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, February 25, 2010

Scratching the Surface


In one of the recent past blogs I was talking about "low hanging fruit." This came about in response to a discussion about things that companies do to address the concerns of 1) understanding what green manufacturing means to them, 2) understanding how to make some measurement of "green-ness", and 3) using that, determine where they are on a scale of "green-ness" using those metrics.

A comment came in to the effect that "this is great for large companies, but what can smaller companies do if resources (financial or staff) are limited?" So ... I said go for the "low hanging fruit" and proceeded to give some examples. I received a number of comments about that discussion and a subsequent one on "choices" that you are confronted with when, with these metrics, things don't always fall clearly on one side or the other of the green line.

I am accumulating more examples, and some more straightforward analysis ideas, of low hanging fruit and decision making and we'll get back to that sometime in the future.

So, how are the title of this posting and low hanging fruit connected? Simple - the low hanging fruit is not always the most effective way to address the problem in the long run. You may have to dig a little deeper. That is not to say that we should "leave any energy on the table" but it is necessary to understand the magnitude of the challenge and where to best concentrate your efforts. And, sometimes the easiest stuff doesn't do much to advance the cause, specially with respect to greening manufacturing.

I like to represent "sustainability" as in the diagram below - referred to as a sustainability frame of reference. The diagram shows, along the vertical axis, a level of impact (like generation of green house gases) or consumption (like energy, water, other materials) as a function of time along the horizontal axis. Usually, unfortunately, these curves of consumption and impact, go from lower left to upper right



indicating increases over time. This is usual because there are more people and, even if they consume the same or impact the same per capita, more people means more impact or consumption. Then, we can usually define a sustainable rate of impact or consumption. Scientists and others are discussing what is a sustainable rate of green house gas emission (GHG)in order to maintain a certain max level of CO2 in the atmosphere. We can, for example, define a sustainable rate of water consumption based on rainfall and underground sources so that we don't deplete the natural sources by overuse. Unless we can get to that level (use without depleting the resource for the future ... that's future as in "forever") we will not have a sustainable situation.

The problem is that we are usually over the sustainable rate of consumption or impact. So the challenge is, to each of us in our own area of influence, to reduce this so that over time we reach sustainability. The gap shown between the growing curve and the sustainable level is impressive and growing. We are not likely to close it with one solution. This is where the concept of "technology wedges" comes in. I refer to opportunities for greening  after a concept proposed by Pacala and Socolow to address the big gap between the present trajectory and impact of CO2 on the atmosphere (business as usual – BAU) and a sustainable level – and how to close this gap in 50 years. (The full citation is “Stabilization Wedges: Solving the Climate Problem for the Next 50  Years with Current Technologies,” Science 13 August 2004: Vol. 305. no. 5686, pp. 968 – 972.)

The technologies for greening manufacturing are each "wedges" that, when added together, can make a significant impact (along with all the other wedges from other sources). These wedges will include some low hanging fruit but will, probably, require many significant changes.

To determine how significant, we need to look at some information. Let's turn to some high priced consultants! For example, McKinsey published volume 2 of its "Pathway to a Low Carbon Economy" Report in 2009 (see http://www.mckinsey.com/clientservice/ccsi/pathways_low_carbon_economy.asp to download your own copy) to, as it states, "provide an objective and uniform set of data that can serve as a starting point for corporate leaders, academics, and policy makers when discussing how best to achieve emission reductions." The report does not deal with assessment of regulatory issues or policy effectiveness.

The McKinsey report focuses on the goal of reducing green house gases enough through the year 2030 to keep global warming below 2 degrees Celsius. The results of their analysis indicates (and I quote from the report here):
- Opportunities can be grouped into three categories of technical measures: energy efficiency, low–carbon energy supply, and terrestrial carbon.
- Capturing all the potential will be a major challenge: it will require change on a massive scale, strong global cross-sectoral action and commitment, and a strong policy framework.
- While the costs and investments seem manageable at a global level, they are likely to be challenging for individual sectors. And,
- Delays in action of even 10 years would mean missing the 2 degrees Celsius target.

