If you're a Californian seeking to reduce your fossil fuel consumption, you have a number of ways you can go about it. You could take mass transit, ride a bicycle, or buy a hybrid car. You could insulate your home and get more efficient appliances. You could install rooftop solar.
Or you could hold up a liquor store in Oakland.
As a post by Kevin Bullis in today's MIT Technology Review reports, Alameda County's 4,000-inmate maximum-security jail at Santa Rita has just completed initial work on a distributed energy microgrid, which connects the jail's solar panels, fuel cells, and wind turbines -- as well as more conventional sources of spot power such as diesel generators -- into a system that allows the jail's power to stay on even when the main transmission grid fails.
Microgrids are an emerging solution to a few consistent problems with electrical power distribution as we know it. They offer reliability in a time where the national grid is becoming incresasingly brittle: a microgrid's operators can keep customers -- or inmates, as the case may be -- provided with power during mass blackouts by simply throwing a switch to disconnect from the larger grid.
They can also save consumers a lot of money, by buying grid power when it's cheapest and running on their own generation capacity during more expensive peak periods. The Santa Rita Jail reports expected savings of $100,000 a year.
Lastly, microgrids offer an incremental solution to the issue of renewable power intermittency: high-tech microcontrollers can regulate fluctuating power flow, and battery storage can provide a hedge against times when the wind dies down and the sun hides behind a cloud. The Santa Rita Jail system runs microcontrollers at each generation site, and industrial lithium-ion storage batteries capable of holding 4 megawatt-hours' worth of power.
With their remotely-controlled locks, surveillance-dependent security and generally disgruntled population, jails are definitely one place where a power outage can lead to utter catastrophe. Field-testing a microgrid at a facility that needs power 24/7 makes perfect sense. But there's something about this test taking place in our incarceration-prone state that gives a bit of an "Only In California" tinge to the Santa Rita Jail's pioneering project.