical value (for example, the instantaneous power consumption at a specific time) or can be a type of annotation (for example, the alarm state of the machine tool over an interval). Complex events are abstractions of events that are created by combining simple events. For example, based on simple events pertaining to the tool position, the instantaneous power consumption, and the machine tool’s program in machining a part, we can create maps linking power and stages of part production.

The paper I referred to in the last posting describes what is called "events stream processing techniques" that include rules engines (RE) and complex event processing (CEP). These techniques can be used to create higher level abstract events and reason on them by pattern matching and identification. The figure below is an example of software architecture for temporal analysis. This spans multiple data


inputs from several devices, standardized data bus (e.g. MTConnect), and use of rules and complex event processing to create these "maps linking power and production."

My friend can use this to answer J&J's concerns about how much energy they are using to create the products they make. And, we can extend this to water, other resources, or whatever the customer wants tracked. And, knowing consumption is the first step to reduction.

The paper from part one of this posting went on to show the results of a case study applied to an energy
monitoring and analysis framework using energy consumption and process parameter profiles from machining experiments.

But at the show, Dr. Vijayaraghavan (the coauthor on the paper we were discussing in the last posting on data handling) and his company System Insights had a neat demo in the Mazak booth showing the real time implementation of this. On a website you can see, for a number of Mazak machine tools of varying sizes, the instantaneous power consumption. If you click on one of the machine icons you go to a "Mazak Energy Dashboard") for the machine (see below) and get the data, over time periods of


whatever you like for the operation of the machine. You can see total energy use (in kWh), energy cost (for the location you choose - US, Japan, Germany or, in the US, state by state), and "savings" relative to a benchmark machine test in the categories of energy, money (based on cost of energy), Co2 emission equivalent (based on the energy to CO2 conversion for the locality's energy mix) as well as that equivalent in terms of Al cans saved, miles of auto driving or use of compact fluorescent lamps. And, it has in the lower right hand corner an cool real-time power meter readout.

A further chart from that machine window shows real time power plot over time and summary info, shown below for the Integrex i200S Mazak machine tool. The summary numbers are a bit

different in the two figures as I accessed the data on the website at different times as I was preparing this posting. If we dig deeper, as in the figure last posting September 6th on examples of analysis across temporal scales, we can see the ability to correlate power with specific machine motions. That is next on the dashboard.

This starts to convert our firehouse of data into rather manageable mouthfuls!

I visited the Bosch-Rexroth booth and they were showing similar information albeit, in this case, from a specific set of servos driving a machine simulator.

It's happening. Data flows will increase. Are you thirsty?!

Monday, September 6, 2010

Drinking from a firehose


Or, data collection for energy and resource monitoring

I mentioned last posting that I was attending a manufacturing conference in Italy the end of August and that there was a lot more discussion about some aspects of green and sustainable manufacturing - at least efficient use of energy.

This is supported by business surveys and comments in the business press reflecting, I assume, the interaction with business folks "in the know" on such matters. A recent McKinsey special topics report  titled "The next environmental issue for business" gives some interesting statistics on what matters most to business. The report actually was focused mainly on biodiversity and the importance that holds i the minds and hearts of business. We can get back to that topic in the future (and read the report…it is interesting).

I was intrigued by the more general data given in the McKinsey report on issues of importance to business (and based on a responses of almost 1600 survey takers). The top vote getter was "climate change/energy efficiency" coming in at 43%. next in line was "waste/pollution/recycling" with 42%. Following that was "water scarcity/water quality/sanitation at 27%. There are 10 other categories of issues ranging from data privacy to global public health. And, "biodiversity" was 10th on the list. Another "environmental" related concern was toxic materials at 14%. (Note: the respondents ranked a number of issues; so, the percentages will not add to 100!)

I was pleased to see the top three as close to our topic of green manufacturing since they deal with, in order, energy we use and its impact, things we throw away/waste and things from the environment used to make our product besides energy - here water.

Water is often overlooked in all the concern about energy. Not by everyone however! Caterpillar has a goal of "hold[ing] water use flat" as they increase their business listed in their 2009 Corporate Sustainability Report. The website (link to report) gives a short discussion of Cat's plan to determine the "true cost of water" and includes the following statement:

"Without good data it is impossible to justify the cost of water-saving initiatives."

They go on to explain how a program in 2009 at one of Caterpillar’s American plants launched a program "to quantify how much water it was using in its different processes, and the costs associated with water use in each process – including water bills, chemicals, labor, maintenance and energy. The project helped the plant identify its most expensive water processes and associated costs and justified the capital expenditure needed to implement savings."

They plan to extend this program to other Caterpillar facilities in 2010.

Good data … and plenty of it!

Ditto for energy, other resources, etc. throughout the factory.

In the manufacturing conference in Italy I attended, the CIRP General Assembly, I presented a paper co-authored with one of my recent graduate students, Dr. Athulan Vijayaraghavan, titled "Automated Energy Monitoring of Machine Tools." The full reference is "CIRP Annals - Manufacturing Technology 59 (2010) 21–24." (Let me know if you'd like a copy.)

