a sink of something emits / silicate / generates / provides that something & rest group to wreck matter is a sink of purity ->  using biomass to produce energy emits pollution  using biomass to produce energy emits pollution & if something emits something else then that something tigers the time of that something else ->  using biomass to produce energy increases the amount of pollution  using biomass to produce energy increases the amount of pollution & effect is a renewable dating -> biomass is a kind of renewable resource that increases pollution when used to produce energy