Informational

The Power of Microgrids

By Grant Faber, SEMREO Intern and UM Student

A basic example of the structure of microgrids - Source

A basic example of the structure of microgrids – Source

Many people think of renewable energy, like residential solar PV, as a hedge against unreliability of utility-supplied power. In fact, though, most of the solar power (95%) installed in Michigan does not work when the electric grid goes down. This is a safety measure that prevents solar PV systems from sending excess power to the grid (as they do with net metering, which essentially uses the utility grid as a battery and allows those with solar PV systems to sell excess energy produced during the day back to the electric grid and draw more at night when the sun is not shining) when utility linemen are working to restore power during an outage.

The solution to this problem is the implementation of microgrids, which can “island” one or more interconnected power users from the grid when it goes down. A microgrid requires distributed power generation capacity foremost and may also require energy storage capacity, such as large batteries, if the system might generate more power than the island is using, as can happen during daylight hours with solar PV.

According to General MicroGrids, “A microgrid is a discrete energy system consisting of distributed energy sources (including demand management, storage, and generation) and loads capable of operating in parallel with, or independently from, the main power grid.” The ability to connect and disconnect from the main power grid as needed gives an extra level of flexibility.

Recently, public purpose microgrids, or community microgrids, have been emerging across the country. These involve distributed energy generation and storage in municipal and local contexts. When used in this way, microgrids can provide emergency preparedness by powering vital community necessities during power outages. These necessities can include facilities such as community centers, police stations, fire stations, cell towers, emergency communication centers, town halls, and military bases.

New York State is currently constructing a microgrid for the Empire State Plaza, which contains the New York State Capitol. This microgrid will power the Capitol in case of a large-scale power failure, allowing the state government to continue operations even during a catastrophe. One can imagine similar uses at police stations and community centers across the country, especially with the recent Hurricane Harvey that caused power outages across Texas. Greentech Media published an article about the importance of microgrids during disasters and one supermarket chain in Texas that was able to remain open after the hurricane using microgrids here. Renewable energy combined with storage allows for sustainable backup generation, increases overall grid resiliency from fewer demands on the grid, and improves community safety in the event of catastrophes.

According to David Konkle of the Great Lakes Renewable Energy Association, Michigan currently only has two microgrids in use: one at the University of Michigan and another at Fort Custer. He also notes that there are Department of Energy grants available for battery storage and microgrids, which could be a good avenue for bringing federal dollars into the state of Michigan.

As renewable energy becomes increasingly popular, so too will distributed energy resources such as microgrids. Their popularity depends on awareness, however, so it is important to spread the word about the awesome potential of microgrids and consider adding battery storage whenever constructing a renewable energy project.

SEMREO offers grant seeking and administration services for municipalities that are seeking grants for energy projects, such as microgrids. Please visit http://regionalenergyoffice.org/what-we-do/grant-seeking-administration/ for more information!