June 20, 2017
California, U.S.

Study: a fully renewable energy grid is too costly for now

By Michael Lipkin | KPBS | June 19, 2017 | www.kpbs.org

Solar panels, wind farms and hydropower facilities contributed 80 percent of the energy on the largest portion of California’s power grid on May 13, a record for renewable energy sources. But can wind, solar and hydroelectric power sustain an entire electric grid full-time?

The debate over when a fully-renewable energy grid will be possible continues with a study published Monday in the Proceedings of the National Academy of Sciences by researchers representing more than a dozen schools and research institutions in the U.S. and Sweden including UC San Diego.

One of the key problems of a totally reliable grid is keeping up with demand, even if winds slow or clouds cover solar panels. And storing electricity in batteries for those lulls can be expensive. A study two years ago co-authored by Stanford University professor Mark Z. Jacobson argued a 100 percent renewable grid is possible by 2050, with new ways of storing energy in soil or water allowing for a low-cost conversion. The paper was named one of the best of the year.

Now researchers, including David Victor, co-director of UC San Diego’s Laboratory for International Law and Regulation at UC San Diego argue Jacobson ignored important costs.

“Policy makers should treat with caution any visions of a rapid, reliable, and low-cost transition to entire energy systems that relies almost exclusively on wind, solar, and hydroelectric power,” Victor and others wrote.

The new research also notes that Jacobson assumed nearly every building in the country would have an underground thermal energy storage system but didn’t account for the costs to install pipes, distribution lines and other infrastructure.

According to Victor, the technology theoretically exists to build a completely renewable energy grid, but at the moment only “unlimited resources” could guarantee a system that could meet any possible energy load.

These new findings come a month after Sempra Energy executive Patrick Lee said the technology existed for a 100 percent renewable grid and that building one was now an economic question. Sempra later said the comments, delivered at an energy conference, were “aspirational.”


URL to article:  https://www.wind-watch.org/news/2017/06/20/study-a-fully-renewable-energy-grid-is-too-costly-for-now/