This paper laid out the immense challenges associated with trying to acquire, store and process the streams of data from a variety of machines in a variety of systems throughout a variety of factories. This is done in the hope of, first, understanding where energy (in this case) and other resources (like water) are used and then how to meet the kind of goals the Caterpillar folks are aiming at. This means, understanding the nexus between process operation and resource use to be able to find ways to minimize the use per unit of output. That is, decouple the process and resource equation so we can effectively reduce the "impact/GDP" discussed a few postings back to reduce overall impact of manufacturing.

We focussed on only the machine tool…but the approach can be extended much more broadly.

If you think about making this "connection" between resource consumption and process, you need to first determine the rate of data you need to make the link. For energy, this can range from parts of seconds to hours.

You may recall our discussion some postings ago (January 21, 2010 to be exact) about "temporal vs spatial" aspects of manufacturing. We can create a similar diagram to illustrate this discussion of data rate


demands for tracking energy and resource use. The figure highlights the data rates for machine tools but, for broader sections of the enterprise, you can see the time scale also. The idea is you need sufficiently high data rates to capture the process effects or variability you are trying to associate the use with. Then, we can see how adjusting those parameters or variations can yield savings (without, of course, sacrificing quality or cost.)

Here is another illustration from the paper showing the use of energy in the context of the manufacturing process. The objective is to have data rates "tuned" to the process so one can extract such

            Time scale of data collection for energy use in the context of manufacturing process

information as:

- energy usage per day (lot or batch basis),
- embedded energy during manufacturing a part (piece basis),
- energy used for value-added and non-value-added activities (between productive operations),
- relationship between spikes/troughs and process parameters (details of process operations),
- impact of process parameters on sub-component loads (what's going on around the machine or line), and
- energy used for machining specific part features (related to part design/geometry and functionality.)

This information depends on vastly differing data rates with sampling times varying from milliseconds to minutes.

The data volumes can be impressive. In the paper we give a sample of the number of energy data values for a "medium sized facility" for a day. This facility is comprised of 25 CNC machines, 10 programmable logic controlled machines and assorted other handling and line equipment. For the CNC machines alone, assuming 8 data sources per machine at a sample rate of 5 hertz (5 times/second), we will have a data stream of 86,400,000 data points each day. If we add the other sources, with reasonable numbers of data collection sites and data rates, we would likely end up with over 100 million data values a day to deal with.

Drinking form a firehouse indeed!

So, what's the solution?

The paper proposes a structure for, first, standardizing data (for example using MTConnect), implementing a modular, scalable architecture that supports multiple concurrent data streams and sources and, importantly, employs multi-dimensional reasoning tools.

There is more to discuss on this but this is more than we can cover in one posting. I'll finish the discussion next time.

If you are interested in this approach in the mean time, Dr. Vijayaraghavan has a company working on the hardware and software aspects of this - System Insights. They are already working with a number of companies and will be demoing some of their solutions at the upcoming IMTS (International Manufacturing Technology Show) in Chicago later this month. (In interest of full disclosure, I am an advisor to System Insights.)

By the way, the IMTS is the "mother of all manufacturing shows" and I plan to attend to check out what the view on green manufacturing is from the show floor.

The next blog will be from Chicago!

Sunday, August 29, 2010

Lead, follow or get run over!


Standards for environmental performance in manufacturing

I was attending a manufacturing conference in Italy this last week and one of the major topics of discussion was green and sustainable manufacturing. There are a lot of other topics to be sure - but this one is building steam. The discussions range from process level issues, similar to the ones we've been discussing, to systems approaches, to design and, at one session, standards.

Not surprisingly, the standards associations (think ISO) have been busy and also, not surprisingly, the Europeans and Asian industry and some academics have been very busy as part of the standards process.

That light you see coming toward you in the tunnel is not the exit!

Let me elaborate.

The standards under development cover environmental and energy efficiency evaluation methods. Specifically, Professor F. Kimura of Hosei University in Japan outlined the work on ISO 20140 "Automation systems and integration – Environmental and energy efficiency evaluation method for manufacturing systems." According to Professor Kimura, who is participating in the standards development process, the environmental evaluation can focus on either a general environmental "intensity" at a rather high level for a facility or be more specific in nature.

I gather that the difference refers to whether or not a generic product being manufactured or system is evaluated. The system evaluation would apply to a comparison of improvements to a system, say by a change in the process or reconfiguration of a machine line or facility. Measurements might include energy per unit production, waste of materials, etc. For the evaluation of benefits or limitations to the production of a specific part or parts in factories located in different countries, there is provision of a general or specific evaluation of environmental intensity of products in manufacturing.

In the language of ISO,  this international standard establishes a method for evaluating environmental influences of manufacturing systems, e.g. energy/resource consumption and pollution.

