Fuji Electric Co Ltd announced Dec 24, 2013, that the company and NBK Corp (Minato Ward, Tokyo) have received an order for a new micro-grid system from Tonga Power Ltd.
It is intended for the "Project for Introduction of a Micro-Grid System with Renewable Energy for the Tonga Energy Road Map under the Grant Aid." And this will be the first micro-grid system that Japan will export as a grant aid.
Specifically, Fuji Electric and NBK received an order for the micro-grid system and a 1MW soler power generation system. They will be installed on Tongatapu Island, the Kingdom of Tonga. And the installation is scheduled to be completed in March 2015.
When a large-scale renewable energy-based (solar, wind, etc) power generation system, whose output tends to fluctuate, is introduced to a relatively small-scale power grid such as for islands, it becomes difficult to stably supply electricity. Also, the fluctuation of the frequency of the grid makes it difficult to maintain electricity quality.
To solve such a problem, a micro-grid system (1) performs a high-speed charge and discharge control of a power storage system in accordance with the state of the power grid, (2) maintains electricity quality by reducing the fluctuation of the output of a renewable energy-based power generation system and (3) enables to introduce a large-scale renewable energy-based power generation system.
Thus far, Fuji Electric has participated in many operation tests including the test of a micro-grid system for isolated islands in the Kyushu-Okinawa area. With such experience, operation tests of community energy management systems (CEMSes) such as in Kitakyushu City and technologies for power storage systems for wind power generation plants, the company has built up know-how on ensuring a balance between demand and supply as well as electricity quality (voltage and frequency) for an entire community.