OK. So let's not get into whether or not we all agree that global warming is significant, but, this is one of the "gaps" we discussed above and the report puts some scale on the "size of the wedges" needed.

So, what can we do? What are the wedges we could employ here? Here is a neat representation of the "cost of abatement" to achieve these reduced levels of atmospheric CO2 from Vattenfall (a European energy company) done as part of the McKinsey study. You can get the report this is from http://www.vattenfall.com/en/file/2-20091123-11091566.pdf. The chart shows (and you'll probably need to click on the image to get a larger version to see the details) the cost of abatement (or reduction) of



CO2 based on a series of "wedge technologies" or opportunities to reduce GHG emissions.  The height of each bar represents the global average cost in Euros of avoiding 1 ton of CO2 equivalent for each measure. Negative cost means the savings realized in the improvement pay for the technology employed or change made for the improvement. The graph displays, left to right, the lowest-cost abatement opportunities to the highest-cost. From left, we see improvements in insulation, fuel efficiency, lighting, air conditioning, etc. all the way up to "breakeven" at standby losses. Actions further to the right (with a positive cost shown, in euros/ton of CO2 equivalent abated) will not break even. You could call some of the far left ones (no political connotation implied!) as low hanging fruit but many, such as improved fuel efficiency will not come easily.

Many of these technology wedges are related to manufacturing. Fuel efficient vehicles require precision manufacturing to make more efficient engines, drive trains, etc. More efficient air conditioning systems need to be manufactured. And we want to make sure that the "environmental cost" of that manufacturing figures into our decision on what technology gets the efficiency more efficiently. Reduction of waste requires changes in manufacturing throughout the entire supply chain. And so on for most of the items seen in the figures.

Next time we will look at what is really needed, more than a scratch, to change the impacts from manufacturing to turn the curve around and approach sustainability. We will go into in more detail on the level of change needed. More than just low handing fruit or scratching the surface.

Friday, February 19, 2010

Motivations for Green Manufacturing


Or ... the ball is rolling

In an early blog posting (July 20th to be exact; http://green-manufacturing.blogspot.com/2009/07/why-green-manufacturing-part-1.html) I started out by posing the question "Why green manufacturing?" This was in my input to what appeared to me to be a lot of discussion and confusion about terms, motivations, likely results and procedures in greening manufacturing.

The justification I gave was as answers in response to the question "why does industry care?:

- Pressure from Government (and let's think global...EU, Asia, US, South America, the whole world's governments - yes, even the UN) in terms of regulations, penalties, tax benefits or obligations. The EU has been very proactive here; US is working on it; China, for example, is working hard on new regulations for both domestic industry and imports.
- Interest in Efficiency/Reduced CoO (remember Deming?) His principles apply here. Waste is waste; reduced cost of ownership (CoO) is still the mantra in most industries (check out semiconductor industry where this is the motivator). Time is money...energy is money...consumables are money. If you can make the same product using fewer resources/energy that seems like a good strategy.
- Scarcity of resources/risk; if you need water for your product and, suddenly, you can't get it in the quantities you need for manufacturing...this is a problem! This is not an abstract concern. Green manufacturing applies to resource availability as well as energy and emissions.
- Continuous Improvement (back to Deming!); while we are working to improve our systems and processes let's integrate green practices as well.
- Pressure from Society/Consumers/Customers; Not to mention your kids! Your customers may not be able to define it, but if you can't show a serious effort in green manufacturing they may go to someone who does; and it may be for a variety of reasons...but why take that chance.
- Pressure from Competitors; if they can do it, and win market share and be profitable as part of an integrated strategy in their business - shouldn't you? Let's not repeat the mistakes of past industries who felt they were isolated from (or simply misread) the shifting market.

