Wednesday, September 9, 2009
Defining Manufacturing Lifecycle
We have been talking a lot about manufacturing (and related terms such as green, sustainable, low-carbon, clean-manufacturing) but it seems like we should spend a little time making sure everyone is on the same page with respect to what I mean when I say “manufacturing.”
Environmental Leader (see link at bottom of page) periodically "re-posts" some of my older blogs on their site. A recent re-posting covered a discussion I had about the differences in the CO2 impact of the embedded energy in manufacturing an automobile and how the location at which you produce a product can make a big difference (originally posted here on July 23rd). The blog then went on to discuss other aspects of manufacturing that need to be counted - including transportation. In response, a reader commented that there should be more attention paid to transportation (distance, mode and energy impact) in determining where something should be paid.
I agree fully and I've mentioned aspects of this before. But, this reminded me that we should define more specifically what we mean by manufacturing so that when we discuss impacts we are sure to include all the important stages and elements. So, that's our topic for today.
When I first started teaching manufacturing courses (back in the last century – I’ve been waiting for a chance to use that!), manufacturing was defined primarily as metal working using machine tools and conversion of materials by conventional processes (cutting, forming/forging, welding, etc.). Of course, that was a narrow definition then (it excluded most electronics - 30 years ago they did not play the role they do in our lives today; the topic probably touched on plastics a bit). That definition certainly is way too narrow now. So, thinking of all the products manufactured today (just look around your office or home for starters), how do we define manufacturing?
If you Google manufacturing you'll come up with a Wikipedia definition that works pretty well (I don't normally recommend this as a primary source to students but for this discussion it is fine - see http://en.wikipedia.org/wiki/Manufacturing):
"Manufacturing is the use of machines, tools and labor to make things for use or sale. The term may refer to a range of human activity, from handicraft to high tech, but is most commonly applied to industrial production, in which raw materials are transformed into finished goods on a large scale. Such finished goods may be used for manufacturing other, more complex products, such as household appliances or automobiles, or sold to wholesalers, who in turn sell them to retailers, who then sell them to end users - the 'consumers'."
This is usually restricted to “discrete parts manufacturing” (i.e. not refineries). The only part they miss in this definition is what happens after the consumer is done with the good, or the good is obsolete or worn out, and it is disposed of, recycled, re-manufactured/re-used, or discarded. That must be included since, more and more, it plays an important part in the manufacturing process and the company responsible for manufacturing the good may be required to take it back when the consumer is finished with it. We'll discuss this more in the future but check out some of the EU regulations, for example waste electrical and electronic equipment (WEEE) requirements.
A full picture of the product "life cycle" starts at the source of materials (mine, well, forest, ocean) and extends through conversion to processing to shipping to distribution to use to reuse/recycling - the whole nine yards. Think of a “simple” product like an aluminum beverage can. First, ore is mined, then converted to raw metal and formed into billets or plates and then sheets, then manufactured by deep drawing into cans, lids and pull tops and labeled, filled and packaged, transported to distributors, then to stores/outlets and customers, used and finally, recycled (back into the material flow).
A cartoon of the full life cycle is shown in the figure above (you may have to expand this to get a clear view) and what is labeled as the “manufacturing” part is actually only a small part of all the processing, handling, transformation with accompanying energy, resources (materials and consumables) and environmental impact. So, to be correct, we really need to see manufacturing as including all these elements – except maybe the use phase (unless the product is a machine tool and you are a manufacturer using machine tools in your production!). Thus, transportation is a critical part of the resource use and impact analysis. But, so is “pre-processing” of materials used in the circled part. If you use a material which has been extensively processed before entering your facility (so you don’t need to) then you also need to count for the embedded energy, resources, and impacts of that pre-processing. From “cradle to grave” (or “cradle to cradle” as McDonough and Braungart suggest – see http://www.mcdonough.com/cradle_to_cradle.htm) the manufacturer must consider all the impacts. Else, when folks in other parts of the world start regulating embedded energy or cumulative impacts along the supply chain, you’ll be surprised at what’s in your product that you are accountable for!
There are a number of ways to account for all this embedded energy and resources and we’ll be speaking about them in the future. We are already doing simple tradeoff analyses for transportation and manufacturing. A recent study on supply chain optimization and planning for solar panel manufacturing shows the impact of efficient and inefficient means of transport as well as energy mix at different manufacturing locations showed that the energy payback time (time it takes to generate enough energy to offset manufacturing use) of solar panels can vary from 0.6 to 5 years depending on manufacturing locations (download the full paper at http://repositories.cdlib.org/lma/gmg/reich-weiser_08_5/).
If you look, and can measure and evaluate, you find opportunities!
We’ll be diving a bit deeper into manufacturing, and the opportunities for improving the footprint of manufacturing in the next posting.