The future of the power grid is here, and it’s in a California jail.
A new distributed energy project at Santa Rita Jail in Dublin, Calif., uses power generated on site from fuel cells, solar panels, wind turbines and diesel generators to form a “microgrid” that can keep power going when storms disrupt power from the main grid, according to MIT’s Technology Review, which published a story on the system. Unlike a regular emergency backup system, which represents an added expense, the microgrid also saves the jail about $100,000 a year.
Coordinating power from intermittent sources like wind and sun, while also determining when to power up other sources or pull electricity from the main grid, requires the microgrid to do a lot of thinking. Among other things, it needs to adjust the frequency and voltage of power from various sources, adapt to sudden changes in the amount of energy the system is generating and communicate with the main grid so that it can send more power to the utility when it’s experiencing high demand from other sources. The system can also adjust the amount of power being used by the jail, for example decreasing the use of air-conditioning, when the main grid has a demand spike.
Microgrids are gaining attention from businesses — like jails — that can’t risk a blackout, as well as from remote locations that can’t access the grid. But as their cost decreases, they may become more attractive elsewhere as well.
Technologies used in microgrids also translate to larger-scale settings as utilities adopt smart grid technologies to integrate distributed generation sources and adapt to rising, volatile demand. Technological advances, including “smart batteries” that communicate with the grid and smart meters that are already installed in many homes, are making deeply integrated systems using a variety of power sources increasingly common.
Main photo credit: Alameda County