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 ( 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.

Wednesday, August 18, 2010

That's one way to do it!

Or, how to encourage conservation and save energy

A recent New York Times article discusses the draconian measures being taken by the Chinese government to make the nation more energy efficient ("China Fears Consumer Impact on Global Warming," K. Bradsher, NYT, July 4, 2010). In the last three years China has shut down more than a thousand older coal-fired plants and leads the rest of the world in investment on wind turbines and other clean technology according to the article. In addition, new, stringent, requirements for energy use and auto mileage are in place. But, the concern is that the growing demand of Chinese consumers will overwhelm even these efforts at green house gas (GHG) reduction. Apparently, this last winter and spring showed the largest six-month increase in GHG tonnage ever produced by a single country.

So, swing the ax at the low performers. That's one way to do it.

The NYT articles states that "China’s goal has been to reduce energy consumption per unit of economic output by 20 percent this year compared with 2005, and to reduce emissions of greenhouse gases per unit of economic output by 40 to 45 percent in 2020 compared with 2005."

Recall the "equation" for calculating impact first discussed in the September 1, 2009 posting? It states that:

Impact = Population x (GDP/person) x (Impact/GDP)  where GDP stands for gross domestic production

The challenge in China is that, in addition to population growth with time, the increasing standard of living is driving GDP/capita up and, as was noted in September 2009, unless you can reduce the Impact/GDP (that is, the role of manufacturing, energy generation and resource utilization) sufficiently, you will see the impact necessarily rise.

What is "sufficient"? Well, to close the gap between sustainable use of resources and the business as usual level (the chart that grows "up and to the right" for consumption and impact) you need to accomplish both a reduction in impact/GPP to track the required emissions and consumption trends but also reduce the impact/GDP to offset the growing demand of more and more consumers. It is sort of like trying to pay off a mortgage in an inflationary market when you are constantly taking out equity loans on top of the original mortgage. (Gee, we know how that works out!)

So, what to do? One approach is that used by China.

We are not likely to do that in the US. But, if you do business (or want to do business) in China your products may be affected by these regulations and decisions.

What about in the US? A recent Environmental Leader posting, July 15, 2010, on "Gov Contractors Must Track Emissions or Risk Losing Contracts" adds to the discussion. The article states "Contractors for the federal government that do not track their greenhouse gas (GHG) emissions could risk losing their contracts, according to a report in the Federal Times about new rules by the General Services Administration (GSA)."

It goes on to say that these rules result from the "GSA’s response to an executive order … issued in October which directed federal agencies to find ways to reduce their GHG emissions. Potentially, the new rules could have far-reaching consequences through the entire economy, not just government contractors."

Apparently, "only" scope 1 and 2 emissions reporting would be required, meaning emissions generated by employee commuting and business travel are not included. (We discussed emission scope reporting requirements in a prior posting.)

Given the large role of manufacturing industry serving as government contractors, this could have a big impact.

First, determine what impact your process has (at least energy to GHG conversion) and then roll out the green technology wedges!

So we may need to respond to consumer pressure or, more likely in the short term,  some form of regulation or standardization.

Some may call this taxes of some type. Or at least it has the effect of taxes to many. This is not too popular. I was reminded of Dan Rostenkowski, long time bull of the congress and head of House Ways and Means Committee, who died recently. He headed the committee that wrote most of the tax laws in the UA and he was famously quoted one time as saying "no one calls me up and asks me to raise their taxes!"

Cap and trade, or carbon trading, is often pointed to as one of the "taxes" that will impede industry (while promoting utilization of green technologies for manufacturing.) Another article on Environmental Leader's site calls that into question however. It is not simple. Apparently European Union (EU) companies are offsetting their emissions by improving the competitiveness of their competitors offshore through these carbon credit purchases (!) - so-called "leakage" - moving their business outside the EU. But, it doesn't appear to be increasing outsourcing of business overall according to other reports.

The article gives a neat site by Sandbag that shows a map illustrating the international trade in offsets between the EU and the rest of the world in 2009.

Programs like cap and trade, or regulation, or industry norms adopted to improve the impact of a specific industry all move us towards greener manufacturing. They occur because of competitiveness of countries and regions, real concerns about environment, customer demand, or just plain good economic or business sense.

Apropos that last comment about good business sense, I mentioned in a posting recently the comments of Jeff Immelt of GE on greening industry. He said that "with respect to companies like GE that want to stay ahead of the curve in terms of investing to maintain competitiveness and profitability,  … it’s going to change in like, 15 minutes one day.”  “I guarantee that’s going to happen.” He followed on commenting that since no one can predict when this will happen - you have to plan for this in your business strategy.

Regulation and industry norms take time. Breakthroughs in technology or process improvements can occur instantly. Be ready!

Sunday, August 8, 2010

Degrees of Perfection, Part 4

Last of a 4 part series

We've been talking about exergy (or available energy and useful work) as part of this series. Last posting I reviewed the work of Professor Tim Gutowski of MIT on energy fundamentals in manufacturing. We'll continue along this line for this last in the series with an example from Professor Gutowski's work.

This series has generated some good comments and feedback. One pointed out a mistake in the previous posting (already corrected!) when I used the word "irreversibly" in place of reversibly - the correct word. This was in the quote from Gutowski's paper stating that exergy "represents the maximum amount of work that could be extracted from a system as it is reversibly brought equilibrium …" That is an important catch … sort of like using "nonpotable" for "potable." Thanks to that careful reader. More on some of the other comments below.

