乐播传媒

Power Switch

An 鈥渋nterstate for electrons鈥� could revolutionize the American energy grid

Could a breezy afternoon on Colorado鈥檚 eastern plains power downtown Chicago? Or sunlight from Phoenix electrify Seattle on a cloudy morning? What if wind and solar power could be made mobile, cheap and renewable? Oh, and help the U.S. cut its energy sector carbon emissions by up to 78 percent by the year 2030?

This seemingly futuristic vision of America鈥檚 energy grid is not just the stuff of science fiction, thanks to researchers at CU Boulder鈥檚 Cooperative Institute for Research in Environmental Sciences (CIRES) and the National Oceanographic and Atmospheric Administration (NOAA), who have modeled an 鈥渋nterstate for electrons鈥� that would allow the electricity generated from renewable power sources in one area of the country to zip to another area as quickly and efficiently as autos on the highway.

Wind and solar power have long offered enormous environmental benefits compared to fossil fuels, but harnessing them on a national scale has proven challenging. The sun doesn鈥檛 shine everywhere all the time, nor does the wind blow consistently. Storing and transporting the power generated by turbines or solar panels requires expensive batteries, making it cost-prohibitive to expand wind and solar energy much beyond local use.

To tackle this problem, Christopher Clack, a CIRES physicist and mathematician, created a model that uses hour-by-hour meteorological data to identify where and when potential sun and wind energy are available over the course of a day. The sun can鈥檛 be everywhere, so the thinking goes, but it is always somewhere.

Once energy is harvested, a newly built 听nationwide high-voltage direct-current听(HDVC) transmission grid would supplement current electrical grids and transport the power quickly to wherever it鈥檚 needed most.

鈥淗our by hour, the wind and solar power combined will generate the vast majority of necessary energy, and the rest is backed up by fossil fuels,鈥� says Clack.

He also notes that what makes this system so unique is how predictive and dynamic it is in the face of ever-fickle weather. 鈥淭he model relentlessly seeks the lowest-cost energy, whatever constraints are applied,鈥� Clack explains. 鈥淎nd it always installs more renewable energy on the grid than exists today.鈥�

Under this market exchange model, weather-driven renewable power could supply most of the country鈥檚 electricity at costs similar to today鈥檚, even while slashing carbon emissions below 1990 levels.

The researchers have compared the idea to the interstate highway system, which transformed the U.S. economy in the 听1950s by enabling fast, cheap transit 听across long distances.

鈥淓isenhower said that we needed interstate highways because if you manufacture in one part of the U.S., you want to be able to bring it elsewhere,鈥� says Alexander 鈥淪andy鈥� MacDonald, the recently retired director of NOAA鈥檚 Earth System Research Laboratory. 鈥淚t turns out that electricity is the same way.鈥�

鈥淭he existing energy grid was built on a small scale, and that鈥檚 just a historical artifact,鈥� says Clack. 鈥淲hat we really need in order to integrate these renewable sources cost-effectively is to build systems on the much larger scale of weather.鈥