When I posted this, last July, I began accumulating evidence in support (or opposition) to these assumptions. One of my favorite web sites, Environmental Leader (see link at the bottom of this blog page), has a number of examples, opinion pieces and news notes that support these motives for green.

On February 8th, Maria Cramer has an article there on how to use what you have to grow sustainability in your organization (see http://www.environmentalleader.com/2010/02/08/accidental-to-purposeful-sustainability-using-what-you-already-have-to-grow-sustainability/). In the article she mentions the following benefits:

"Respect for environment – Your business is doing its part to better the community" and  "Respect for the bottom line – Your business will save money by reducing the use of such things as consumables and natural resources."

Pretty close to the society pressure and efficiency/reduced CoO of my list (and recall CoO is "cost of ownership" - the full cost of purchasing, installing, running, maintaining, and disposing of a piece of equipment, or system, factory, etc.)

Another advert announces a meeting of the Alliance for Water Stewardship roundtable on "Understanding, Measuring and Managing Water Risks, Footprints and Impacts Throughout your Supply Chain" this coming April in London (http://www.corporate-water-scarcity-risk-management.com/). That's item 3 on the list above.

Another one of my favorite "go to" sites is Greenbiz.com (also with a link below). They just published their "State of Green Business 2010" Report (see http://www.stateofgreenbusiness.com/). It is a long and comprehensive report (but free and can be downloaded - green indeed!) but mentions, among other items, that green innovation has become seen as a great idea - and points out that

"The emerging green economy is about much more than green products and services. Behind them are countless materials, processes and technologies. And as the parade of progress marches inexorably forward, a growing number of innovations have a distinctly green tinge, significantly reducing material, chemical, water and energy inputs. Some of the innovations enable closed-loop or cradle-to-cradle products or processes, with little or no problematic waste or emissions." (Source: State of Green Business 2010, Greenbiz.com, page 8).

Wow - we couldn't agree more! And we hope this blog helps to keep up the momentum. This is continuous improvement and efficiency/reduced CoO.

By the way ... just so we are all clear, I am not suggesting all these people read the July 20th blog and then took action! I'm just trying to add evidence to the motivations proposed.

Finally, as a mechanical engineer I naturally am a member of ASME (American Society of Mechanical Engineers) and get their monthly magazine "Mechanical Engineering" (appropriately titled!). This month there is an article on "Compelled to be Green" by Jeff Winters that reports on an ASME/Autodesk study on sustainability (called the Sustainable Design Trend Watch Survey) to determine the interest and attitudes of ASME members on this topic.

The article made a few summary statements about the results. For example:

"In spite of the recession, most working engineers reported that their companies continued to be involved with sustainability or sustainable technologies. Indeed, more than 24 percent reported that their companies were extremely involved in sustainability and 43 percent were somewhat involved.

Of the 89 percent who said their companies had any level of involvement, just over seven in ten reported that their companies were creating designs that use less energy or produce fewer emissions. More than 70 percent also responded that their companies were producing designs specifically to comply with governmental standards and regulations.

About four in ten reported that the companies they worked for were involved in making designs that use non-toxic materials, or recycled materials, or a reduced amount of material in manufacturing."  (Source: Mechanical Engineering, February 2010, page 42; and see http://memagazine.asme.org/Articles/2010/february/Compelled_Green.cfm for the full article.)

That seems to be pretty good support for the continuous improvement argument along with the pressure from government regulation motivation.

And all of these examples lend credence to our interest in developing tools for analysis and execution of designs and manufacturing to insure that the greening being considered is going to be as impactful as we hope.

Much more to come on this.

Next time we'll talk about what level of change will be needed to truly affect greening and a significant impact on global warming and  resource use. Brace yourself - low hanging fruit is not going to do it.

Thursday, February 11, 2010

Pro Choice for Green


Or ... go climb a hill!

I hesitate to use such a provocative title but, relative to the posting last week, I believe it is the only way to go. I'll get to why in a bit.