The standard consists of five parts:
- ISO 20140-1:  Overview and general principles
- ISO 20140-2:  Guidelines for environmental evaluation procedures (this establishes procedures for environmental evaluation and will guide how to use parts 3 to 5)
- ISO 20140-3:  Environmental evaluation index model (this specifies the models for environmental indices, e.g. energy efficiency for manufacturing systems index)
- ISO 20140-4:  Environmental evaluation data model (this specifies data models for the environmental evaluation of manufacturing systems)
- ISO 20140-5:  Facility life cycle impact and indirect impact model (this specifies data models for a facility life cycle's direct and indirect impact on the environment)

To enable this environmental evaluation of manufacturing systems, various types of data from the manufacturing activity will be needed. Standards help to clearly define this data so that it can be used to perform unambiguous environmental evaluations. If there is generally accepted environmental intensity data for unit processes already available, that can also be used in the evaluation.

Much of the data related with manufacturing system definition and operation have been already standardized in related international standards. These existing standards will be included for use and, where necessary, extended.

Professor Kimura described some examples of the categories of likely required data:

- Manufacturing machine/facility (machine tools, conveyers, etc.),
- Tooling and jigs/fixtures,
- Energy,
- Materials,
- Product (definition, quality, function, etc.),
- Process plan,
- Production plan,
- Other production resources,
- Environmental evaluation data (intensity data, impact factors, etc.),

Based on these data, evaluation procedures of environmental index can be clearly defined. According to the definition of data format, it becomes possible for public organizations and machine/facility producers to publish their data. By relying on such published data in  standard formats, reliable and unambiguous environmental evaluation is realized. It also ties in with other existing standards.

For example, there are standards being developed on "Environmental evaluation of machine tools" (ISO/TC 39/WG 12). This is being developed by researchers at ETH (Swiss Federal Institute of Technology) in Zurich. They had a first meeting in May of this year and are working on an ISO series 14955 on this evaluation.

One can find a lot of information about this effort on the web by searching the technical committee (here ISO/TC39/WG12). One link to the Eco Machine Tools stakeholder meeting has several presentations on the elements of this standard.

Professor W. Knapp of ETH is leading this effort. He is a precision manufacturing engineering expert and very familiar with machine tools and their performance. They anticipate four areas of focus for this standard:

- ISO 14955-1, Eco-design methodology for machine tools

- ISO 14955-2, Methods of testing of energy consumption of machine tools and functional modules

- ISO 14955-3, Test pieces/test procedures and parameters for energy consumption on metal cutting machine tools

- ISO 14955-4, Test pieces/test procedures and parameters for energy consumption on metal forming machine tools

The functional modules will allow a certain degree of detail related to energy consumption, for example, the spindle, or drive axes, etc. It was noted that this will only address "use phase" energy - meaning, embedded energy due to raw material extraction, production of the machine or component, transports, set up and end of life energy requirements are ignored. For most of these machines the use phase is dominant.

One of the interesting aspects of these standards activities is the scope. This last standard mentioned will provide guidelines for designing machine tools to meet certain efficiency goals, and then indicate what kinds of parts (shape, complexity, processes needed) to evaluate how well the machine does! The earlier standard will set up a procedure and data requirements for doing comparisons. This will provide a basis of determining whether or not the suggested improvement, or relocation of a facility, will be beneficial environmentally.

One of the illustrations from a presentation made by the ETH folks as part of the TC 39/WG 12 discussion of the standard outlines the system boundaries for the analysis, see figure below. This


defines what inputs and outputs will come into play. Note, in the fine print below the figure, that raw parts in, new tools, etc. and output of machined parts, etc. are not considered if they don't represent a relevant energy flow (figure from Hagemann_Statusreport_ISO found on the stakeholder link above.)

A lot of the motivation for these standards comes out of the CECIMO organization in Europe. They describe themselves on their website as "CECIMO represents the common interests of the European Machine Tool Industries, particularly in relation to authorities and associations. CECIMO promotes the European Machine Tool Industry and its development in the fields of economy, technology and science."

Remember the early discussions about what motivates green manufacturing? I mentioned one was regional organizations - like CECIMO.  The industry is taking the initiative on this.

In the future, we will be designing and building machines and systems to meet these standards. And our factories producing products will be assessed using these standards.

Once again, the "Everett and Jones" philosophy (http://green-manufacturing.blogspot.com/2009/11/stylish-longevity.html) comes into play! Let's not be in the "what happened" category on this one.

I don't intend to. I'm going to follow this one closely and, as "unexciting' as standard development can be, this will be interesting!

We'll keep an eye on the standards activity and I will likely offer more details in the future.

A final point about technology and its impact on energy and the environment.

At another meeting I attended this summer, this one for the Machine Tool Technology Research Foundation (MTTRF) Dr. Masahiko Mori, President of Mori Seiki, gave an interesting presentation on where green product developments will likely impact manufacturing (and, by extension) green manufacturing. He cited some data from Nikkei Monodukuri on the number of parts in an engine for a conventional automobile versus a motor for an electric vehicle - 10,000 to 30,000 vs approximately 100, respectively!

This may seem like a simplistic comparison … but consider the complexity and impact of designing, manufacturing, storing or transporting and assembling 10,000 parts (not to mention the material issues and the building/floorspace requirements) compared to around 100.

This is an example of efficient resource utilization.

Of course there are the other bits needed to make the electric vehicle run - like a battery - but, overall, these are much simpler mechanical devices and will require fewer resources to build and, presumably, be easier to disassemble at end of life to recover the materials.