"Mitsubishi Heavy Industries, Ltd. (MHI), jointly with Scottish Hydro Electric Power Distribution (SHEPD), has begun an energy storage system demonstration project using the distribution grid in the UK's Orkney Islands, which has a high penetration of renewable energy. The project aims at demonstrating power supply stabilization in the region by introducing a container-housed large capacity energy storage system using lithium-ion rechargeable batteries, with a power output/input capability of 2MW (megawatts). The storage system will be handed over for operation in the middle of 2013.

The demonstration project is conducted with the support of New Energy and Industrial Technology Development organization (NEDO) of Japan, under the ""Development of Technology for Safe, Low-cost, Large-size Battery System"" programme. In the project, Mitsubishi Power Systems Europe, Ltd. (MPSE), the business base for MHI's power system operations in Europe, will jointly provide the energy storage service to Scottish Hydro Electric Power Distribution plc (SHEPD) The funding for the project is being provided to SHEPD from OFGEM, under it's Tier 1 Low Carbon Network Fund.

The energy storage system, which has the capacity to store approximately 800kWh (kilowatt hour) nominal, 500kWh normal usage, consists of two 40ft containers for the batteries and a 40ft container for the power conditioning system. Each battery container houses more than 2,000 units of lithium-ion rechargeable batteries and its management system. The power conditioning system container houses a system for conversion of direct current (DC)/alternating current (A/C) and the associated input/output controls.

The energy storage system will be installed at SHEPD's Kirkwall Power Station. In the cases of power shortage or power surplus on the Orkney Islands, power is transmitted from/to the mainland through two 33kV submarine cables. When there is too much renewable energy, exceeding the export capacity of the cable to the mainland, the energy storage system will import part of the excess energy, reducing the need to constrain renewable generation on the islands, by reducing or stopping generator export."


Lithium-ion Battery