The Illinois Environmental Protection Agency is out for comment until Oct. 12 on a draft air construction permit that would allow Elgin Energy Center LLC to add oil-burning capability to its existing peaking power facility in Elgin.
This will enable the facility to provide electricity at times when the supply of natural gas for the facility is restricted or curtailed. The Illinois EPA has reviewed Elgin Energy’s application and made a preliminary determination that the application meets applicable requirements.
The Elgin Energy facility was developed to function as a peaking power plant. It has four simple-cycle combustion turbine generators. The turbines are identical models and each has a nominal electrical capacity of 135 MW. These turbines currently only have the capability to burn natural gas. The proposed project would involve installation of dual-fuel burners in the turbines to also enable oil, i.e., ultra-low-sulfur diesel (ULSD) fuel, to be burned.
The planned addition of oil burning capability to the facility would not change the function of this facility as a peaking power plant. It would enable the facility to provide electricity during periods of very cold weather when the supply of natural gas is restricted or curtailed.
As part of this project, water injection, an add-on control technology for emissions of NOx, would be installed on the turbines for use when burning oil. NOx emissions will continue to be addressed with low-NOx combustion technology when natural gas is burned. Low-NOx combustion technology is very effective in preventing the formation of NOx in large, modern turbines burning natural gas.
Water injection is needed because low-NOx combustion technology is not as effective for oil as it is for natural gas. Water injection lowers NOx formation in a turbine by introducing water into the combustion zone of the burners. This lowers flame temperatures, thereby reducing the formation of thermal NOx.
As part of the permitting of this project, Elgin Energy has also requested that tuning of the turbines be addressed. Tuning of the combustion systems of the turbines is conducted to adjust for efficient operation in the upcoming operating season. While a turbine is being tuned and adjustments are made to the combustion settings, emissions of a turbine may be higher than during normal operation. The turbines will be tuned while burning natural gas. Tuning will typically be conducted twice a year, once prior to the summer operating season and once prior to the winter season.
Company contact information is: Elgin Energy Center LLC, Attn: Robert Rapenske, 1559 Gifford Road, Elgin, Illinois 60120.