Recall that last week we discussed the problem of reducing the complexities of determining whether one process was "more green" (or less impactful) than another. And I referred to this as the "paper or plastic" question.  I said that the phrase "paper or plastic" points out the often confusing choices we are faced with when trying to do the right thing. I then gave a great example of this from a Brazilian colleague who was comparing grinding versus machining in a manufacturing example.

So, relative to those kinds of decisions - I am definitely "pro choice". Let me explain.

Depending how large you draw the control volume (meaning, how much of reality you want to include in your analysis) you can get some different pictures of the impact of a process (or product) compared to another. This was the basis of the paper vs plastic dilemma. Some say that, because the plastic bag weighs a lot less than a paper bag (and since transportation is often the biggest contributor to the impact of plastic bags) you can transport many many more plastic bags for the same volume of paper bags. So, on a "per use basis" (and there are other considerations of course but let's keep it simple for the moment) the plastic bag has less impact. Of course, others cite issues with recycling (paper is usually easier) or litter (you rarely see paper bags flapping in the breeze on fences along the freeway) as considerations that tip the balance towards paper. And then there are reusable bags (paper or plastic). People can honestly choose one over the other and argue, with some scientific evidence on their side, that their choice is "best." But, this always depends on the control volume. How wide are you willing to cast your net to include all the important bits of data in impact? But you have to make a choice.

I often use a simple example with students (told to me in a seminar a decade ago by an early environmental engineer for a major consumer product company). He posed the question: which is better - to make your orange juice from a frozen concentrate (or at least liquid container) or to squeeze locally purchased oranges yourself to get the juice? Berkeley students almost always went for the "squeeze it yourself" option since is sounds more green. Of course that is not correct (unless you have an orange tree in your backyard that is). Since transportation is the major source of "orange juice environmental impact", the density of shipping concentrate or liquid OJ is so much greater than the juice content in the orange as shipped - there is no comparison. Of course, we don't consider taste here.

The important point is that you have to carefully consider the key information when making the decision - information like:

- how much of the process chain (or supply chain) do you want to include?
- how much of the intangibles should be included (meaning, as in the OJ case, taste or more generally the non-quantitative aspects of the decision making like litter in the paper or plastic case)?
- how do you want to value the future (meaning what is your time horizon and do you need to worry about - the next 10 years, 100 years, 1000 years)?
- what do you do about data you don't have or can't get hold of easily (meaning, for example for many materials, the data sheets are non-existent or very sparsely populated, or the business practice of that small supplier to you in some distant part of the world is not apparent)?
- how sure am I that the information I am using today is going to be valid tomorrow (or the next quarter, or fiscal year; meaning prices change, vendor practices change, markets change, etc.)?
- how do I know what the state, federal, international regulations are going to be in the future?

And so on.

Fortunately, the situation is not insolvable. I am an engineer. Engineers have been confronting these types of "uncertainties" for centuries. Mostly we made great progress with few mistakes. Sometimes we made really big mistakes (see Tacoma Narrows Bridge, Challenger Space shuttle, New Coke - well ... let's not burden engineers with this one!) but we always learned from these and made progress. Same situation for the "paper or plastic" question.

We can make a choice, and feel comfortable with it, if we have done our due diligence in attempting to understand a reasonable range of the process or supply chain we have the most influence over (and that we believe captures the most of the impact) and use our best judgement to fill in the pieces we don't know well or at all or can't find information on. This gives us a start. We can go through the other information uncertainties listed above in the same way.

If we feel we are on really thin ice then we need to update our analysis or decision frequently to see if better information is available. We need to keep asking questions and "fill in the blanks" as we gain experience with our system. It's sort of like one of these Sudoku puzzles ... but sometimes with only a few numbers filled in to start with.

