Borrego Springs sprawls across a mostly flat desert valley about 80 miles east of San Diego. When the afternoon wind blows in the summer it feels like an oven door has opened nearby. The remote location is both an attraction and a challenge.
“We are 50 miles from another community that has a big box store. We are 30 miles from the nearest gas station if our power goes out,” Linda Haddock said.
She has lived here for about 10 years where daytime temperatures can languish above the century mark for long periods during the summer. That creates a voracious appetite for power, Haddock said, an appetite that has at times pushed her monthly power bill over $1,000.
“Our electric bills soar in the summertime,” Haddock said. “We live in the desert. If the temperature is going to be 120 outside. It’s going to be 160 in your car. The ground is 180. It’s not going to cool down that much at night.”
Haddock’s gated resort community is a cluster of manufactured homes surrounding a green golf course. A swamp cooler, which humidifies the air in her home, keeps the trailer cool most of the time. But in the summer, she needs traditional power-hungry air conditioning to keep the heat in check.
The electricity that feeds her appliances pulses through a single high-voltage power line that comes from San Diego. That San Diego Gas & Electric line climbs over a treacherous mountain range.
In September 2013, a storm took out 19 SDG&E power poles, severing the town’s electrical umbilical cord.
“Lightning took them out. It wasn’t anything anyone did. Lightning just took out the poles. It is when our monsoon season is. Stuff happens,” Haddock said. “We were informed by SDG&E by this outage, by this issue of trying to get to the poles and get us back up, that it was going to be three to four days.”
An outage that long, put lives at risk.
Utility officials scrambled to get the power back on. Their attention turned to a large solar farm on the edge of town. There, rows of photovoltaic panels sit on brackets several feet off the ground.
“This is a single access tracking solar field. So the panels are actually tracking the movement of the sun. Right now, there’s a motor that’s actually turning all the panels,” SDG&E’s Neal Bartek said.
The panels can generate enough electricity to turn on the power in 26,000 homes. Work crews rerouted that power in 2013 to keep electricity flowing to Borrego Springs while the power lines were repaired. That was essentially the birth of the region’s microgrid.
“What the microgrid allows us to do is to have some resources locally here so that if damage occurs to that line, we can use local resources to power that community,” Bartek said.
But solar isn’t the only key to developing a power island, like this one. SDG&E added diesel generators to bolster reliability and engineers installed a power storage facility.
Inside several short white trailers, air conditioners are always on. The cool air keeps racks of lithium ion batteries cool.
SDG&E’s Hanan Eisenman said the batteries have a couple of jobs.
“So what we do with batteries is we store that renewable energy in the middle of the day when the sun’s out and then we can release it into the grid in the evening times,” Eisenman said.
If a cloud moves over the solar farm during the day, the batteries make up for the dip in energy production. That keeps the flow of energy to either the town or the grid, steady and predictable. It also demonstrates the microgrid concept is viable.
“We wanted to create a project where we could see how all those new technologies coming onto the grid, affect the grid and how we can leverage those new technologies to create opportunities for our customers to be more sustainable, to be cleaner and also to provide more reliability,” Eisenman said.
Getting all the power supplies to work together is the key to success.
Eisenman said this project works because the region is isolated and there’s a need to deal with a fragile delivery system, but microgrids don’t have to be isolated. In fact, there’s one already working in urban San Diego.
UC San Diego uses a number of renewable power sources to satisfy the thirst for electricity on the school’s sprawling campus.
“What we have here is a 2.8 megawatt fuel cell. Right here, are the stacks of the fuel cell, they produce 1.4 megawatts each,” said John Dilliott, UCSD’s facilities engineer.
The university has invested heavily in power that’s generated on the campus where it is used. The fuel cell, solar panels and a cogeneration plant meet more than 90 percent of the campus’ power demand, Dilliott said. That was just one piece of the school’s microgrid puzzle.
“You need to be like a self-contained organization like us that has centralized our utilities,” Dilliott said.
In some ways the campus microgrid is the result of money saving decisions. The school was looking at opportunities to cut its power bill. Through grants and technology improvements, university officials ended up accumulating generating capacity.
At a certain point, school officials saw that they could power the campus without the grid.
That’s a pretty big jump from just saving several million dollars a year.
Another factor comes into play. Dilliott said steady reliable power is a crucial resource at a major research university and he said it is hard to reconcile critical research materials. In one set of freezers the school stores ice core samples from the Arctic that are hundreds of years old. Those are irreplaceable assets.
“There are a whole bunch of freezers around campus that store samples of all kinds of stuff at really low temperatures. Negative 80 Celsius. Without power they can hold their refrigeration for a little bit but not very long,” Dilliott said.
A lot of critical research work was put into jeopardy when a power outage in Southwestern United States persisted for hours in September 2011. Operator error destabilized the grid and caused cascading shutdowns in California, Arizona and Baja California, Mexico.
UC San Diego went dark, but the outage was different on campus.
“Even though we lost power during the power outage. We were able to restart our power generation. They call that ‘black starting.’ We did have the ability to do that. Even though the utility was out for 8 to 12 hours, we were only out for about 4 hours,” Dilliott said.
Blackouts have touched other parts of the country. The Northeast in 2003. The East Coast during Hurricane Sandy in 2012 and the nation’s mid-Atlantic states during another storm that same year. The power grid’s age and fragility has a lot of researchers and engineers trying to figure out ways to update the system.
Jeremy Del Real works at the Center for Sustainable Energy in San Diego and he thinks microgrids could be a bridge technology that helps ease the outdated grid into the modern age.
“The microgrid can actually work with this antiquated system and actually alleviate that pressure and some of the stress that these renewables and these technologies alone would kind of put on the grid. So it helps to better integrate these technologies with an aging infrastructure,” Del Real said.
The idea of sustainable electrical power systems that generate their own electricity has a big future, Del Real said. He also quickly acknowledged that it is easier to talk about the idea than it is to put the idea into practice because there are plenty of hurdles in place.
“It will become more prevalent in certain locations,” Del Real said. “I think you’ll see, at the community level, microgrids starting to develop as they kind of work through those barriers, you know, on the regulatory side and some of the economic barriers that kind of exist now.”
Del Real said utilities are another key hurdle as power companies adjust to a shifting landscape. Utilities will have to get used to a world where power generation and control of power resources is in different hands.
Meanwhile, the Obama administration launched an initiative this year that actively invests in new grid technologies. The administration is banking on the idea that a host of new technologies will help modernized and upgrade the grid. One byproduct could be the creation of even more self-sustaining microgrids.