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Peaker Power Plant Fact Sheet

Nationwide, including in Illinois, a number of new natural gas burning power plants are being built and more plants are being proposed. The Illinois EPA has expended significant time and effort over the past eighteen months on the issue of peaker power plants and carefully considers each application. This fact sheet addresses some of the basic questions asked about peaker power plants.
Q What is a peaker power plant?
A New peaker power plants being proposed in Illinois use turbines that burn natural gas to produce electricity. They are called peaker power plants because they are generally run only when there is a high demand, known as peak demand, for electricity. In Illinois, this occurs during the summer months when air conditioning load is high, and the nuclear and coal burning power plants cannot meet the demand for power. Peaker plants generally run only during peak periods when utilities will pay higher prices for electricity because it is more expensive to produce electricity by burning natural gas. Peaker power plants cannot compete with the cost of electricity produced by nuclear and coal burning power plants.

Where are these plants being built?

A In general, the plants are being located where large capacity power lines and gas pipelines cross or are in close proximity to one another.
Q Are these facilities regulated by the Illinois EPA?
A Yes, the Illinois EPA administers rules that limit the air emissions and, if present, direct water discharges from peaker power plants. The Illinois EPA does not have the authority to consider other issues related to the siting of a proposed facility, (e.g. need for a proposed power plant, aesthetics, etc.) during permitting.
Q What will be the health impact of a peaker power plant to people living around the facility?
A The evaluations of new peaker power plants for which the Illinois EPA has received permit applications to date have indicated that the plants will not have a measurable impact on air quality. If a source does not have a measurable impact on air quality, there should not be a health impact. To confirm that proposed plants would not impact air quality, the Illinois EPA has been asking all peaker power plants to submit air quality modeling even though this is not expressly required by the rules for minor sources.
Q What does the Illinois EPA review in a permit application?
A Permit applications are reviewed to determine whether the information presented in the application shows compliance with applicable rules. Permits are prepared with detailed conditions that identify applicable rules and require appropriate testing, monitoring and recordkeeping to verify compliance with applicable rules.
Q These plants will emit almost all of their emissions over a small number of days during the summer. Why can’t they be considered major sources under the federal Prevention of Significant Deterioration (PSD) rules?
A The proposed peaker power plants whose potential annual emissions are below the applicability thresholds of the federal PSD rules are not subject to PSD because the rules define "major sources" in terms of annual emissions from a proposed new source, not monthly or daily emissions. However, as noted above, the Illinois EPA is requiring applicants for "minor" peaker plants to perform air quality impact modeling as if the plants were subject to PSD. The Illinois EPA also has exercised its discretionary authority and is holding public comment periods for all proposed plants before taking final action on a permit. In addition, the Illinois EPA will continue to review the situation.
Q Can the Illinois EPA place a moratorium on the issuance of permits to peaker power plants?
A The Illinois EPA does not have the legal authority to impose a moratorium on the issuance of permits to peaker plants. In fact, the Illinois EPA is required to process the permit application for a new plant within 180 days.
Q Does the Illinois EPA have some say in the location of these facilities?
A The Illinois EPA does not have a role in the local siting process. Currently there is no state siting requirement for these types of facilities, in contrast to new pollution control facilities such as landfills or wastewater treatment plants. However, even the siting provisions for pollution control facilities leave the decision to the local government in which a proposed facility is to be built.
Q Can the Illinois EPA issue a permit for a new power plant prior to the company getting zoning approval from the local municipality?
A Yes, the Illinois EPA’s decision is totally separate from local zoning decisions. Illinois EPA’s approval of a permit does not mean that the proposed power plant should be granted local zoning approval, and conversely local zoning approval does not mean that a plant will be issued a permit by the Illinois EPA. The Illinois EPA’s decisions are based upon the air (and, in certain instances, water) pollution control regulations. Local zoning is based upon other factors including impacts on land use, property value and the local economy.
Q If a company gets a permit from the Illinois EPA, can the company build even without local approval?
A No, the company must build on a location that is appropriately zoned for a power plant. In some cases, the location is already zoned for a power plant; in other cases, the company must obtain a special use approval to build a power plant. In either case, the Illinois EPA's permit does not have any bearing on the local zoning decisions.
Q If a proposed plant has a permit from the Illinois EPA, does that mean that the facility is "ok" and the local municipality must give the company approval to build?
A Absolutely not. The role of the municipality is different from the Illinois EPA’s role. The local municipality must decide whether a proposed facility is appropriately planned and sited, given its role in local land use management.

