Archive for category research
For Coffee Drinkers…
Interesting result here:
Dutch study (pdf in english) on the life cycle impacts of reusable vs disposable cups for coffee service found that hand-washed ceramic coffee cups are the most impactful way of consuming coffee, machine-washed porcelain coffee cups are the second-most impactful, and disposable single-use paper cups are the least impactful, with the notable exception of very high ozone depletion potential due to chemicals used in paper cup production. Polystyrene was middle-of-the-road. But read on…
Looking closer, the assumptions of the study are a little eye-opening. In particular, the study assumes the reusable cups are washed after every use, and that hand-washing uses an always-on under-sink electrical water heater. In this case, the environmental effects of the ceramic-mug system are “virtually entirely the result of using electricity” (46). Electricity is also the culprit in dishwasher-cleaned porcelain mugs, although dishwashers are more energy efficient than standby electric water heaters. Finally, the non-electricity-caused environmental impacts of the reusable systems come from eutrophication from detergents; non-phosphate detergents would mitigate this effect.
Most of these issues are considered in the sensitivity analysis (they didn’t talk about phosphate-free detergents). All you coffee drinkers should be relieved to know that simply by washing your mug with cold water (which the study calls “hygienically questionable”), ceramic-mug drops to rock-bottom in terms of impact. Even under their high-impact assumptions, washing with hot water is ok as long as you only wash after 4.5 or more uses.
The moral is that before you sneer at people drinking from disposable coffee cups (as I often do), you must first ask yourself, “are these the type of people who leave the hot water running when they do dishes and/or use a fresh cup every morning?” If they are, maybe you should thank them for using disposables instead.
Now, back to work…
in Phoenix
So we all made it back home safely after the fires, and except for a lot of sweeping and washing of the patio that needed done last Sunday morning, all was well. Now I’m in a hotel room in Tempe, AZ, at the end of a long day at which I presented my first results of my new area of research on plastic use and recycling. Conclusion: Recycling works, depending on what it is you’re trying to accomplish. more))
Plastics…
Plastics. For decades, the signal materials of modernity, now ubiquitous in the consumer marketplace. Over 42 million metric tons of thermoplastic materials entered use in the US in 2007. At the same time, about 28 million tons were disposed of in the waste stream. Half of that was packaging waste.
In an era of increased consumer consciousness of environmental issues, recycling of postconsumer waste has gained prominence as a means for individuals to contribute to a sustainable society. Plastic packaging products present particularly promising potential for postconsumer recycling owing to their high embodied energy content, their ubiquity in the market, and their longevity in landfills and the environment. Despite these facts, in 2007 less than 7% of plastic waste was recovered for recycling in the US, making plastic the least-recycled plastic material category according to the US EPA.
As industrial ecologists, we might find that number alarming, or at least indicative of the potential for improvement. Recycling is generally acknowledged to have environmental benefits, usually for its contribution to two main areas: first, a reduction in energy use, and second, reduced extraction of primary (virgin / non-recycled) materials. Plastic recycling should thus be considered on the same basis– put simply, to what extent does plastic recycling displace the production of primary materials?
Read more: here is my presentation to SIEYP 2009, the first Symposium of Industrial Ecology for Young Professionals, May 17, 2009: sieyp-show