Peter Maloney reports in Microgrid Knowledge that microgrids with gas turbines as prime movers in Alaska and Australia offer mirror images of microgrid capabilities, as explained in this excerpt from Gas Turbine Microgrids: Reliability and Sustainability through Intelligence.
One of the benefits of gas turbine microgrids is their ability to “island” electrical operations from the surrounding grid.
In Sitka, Alaska, the grid is always islanded. The city is the grid, and the city—the largest in the United States in terms of area—occupies most of Baranof Island.
Baranof Island is not electrically connected to the mainland, so all the power for Sitka’s roughly 9,000 inhabitants is produced locally. The power comes from two hydroelectric plants, which give this city on Alaska’s pristine Panhandle the distinction of deriving nearly 100 percent of its energy from renewable resources….
Mirror image in Australia
On the other side of the globe, the City of Esperance, Australia, also operates in isolation. It is not on an island, but it might as well be. The city sits on the south coast of Western Australia State, but is not connected to the grid.
Esperance is also the home of Australia’s first wind farm. The Salmon Beach Wind Farm began operating in 1987, but was decommissioned 15 years later because of urban encroachment. It was replaced by the Ten Mile Lagoon and Nine Mile Beach wind farms. Together they can provide nearly 25 percent of Esperance’s electricity.
Unlike hydropower, however, wind power is not reliable. The primary source of power in the region, an area that extends about 80 miles from the city, comes from gas turbines, the 38.5-MW Esperance Power Station.