Most people know what an electric grid is -–basically it's power generated centrally by the utility companies from a variety of energy sources like oil, gas, nuclear, coal, and then transmitted at high voltages via overhead and sometimes underground transmission lines to local substations where the voltage is reduced down to the distribution voltage level and distributed over power utility lines to homes and businesses.

It’s called a “grid” because there is a network of wires that move the power around from node to node –basically a combination of power source, wires and controls. A micro-grid is the same concept but on a much smaller scale. One example of a microgrid is a complex of buildings on an island. This complex of buildings may have one outbuilding that has a central power plant which almost always used to be powered by diesel. Now many are solar with batteries and have also have a backup generator, often powered by diesel. So these power plants have a combination of solar diesel and maybe wind and sometimes batteries, and then they have wires going from this power plant to power multiple buildings on the island. Another example of a microgrid is one you might have in your pocket. Think about a cell phone. It’s got a battery, sometimes a backup battery, and you might have a mini solar charger. Those thinks are a microgrid.

So we have different scales of microgrids, but why so much interest in microgrids lately?

Listen up to this week’s Energy Show to learn more about microgrids and the importance they are playing in the changing landscape of central and distributed energy.