In some cases, utility incentives help pay for some part of these backup generators when they can be brought on line to help reduce the utility's peak load. Many are being installed now primarily by smaller consumer-owned utilities to meet local peak load demands. If grid power is available, the high operating costs of engine-driven generators relegates their use for peak shaving and emergency conditions. Biodiesel fuel is a blend of processed soybean oil and diesel fuel. Since soy oil is essentially a byproduct of soybean processing, its price is not as sensitive to the cost of soybeans.
Cost is more sensitive to supply and demand for soy oil.
Since the grid power is available everywhere in Iowa, an engine driven generator would only be used during peak load periods or emergencies. One potential application with a wind turbine would be to use an engine-driven generator to manage a facility's peak demand charges from the utility. The wind turbine would provide power to reduce the facility's energy purchases. A diesel generator could be used during peak load measurement periods while the wind turbine reduces energy purchases. If the wind turbine were not generating during a peak demand period, then the engine-driven generator would be automatically started.