Now, on to an example.

Last time we spoke of a "typical" manufacturing system represented by a series of "boxes and arrows" connected serially and representing the individual processes and the connecting material transport between processes. We stated that we can replace (or augment) these arrows between boxes (or going into the box) with the systems mass, energy and entropy interactions. That means that each stage of a process can will have material flows or interactions as well as work and heat interactions. And there will be losses.

An earlier paper by Professor Gutowski used electrical energy in manufacturing from an energy perspective. The paper is titled "Electrical Energy Requirements for Manufacturing Processes and it was published in the Proceedings of the 13th CIRP Life Cycle Engineering Conference in 2006. You can find this publication on the web - it is number 23 under environmental publications.

In the last posting we talked about using exergy as a metric of performance. Gutowski tackles that in this paper.

Gutowski explains as a setup to the analysis that energy measures the potential of all materials to do work. "Fuels naturally have high values of exergy, but many other working materials, including pure metals, plastics and other organics, can have since we can then express these material and energy inputs and outputs in the same unit, usually joules (J).

He goes on. "Secondly, since the development of the concept of exergy is based upon the second law of thermodynamics, and not the first, it is not conserved. Hence this metric provides a measure of what is actually “used up” in the manufacturing process. As a result, a complex energy and material flow problem can be substantially simplified by using exergy analysis."

The process is broken up into two steps:
- 1) identify the system boundaries (that is the limits of the "box" we are analyzing, and
- 2) identify the exergy inputs and outputs.

Then, the difference between the inputs and the outputs is the exergy lost.

The paper explains that this "difference" can be used to "account for material transformations, including the conversion of raw working materials into products, wastes, and emissions, and the conversion of fuels (through combustion) into heat (to do work), wastes, and emissions." One can also extend the concept to incorporate all other energy sources, for example hydro, solar, electrochemical, and others.

Typically, we would consider the conversion of fuel (such as oil, coal or natural gas) to generate electricity which is then used in the manufacturing process for material conversion by, say, machining, grinding, welding, forming, forging, etc. As pointed out in an earlier posting on the variations of impacts depending on differing fuels for energy in different parts of the world, the exact fuel to energy relationship will vary.

The paper reminds us that to be fully consistent, we should take in to consideration the energy used to produce the materials we are "transforming" and, as this blog has argued, include the manufacture of the machinery to do the transforming as well.

The figure below, from Gutowski's paper, illustrates the energy and material inputs and outputs for a manufacturing process. This is a streamlined version of the input-output example discussed on the November 12th posting discussion whether or not lean is green and you can refer to that for additional background on "what's in the box." The example

followed in the paper deals with an automobile production machining line. As we've discussed in earlier postings, the machines used in these manufacturing lines have a number of elements and components that operate in parallel with the actual processing operation. For example, in the paper we are discussing, Gutowski mentions work handling, chip removal and treatment (removing oil) for recycling, tool changes, machine axis and spindle lubrication and temperature control, etc. in addition to actually machining the part. The figure representing this data for a typical automotive manufacturing machining line is below, from Gutowski, and shows the energy use breakdown as a function of vehicles produced.

So, as with our "tare heavy" and production "process heavy" discussion some postings ago) - this is an excellent example of tare heavy manufacturing. Here, a maximum of about 15% of the energy actually goes into machining the part. Granted, this is for a production line so there will be some expenditures of energy that might not be seen with a standalone machine tool. But, this is not very good.

One of the observations of the paper is that there is a variation with production rate. In fact, for standalone machine tools which may actually reach 60% or 70% energy usage for machining (and, thus, 40% or 30% for "all other") this maximum utilization varies with production rate as well. The takeaway is that, in production, there is a significant energy consumption for getting the machine ready for production and maintaining the machine (or line) readiness in the face of fluctuating production.

A more important observation from my perspective is that trying to estimate the energy consumption of manufacturing processes by looking only at the physical process (and the physics behind it - like metal cutting and the energy to form a chip, for example) will tell you almost nothing about the total energy consumption.

So what does this say about our "buy to fly ratio" analysis? To me, this is still a good way to characterize the efficiency of the process. In the example above (and under the assumptions detailed in the paper - the "academic fine print"!) we are utilizing at most 15% of the available energy coming into the process. That is, the transformation part of the manufacturing process is overwhelmed by the peripheral activities and requirements of the machine.

This is precisely what we were speaking about in our "low hanging fruit" discussion referenced above and what is motivating a lot of current development work by builders of and users of manufacturing machinery.

More on this to come.

Finally, one of the more prolific commenters to the blog talked about standardizing "by volume the process by which inputs, energy included, are transformed into outputs." A visual thinker! She goes on to say that with this approach "the perfect shape would be a cylinder, where all the outputs are useful, for nature, for humans or for both. The current processes are truncated cones with different "buy-to-fly" ratios symbolized by the ratio between the two bases. The cylinder's ratio is the perfect 1, no volume is lost."

The thought that came to mind when I read this was Rick Steves packing for a long trip on one of his adventures. He always seems to be wearing the same shirt and carries only a small backpack. How does he do that? If true, his "buy to fly" ratio must be close to cylindrical! That's perfection.

And, in the world of twitter - I learned of one called “50 Best Twitter Feeds To Stay On Top Of Green News”. The writer thought some of the blog readers might find it interesting. So, happy twittering!