If you want to see how the power grid could become smarter in the future, then you might look at a university “micro-grid” in action. Several schools are now building self-contained networks of energy generation, power storage, and demand control. And they’re showing how compact, local grids could reduce outages, improve efficiency, and integrate renewable energy sources effectively.
One example is the project at Santa Clara University in California. Its micro-grid can exist completely independently of the main network, so classrooms would remain powered up even when the rest of the city is down. It incorporates on-site solar power together with renewable energy from the local power company. Soon it will also include both a cogeneration plant and a biodigester that generates electricity from food waste.
The network is based around a series of controls that let Joe Sugg, assistant vice president of university operations, balance out supply and demand. For example, if he can’t rely on the solar panels because the sun isn’t shining, he can slow down the air-conditioning units, chillers, or plugs in some buildings to reduce demand. That means the university doesn’t have to buy extra power at peak times when electricity prices are highest. Sugg estimates this flexibility saves 10 percent on overall energy costs.
The university can also work with the municipal utility Silicon Valley Power if the latter is having trouble meeting its own customer demands. Sugg can reduce the campus’s energy consumption by about a fifth (1 megawatt out of about 5 megawatts) if required. That in turn allows the utility to rely less on reserve stations, which usually produce the dirtiest type of electricity.
“It gives them a way to shut their coal reserve plants, which makes them more cash-flow positive and carbon neutral,” Sugg says.
Sugg points out that California has the worst record for outages in the country. It makes sense therefore for the university to have a backup system that lets it operate independently of the grid. “About 75 percent of our revenue comes from students. If we can’t keep our classrooms open, we don’t have a university. It’s a business continuity question,” he says.
Universities, along with military installations, have been early adopters of micro-grids (UC San Diego has a big project, for instance). The next stage will be for cities to take on the concept, according to a recent report from GTM Research. By adopting micro-grids, it says, cities can insulate themselves from trouble in the wider system and take advantage of falling prices for renewables and natural gas.
“We’re not going to meet our future energy demand without huge changes in our long-haul transportation of getting electricity from A to B,” Sugg says. “With distributed generation, we can bring it nearer to the site [where it’s needed], and that’s what micro-grids provide.”