Environmental laws often have unintended consequences. The Michigan Legislature passed a bill that became law in 1995, requiring landfills to compost yard waste. Elected officials decided this was necessary to preserve landfill space - even though Michigan has plenty of landfill capacity for the foreseeable future. Composting produces dirt with high organic content, which is popular for gardens and landscaping (however more dirt is being produced than can be sold, resulting in the material being stockpiled at many landfills). Another problem is producing dirt comes at the expense of producing clean alternative energy.
Landfills produce gas composed of approximately 50 percent methane (primarily natural gas) and 50 percent carbon dioxide. Landfill operators have two alternatives in dealing with the methane: flare it off, which releases greenhouse gases (methane is 23 times more potent as a greenhouse gas than CO2); or capture the gas and sell it to utilities as renewable energy. Unless the yard waste ban is lifted it will become increasingly difficult for landfills to economically produce alternative energy. The high organic content of yard waste is important in boosting energy production from landfills.
According to a report prepared by Public Sector Consultants for the Granger Company, there are 20 operating and 12 potential landfill gas-to-energy facilities in the state. The study estimates that adding yard waste to these landfills would increase alternative energy production by 41 percent; up to 265.6 MW by 2015 - enough to heat approximately 200,000 homes.
Two bills have been introduced in the legislature - HB 5334 and SB 725. Both allow the placing of yard waste in landfills as long as the requirement of producing at least 70 percent gas from landfill waste is met.
As with almost all public policy there are tradeoffs. However trading dirt for alternative energy is a no-brainer. Landfill-produced methane is a 24/7 energy resource, which is not the case for wind and solar energy. Landfills should have the option of utilizing yard waste to produce alternative energy instead of dirt. The Legislature has an opportunity to get it right this time.