A backbone defence of continuing to burn fossil fuels—that clean energy sources simply can’t satisfy the continuous heavy lifting the economy requires—is looking increasing shaky, green technology writer Jeff McMahon writes in Forbes.
“Scientists seem to be finding solutions to the variability and uncertainty of wind and solar that are relatively simple and cheap,” developments that “may be toppling one of the strongest objections to renewable energy: that wind and solar are not reliable enough to support the grid 24-7-365, so they need fossil and nuclear backup,” McMahon notes.
“I think the answer only a few years ago was maybe,” said Chris Field, director of the Carnegie Department of Global Ecology at Stanford. “Now the answer is clearly yes.”
“With a really ambitious commitment to building out the storage and load-balancing and demand-balancing components, it looks like it’s technically feasible to build an energy system with a high amount of renewables,” Field told Forbes. “It may be too expensive—and an energy system that’s got fossil with CCS (carbon capture and storage) and has some nuclear is likely to be a lot more robust and cheaper and more reliable.”
A good part of the way to a zero-emissions energy supply will be found in “better coordination between grid operators [and] the use of larger geographic areas to balance load and demand,” National Renewable Energy Laboratory researcher Michael Milligan said. Faster dispatch cycle times, “dispatching in five-minute increments, for example, instead of hourly,” would also help.
“Size matters: larger is better,” Milligan said. ”And speed matters: faster is better. And that’s true no matter how large or how small you are and how fast you’re dispatching. If you can get larger that’s going to be more efficient, and if you can get faster that’s also going to be more efficient.”
Those conditions would be favoured by the more integrated continental power grid that was endorsed earlier this year by Canadian Prime Minister Justin Trudeau, Mexico’s President Enrique Peña Nieto, and U.S. President Barack Obama.
Citing research conducted at U.C. Berkeley, McMahon adds that simulations of an electrical grid operating “with 100% penetration of water, wind, and solar power across the continental United States between 2050 and 2055” found that “no natural gas, biofuels, nuclear power, or stationary batteries [were] needed.”