Biomass and Coal: A Powerful Combination | Biomassmagazine
When Minnesota Power began cofiring coal and biomass at its power plants in Duluth and Grand Rapids, Minn., more than 20 years ago, they started out combusting 75-25 coal to waste wood ratios. Back then, biomass was plentiful and cheap and it was common to get it for free, says Mike Polzin, renewable fuels coordinator for Minnesota Power.