The emergence of the smart grid has raised concerns about cybersecurity among utilities; two-way digital networks are more vulnerable. But according to utility executives, distributed power generation technologies, such as solar, particularly combined with energy storage, could help minimize the impact of an attack.
Jim Rogers, CEO of Duke Energy, (s duk) said during a panel discussion at the Solar Power International conference in Dallas last week, that the idea that solar and storage could help shield the grid has been floating around for some time now. The U.S. Department of Defense likes the idea, because having localized, and even portable, power generation systems can cut the reliance on power delivered via transmission lines from afar.
“Because of the fear of cyber attack, the ability to seal off part of your grid is important,” Rogers said. “If solar is properly distributed across the system with the right battery technologies, then that could lead to a place that enhances reliability, not taking away from it as the current conventional wisdom would suggest.”
That’s a counter intuitive idea, and one that also can be useful in events of natural disasters. Solar panels have been a popular choice for off-grid energy sources, and in recent years, it has been popping up more quickly on residential and commercial rooftops and connected to the grid. Because it only produces power during part of the day, it’s not desirable as the main source of power for utilities, whose responsibility is to provide reliable and affordable power around the clock. Adding energy storage, such as batteries, can allow homes and businesses to use solar electricity after the sun goes down.
If a cybersecurity breach disrupts the delivery of power, most of which comes from fossil fuels — nuclear and hydro power plants — then solar (or other power generation technologies such as fuel cells and small wind turbines) could provide power for some time to, say, a neighborhood, while repair takes place on the grid.
Making it work
It will take a lot of planning, money and technology development to make the idea work, however. Note that Rogers talked about the need to think about where to position solar generation in different parts of the distribution grid and to have the right energy storage equipment. Where residential and commercial solar installations take place depends on whether home and business owners want them.
Some utilities, such as Duke, Pacific Gas and Electric and Southern California Edison have installed solar arrays on leased, private commercial rooftops or next to their substations or properties that are close to communities. Prologis and NRG Energy (s nrg) are working on a 733 MW project to install solar panels on commercial rooftops in many states and sell the power to local utilities.
Using batteries to bank renewable energy is a new phenomenon, and utilities are just starting to do field trials to see which technologies work best and how to marry them into their generation and distribution systems.
Utilities also have to figure out how to seal off pieces of their distribution grids. Southern California Edison is working on projects to figure out how to connect the circuits in ways that will create these micro-grids. A circuit is a distribution line for connecting homes and businesses to the nearest substation, which receives electricity from power plants and modifies its voltage before sending it to customers. Each circuit serves 2,000 to 2,500 customers.
Though the goal is to allow Edison to quarantine problems so that it could fix them without interrupting power services in other parts of its territory, the research also could help to make sure power continues to flow into some neighborhoods after a cyber attack happens.
Photo courtesy of Eagle Roofing