When I was a graduate student I took a course on a statistical methodology called "response surface methodology" or RSM. This was intuitively very easy to understand. Relative to the problem we were solving, it assumed that the world could be represented as a hill. The optimum place to be was on top of the hill. We were not able to see the whole hill but could, from our present position, reach out in four directions and try to "feel the slope." You did that by running some experiments over a range of conditions, or some simulations, or other testing (think Taguchi). Then, based on the results of that, plan a next move in the direction of steepest ascent. By repeating this we eventually climbed to the top. (And don't ask what happens if the "hill" is just a small bump on the side of the real hill - that, of course, complicates things).

Decision making in green manufacturing is a bit like that. We make our decision (or our choice of paper vs plastic, frozen or squeezed, and so on) based on where we think we are on the hill and how we feel the slope of our situation. We need to collect enough information to get a reasonable feel for where we are and what is the likely direction to climb the hill. If we can do that, we can feel comfortable that we are making progress.

In some of the previous postings I've reviewed ways to "feel the slope of our situation". These can be helpful in our decision making. Not making a decision is, after all, " a decision"!

We all have to choose to either stay with what we have or look at alternatives that can offer green solutions to our processes and systems. And in choosing those alternatives we need to go with what we can discern and where we feel the slope is steepest.

So, make your choice and happy climbing!

Thursday, February 4, 2010

Paper or plastic?


We aren't really going to delve into this question at this time (although in the LMAS we are working on sustainable packaging and how to add some clearer data on benefits/costs/tradeoffs in packaging choices - more on this in a later posting) but it is phrase that we are confronted by more often these days. I've seen hard core environmentalists stumble when asked this in the grocery store line. The truth is, not surprisingly, the answer is not simple. Depending on what you consider in your analysis, the answer may be different.

The phrase "paper or plastic" does point out, however, the often confusing choices we are faced with when trying to do the right thing.  We'll talk about this in this posting (and have a bit more casual conversation than the past few blogs.) The topic is really comparisons between comparable technologies and how they stack up in terms of green manufacturing.

At a recent conference in Europe on manufacturing engineering there was a growing presence of green and sustainable topics of discussion - ranging from the folks like myself who are looking a systematic ways to address, assess and act on green technology for manufacturing to others who are simply trying to figure out what is best. That is, paper or plastic?

A good friend and colleague from Brazil and a grinding expert, Dr. Joao Oliveira, gave an interesting paper on "Sustainability performance assessment of Grinding and Turning applications." Meaning, in a face off between grinding and turning - which is more "sustainable?" Logical question, right?

For those of you who are not manufacturing processing folks, grinding uses abrasives fixed on a wheel or other shape, rotated against a workpiece to remove small amounts of the workpiece with each engagement of the abrasive grain (the piece of abrasive) with the work. It is able to remove a lot of material of different types and create a very nice surface finish. So, many components in your automobile (like crank shaft, valves, etc.) or in jet engines are ground. Turning uses a single point tool made of a hard wear resistant material to remove metal in chips by engaging the workpiece (which in this case is turning, or rotating, hence the name) along the length of the material to be removed. Usually this has a higher material removal rate and can handle some more complex shapes but doesn't yield a fine a surface finish.

Both processes can use liquid for chip handling and temperature control, or not. Both require energy to drive the process and both are widely used in industry.

My friend Joao reviewed what the industry and researchers normally consider as the basis for  assessment of grinding vs turning:
- minimum setup time
- process flexibility
- material removal rate
- low residual stress
- process reliability
- quality of surface roughness
- dimension and shape accuracy
- low sub-surface damage, and
- environmental compatability

These are all production characteristics that are important to manufacturing productivity as well as quality. Things like residual stress (the tendency for a part to deform after processing due to an imbalance in the stress state from machining - like distortion or warping) and subsurface damage (excessive destruction of the basic material condition below the surface, and not visible, that can limit the life of the product in fatigue situations) as well as the others need to be controlled in any fair comparison or else the processes are not interchangeable.

It is important to note that one cannot generally simply replace grinding with turning (or the reverse) but there are many situations where they can be interchangeably used. For a fair analysis one needs to try to start with those situations.

