ISEP will be a valuable asset, allowing Iowa and the Upper Midwest to produce more environmentally-friendly electricity

With hundreds of millions of dollars invested in construction, the Iowa Stored Energy Park (ISEP) will provide significant economic benefits for the state of Iowa and the Upper Midwest.  ISEP is a joint project of municipal utilities in Iowa and several nearby states.

ISEP will be located in central Iowa, next to a very good wind energy resource.  ISEP will use the energy from wind facilities and other resources connected to the regional electric power grid to store air in an underground geologic structure during time periods of low customer electric demand and high wind.  Then, during peak customer power demands and when the wind is not blowing, the stored air will be released, mixed with natural gas and used to power combustion turbines that produce environmentally friendly and economical electricity.

ISEP will utilize some of the latest innovations in the generation of electricity. Wind turbines, deep underground air storage, and efficient combustion turbines will be used by ISEP to take the variability of wind and turn it into clean energy on demand.  The project will enable utilities and their customers to add more renewable wind energy to their power supplies then they could otherwise.

Compressed Air Energy Storage (CAES) enhances wind power

In a CAES at the ISEP facility, air will be compressed using low-cost, off-peak electricity, and wind that is not being sold on the grid at that time.  The air is stored in a deep underground geological formation for later use in making electricity. When electric  energy is needed and the wind is not blowing, the stored air will be released, heated with natural gas and used to drive generating turbines. The electricity it produces can be used as needed, especially during high-demand peak hours. This process uses less fuel than a conventional natural-gas fired combustion-turbine generating facility.

By using compressed air energy storage and wind power together, an environmentally friendly, alternative energy source is available to homes and businesses.

(Flash 8 is required to view CAES Demo animation). Download CAES demo animation by clicking here.

ISEP History

In 2003, interested members of the Iowa Association of Municipal Utilities (IAMU), a group representing publicly-owned utilities in Iowa cities, formed a study committee to develop the concept of the Iowa Stored Energy Park. In 2005, the IAMU committee passed responsibility for ISEP to the Iowa Stored Energy Plant Agency (ISEPA), an Iowa corporation formed under Section 28E of the Iowa Code.  Today, the members of ISEPA represent 95 municipal utilities located in Iowa, Minnesota, North Dakota, and South Dakota.

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