The city of Akron, Ohio, is joining forces with KG Compost Services and Germany-based Schmack Biogas AG to construct a $7 million plant that will use bacteria to convert solid waste into electricity. The process, still in its infancy in the United States but booming in Europe since the mid-1990s, uses bacteria that do not require oxygen to digest the waste and produce gas, which then powers the electric generators. City officials say that the multiplying bacteria will help reduce the $1.3 million the city spends annually on electricity costs for sewage treatment, estimating that the new operation will use 20 to 30 percent of the energy it generates. Remaining gas may be used to fuel other sewage treatment operations.