An issued permit is stating, in effect, that the company’s application shows compliance with the state and federal Air Pollution Control regulations. It is not stating that the facility will comply with other requirements or standards, including local zoning.

Q Even though the Illinois EPA is not involved in zoning, doesn’t the Illinois EPA take into account proximity to residential areas when issuing a permit?
A As a practical matter, environmental permitting rules assume that all facilities are being built in residential areas even if an area is currently agricultural or industrial in character. As a result, the Illinois EPA's review of the permit is independent of local land use.
Q How can we be sure that these plants won't run all year?
A Although the Illinois EPA's permits do not limit the plants to running only during the summer, they do have limitations on how many hours the plant may be run during the year or how much fuel they can burn. The Illinois EPA monitors facilities’ compliance with their permit conditions and if violations are found undertakes enforcement actions.
Q These plants would run when ozone air quality is the worst. How can the Illinois EPA allow new peaker plants to locate in the Chicago ozone nonattainment area where air quality is already "bad" during the summer?
A Illinois has made substantial progress in improving ozone air quality in the greater Chicago area, reducing both the extent and magnitude of exceedances of the ozone air quality standard. These new peaker power plants should not interfere with continuing reductions in ambient ozone levels and attainment of the ozone air quality standard. While these plants do emit nitrogen oxide (NOx) which is a precursor to formation of ozone, reductions in NOx emissions are occurring from existing sources such that a substantial decrease in overall ambient concentrations of NOx is occurring in the area. Moreover, the new plants must meet stricter emissions requirements than older plants. In this regard, it should be noted that because ozone is formed by chemical reaction in the atmosphere, the emissions from the new plants will participate in ozone formation many miles downwind rather than at the point at which they are emitted. However, the downwind impacts are being addressed through a national strategy that will include all power plants. In any case, NOx emissions from the new plants would be contributing only a very small part of the overall loading of ozone precursors.
Q Does the permit issued to a peaker power plant regulate noise levels?
A While the state's noise regulations establish property-line limitations for noise levels, they do not require sources to obtain permits. Nevertheless, we advise facilities such as peaker power plants to utilize noise abatement technology. While the Illinois EPA does not directly enforce the noise regulations, local authorities are empowered to do so, and the Illinois EPA provides technical assistance as necessary. The contact person for noise at Illinois EPA is Greg Zak, who can be reached at 217-782-3397.
Q What pollutants does a peaker power plant emit?
A The pollutants emitted by peaker plants are the pollutants associated with burning of natural gas for any purpose. The greatest emissions from peaker plants are nitrogen oxides (NOx). Other pollutants emitted include carbon monoxide and, in much smaller amounts, particulate matter, volatile organic material, and sulfur dioxide. These pollutants at proposed levels have no meaningful impact on air quality. NOx emissions from new peaker power plants are minimized by the use of low-NOx burners or water injection into the burners. The low rate of NOx emissions, combined with excellent dispersion, means that the plants would generally have no measurable effect on local NOx air quality.
Q Will these plants burn any fuels other than natural gas?
A Some of the peaker power plants are being developed with the ability to burn distillate fuel oil. This will allow these particular plants to operate when natural gas is not available. This could be especially useful in the winter time, when natural gas supplies are being used for heating, if a peaker must be called into service as a result of an unexpected outage of an existing power plant.
Q Who can I contact for more information?
For more information on emissions or permitting status of peaker power plants in Illinois, contact:
Brad Frost
Illinois Environmental Protection Agency
1021 North Grand Avenue East
P.O. Box 19506
Springfield, IL 62794-9506
217-782-9143 - TDD phone number
1-888-372-1996 (please leave a message)
Q For more information about this or other fact sheets contact:
Public Information Officer
Illinois EPA, Bureau of Air
1021 N. Grand Ave. East, Box 19276
Springfield, IL 62794-9276
217-782-9143 - Hearing impaired

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