Imagine all the electricity in a city — day and night — coming from the sun. The U.S. Department of Energy (DOE) is.
But imagination is about as far as one can go right now. There are a lot of potential problems with integrating a massive amount of solar power into the energy infrastructure of today, and that’s why the DOE is offering up $25 million to develop big data analytics, smart devices and other tools that could make 100 percent solar possible.
And the types of solutions the department is looking for would do more than just help integrate solar power. They would give grid operators more data and more control. After all, it’s not just price standing in the way of solar power — it’s a creaky old grid that doesn’t respond well to change.
With a May 2 announcement for a program called Enabling Extreme Real-Time Grid Integration of Solar Energy, the DOE laid out some of the biggest barriers to high-penetration solar power. Minute-to-minute swings in solar power generation can cause shifts in voltage that are potentially destructive to infrastructure along the grid, but analyzing those swings can require data — basically, measurements for every minute of an entire year. Meanwhile, grid operators face the lack of ability to monitor those power swings because they often lack the ability to monitor what’s happening on a grid beyond any individual substation. And while rooftop solar can put surplus electricity onto the power grid, the infrastructure that delivers electricity was only designed to flow in one direction.
There are potential technological and operational fixes to all those problems, and the DOE thinks they can happen soon. Big data analytics could handle the high-resolution studies needed to determine voltage swings, while software could use solar forecasts to help predict generation. Smart inverters could send information to grid operators about individual solar arrays, while computer modeling could use that data to paint a picture of wider trends.
Part of the grant money is for technology the department wants to see ready to handle 50 percent solar power by 2020, and the other part is for technology that could handle 100 percent solar power by 2030. Project awardees would need to do field tests with utilities to demonstrate how they work.
Not that the DOE expects the whole country to be powered only by solar by 2030 — no, the department is aiming for solar to expand from 1 percent of the market today to 14 percent by 2030. Even the Solutions Project from Stanford University, which developed a plan for the U.S. to source all of its electricity from renewable resources, only called for about 48 percent solar.
But a key facet of solar power — as well as wind power, and to a lesser extent hydropower — is intermittency. The sun doesn’t always shine, the wind doesn’t blow constantly and during droughts, the power generation from dams falls. So if solar were to make up a large part of the grid’s power supply, it could at any given time be a small portion of the electric generation mix, or a very large part.
And in fact, many are anticipating that the U.S. could reach a point called “grid parity” — perhaps even soon — when solar power will be price competitive with fossil fuels. At that point, it’s possible that people start putting photovoltaic arrays on their roofs en masse, and that’s when the DOE’s technology would come into play.
Solar aside, the technology the department is looking for smacks very much of the buzzing “smart grid” industry. For example, many grid operators lack the ability to “see” when there’s a power outage and rely on customers to report them individually. Even then, a power company might have trouble figuring out where the problem is.
So the idea of improving an operator’s “visibility” along the grid, as the department is describing, could help identify blackouts and find where problems exist faster.
For more information on the ENERGISE project, click here.