Now, on to the "comparison." Dr. Oliveira put forward a set of "core sustainability performance aspects" that could be used as a basis of evaluation of these two process choices (assuming the results of the processes, according to the items above, are as close to the same as possible.) The figure below, from Dr. Oliveira, summarizes these aspects.


As you see, these aspects address the three pillars of sustainability- finances, environment, and social.

It is interesting to see the elements chosen for evaluating the sustainability of the processes. Certainly, cost is one piece. But we also see ROI considerations, energy, emissions/waste and effluents, labor relations, training, health and safety, and so on.

Some of these are easier to characterize than others. Labor relations was measured by average salaries of machine operators for the two cases. Health and safety was measured by job related accident data, noise levels and risk data. Apprentice training data was used to assess training differences as a social element. ROI info can come from investment calculations for comparable (in capability) machine tool costs of purchase, maintenance and disposal. End-of-life information was based on retrofit costs to return a used machine to productive use (a typical end use scenario for machine tools).

The study then used three "business" scenarios as a basis for decision making (The question to be answered was - Which of the sustainability dimensions is more relevant in this scenario?) :

Scenario 1: Economic return and environmental laws and standards followed
Scenario 2: Cleaner production strategy
Scenario 3: Sustainable production strategy

It is hard to give all the details of the analysis ... but, to summarize:

- When the environmental and social dimensions grow in relevance, turning has the larger advantage. This is likely influenced by the energy/unit of material processed, the size and nature of the "swarf" (or chips) which, for grinding, are very fine and often considered to be more hazardous, and, grinding has a potential for more severe accidents due to wheel problems, etc.

- The economic performance of grinding appears to be superior than turning, probably due to the cost/performance in which grinding gives a better surface quality, for example.

- With respect to health and safety, turning shows better performance considering health and worker safety indicators while grinding is superior with respect to salary and training.

- Overall, there was no real difference with respect to the two from a purely "social dimension" but one would conclude that turning was more "sustainable."

Dr. Oliveira was quick to point out that this is not the death knell for grinding! But, it is an interesting example of a sober comparison. And Oliveira's presentation was followed by one from a US company heavily into grinding, specially for very large components as in wind turbines, who showed that, in terms of specific energy (energy per volume of material used), grinding was way ahead!

So ... there you have it. As I stated in the beginning, depending on what you consider in your analysis, the answer may be different! This is not surprising, nor is it a problem. What is encouraging is that one can consider this wide range of elements around a process choice and get answers that are reasonable.

Finally, in the "odds and ends" department, I served as a judge for a recent business plan competition on the Berkeley campus. If you are not familiar with these, some organization or company pledges a reasonable sum of money to the team that has the best business plan for some new product, system, etc. Smart students flock to these like moths to a light.  In this case it was for socially relevant business propositions.

One of the teams represented a new venture in the bay area, BTTR (or Back to the Roots) which was, to me, as clear an example of a sustainable business as you can find (and see  http://www.bttrventures.com/ for more details.)

From their website they state that "BTTR Ventures, formed by two 2009 grads from  UC Berkeley, is turning one of the largest waste streams in America, the tons of coffee ground waste generated daily, into a highly-demanded, nutritious, and valuable food product – gourmet mushrooms. Currently, BTTR Ventures is transforming over 6000 lbs a week of coffee grounds from Peet’s Coffee and Tea into delicious oyster mushrooms, the BTTR Garden (grow-it-at-home mushroom kit), and rich compost (spent mushroom substrate)." So, diverting tons of waste from landfills, taking waste off the hands of companies that otherwise need to pay to get rid of it, growing, locally, a valuable product (specially in the gourmet bay area) - all positive steps.

And, I learned that at the end of the growing cycle, the rich compost can be used for soil to plant more crops ...  maybe even grow coffee! Talk about cradle to cradle.

I know, some of you are saying ... mushrooms?! But, examples of successes are important. Mushrooms today ... machine tools tomorrow!