# Ancillary Service (area regulation) Using Battery Energy Storage vs Pumped Hydro vs Gas Turbine

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#### miguelantonio

I was informed that a battery energy storage system can provide two time its nameplate capacity for regulation. Does this mean that if the three power supply system all have an available 40 MW for ancillary service, the battery can deliver twice as much as the pumped hydro and the gas turbine? Does this mean that the battery energy storage system should be paid double for its service?

Kindly compare the three in terms of being an ancillary service provider to the grid.

Thank you.

#### PhilCorso

Miguel, your query is not simple to answer. As a start, I suggest you obtain the 2012 study by The Global Energy Institute (GENI), authored by Andreas Oberhofer.

Phil

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#### miguelantonio

Hi Phil,

This is the study: Battery energy storage for intermittent renewable electricity production, A review and demonstration of energy storage applications permitting higher penetration of renewables by Steffen Gortz

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#### miguelantonio

Hi Phil,

I was reading through the FERC ORder 755 on how payment for ancillary services are discriminatory because some AS provider actually does more than another provider. Hence, FERC thought just that they be compensated more. Is this what the doubling effect of a battery is? I mean, a battery can ramp up energy pretty quick as compared to conventional power plants. So, if let us say, a 10MW/min ramp up is required by the grid operator it will probably require more two conventional power plants to provide this, but a battery can provide this service by itself. Hence, an energy storage must be paid more than a conventional power plant.

Likewise, am I correct in saying that only an energy storage device like battery, flywheel, etc. can absorb excess energy in the grid? Conventional power plants (except pumped hydro) cannot do this? Could this be another reason why an energy storage device must be paid more for its ancillary service as compared to a conventional power plant?

I hope I am getting nearer to the reason as to why an officer of the transmission grid will say that a battery energy storage system can double its capacity with regards to the capacity payment (albeit it was said unofficially because current ancillary service purchase agreement has no such payment scheme).

Thanks a lot,
Mike

#### PhilCorso

Miquel... obtain a copy of the May, 2015 issue of "Power Magazine", pages 22-25.

It contains an article titled, "Batteries Are Carving Out Space on the Grid" revealing Southern California Edison's (SEC) installation of a 260 MW storage-resource. It uses Li-Ion Batteries and will cover about 50% of SEC's 2020 commitment.

Regards,
Phil