WASHINGTON, D.C. -- Beech Ridge Energy LLC applied recently at the West Virginia Public Service Commission for approval to install battery storage systems at its wind farm in Nicholas and Greenbrier counties.
The company is asking the commission to waive any requirement that Beech Ridge obtain a modification or amendment to its existing siting certificate in connection with the planned installation of an energy storage device (ESD) at the Beech Ridge Wind Farm that is currently in operation. In the alternative, if the commission finds that the proposed modification is material, Beech Ridge requested that the commission enter an order modifying Beech Ridge’s siting certificate to allow construction of the proposed ESD.
The combined wattage of the BRE I project, which the ESD project would be attached to, the separately certificated Beech Ridge Energy II LLC project and the proposed ESD will not exceed 186 MW of generation, which was previously approved by the commission in this case. At present, BRE I has constructed 67 turbines, producing 100.5 MW.
The ESD will have a combined nominal output of up to 32.4 MW, comprised of eighteen 1.8-MW modules consisting of lithium-ion batteries, inverters, transformers and cooling systems. The lithium-ion batteries used in the ESD are the same kind of batteries used worldwide in a variety of applications, including cordless power tools and battery powered or hybrid vehicles. The batteries are grouped into battery packs or modules that are loaded into trays and the trays are mounted in floor-to-ceiling racks inside a standard shipping container.
Each 1.8-MW module includes: one standard shipping container housing four battery strings; four 450 kW inverters to convert power between direct current and alternating current; a chiller to cool the battery containers; and a transformer for the inverter.
The ESD will produce 480 V output that will be converted to 34.5 kV by padmount transformers inside the battery yard. The battery yard will be connected to the Wind Farm substation by a short overhead line (4,000 foot) or an underground cable that will lead to a new 34.5 kV breaker and switches to be installed in the Wind Farm substation. The construction process will involve minimal site work due to the location of the ESD adjacent to the site of the Wind Farm’s substation, which is already constructed.
“The purpose of the ESD is twofold: to regulate the ‘ramp rate’ of the Project and to provide automatic generation control (‘AGC’),” said the company in its Feb. 14 application. “The Project will gain the capability to regulate its own ramp rate, controlling the rate at which power output from the Project to the grid changes. For example, the ESD will be able to store energy generated by the wind turbines, and release it when appropriate. Additionally, the AGC capability will enable the Project to provide the ancillary service of ‘Regulation’ by increasing or decreasing its power output. Regulation helps PJM Interconnection, L.L.C.(‘PJM’), the grid operator, to match generation levels with short-term changes in electricity use in order to maintain stable grid frequency at 60.0 Hz. The resources selected to provide Regulation in each hour earn a payment based on the amount of flexible capacity being provided. The market-based payment to each resource, known as the ‘regulation market clearing price,’ is determined hourly by PJM based on the set of resources offering and clearing in the market. The Project will earn revenue through its participation in the PJM Regulation market. The Project’s participation in this market is authorized under the Project’s authorization by the Federal Energy Regulatory Commission (‘FERC’) to make sales at market based rates.”
The estimated cost of the ESD is $20m. Beech Ridge said it intends to transfer the portion of the siting certificate that concerns the ESD to Beech Ridge Energy Storage LLC (BRES), which will be a wholly-owned subsidiary of Beech Ridge and will own and operate the ESD assets. The BRES transfer enables the ESD to be financed separately from the BRE I project.
This article was originally published on GenerationHub and was republished with permission.
Lead image: Wind turbines via Shutterstock