The current issue of Business Week has a three-page rave on bioplastics: “I Have Just One Word for You: Bioplastics”. The deck on the story starts: “The scourge of indestructible garbage and sky-high oil are fueling interest in plastics from plants.” It turns out the story is really just a tout for startup company: Metabolix, which is developing a form of genetically engineered polymer that grows within plants. Very cool idea indeed. The rest of the bioplastics industry is largely dismissed by BW with the comment “rival bioplastics must be incinerated or composted at high temperatures.” The Metabolix plastic, trademarked Mirel, will decompose if it is simply tossed in a home compost heap or dumped at sea”. Wow, here we go again. To make this work, we have to dump our plastic waste in a compost heap in our backyard. Sure, some folks will try it – until their dog rolls in it or odors start to waft in the window on a hot summer night. In my view, that’s a pretty flimsy basis on which to start a new industry.
There are other issues:
- Mirel will be produced in a new factory that uses corn as a feedstock. Microbes eat glucose in corn and convert the sugar to a polymer. Corn supplies are already strained by world food demands and ethanol. The BW story shows the inventor of Mirel with switchgrass and oilseed, revealing the promotional nature of the article. As noted here, the future of bioplastics will not be in food crop feedstocks.
- The new polymer will be priced at $2 a pound, more than double the currently inflated price for the commodity plastics used in packaging. When the oil bubble bursts, as it always has, commodity plastics prices will tumble once again, while corn is unlikely to drop significantly.
- There’s no mention in the article of how much energy it takes to produce Mirel – a major issue with ethanol-from-corn production.
There are some bright spots:
- Maybe Mirel can be made some day from switchgrass and oilseed.
- It seems to make a lot of sense for waste dumped at sea, and the U.S. military is studying use of the material as a liner that is thrown overboard.
I’m all for developing technology that solves the plastics’ hydrocarbon and solid waste issues. But we have seen too many hollow marketing promises with biodegradable plastics and not enough real technology. I applaud Metabolix, but really wish Business Week had put a little more effort into their report. .
If you’re truly concerned about climate change, do something meaningful: Turn off your air conditioning. Car pool. Support solar power.