The recent polar vortex exposed a major challenge facing any power grid based entirely on renewable energy: power storage.
Wood Mackenzie Power & Renewables issued a report in the weeks after the deep freeze that explored how a power grid based entirely on wind and solar energy would have fared as demand for electricity spiked during the polar vortex. The company’s analysts found that, as people turned on their heaters, there would have been gaps of as long as 18 hours without power in parts of the country.
That highlights the need for energy storage and new power transmission lines to fill in the gaps when the wind isn’t blowing and the sun isn’t shining, yet power demand remains high. Batteries are part of the solution, especially with battery technology improving at a breakneck pace.
But even with a forecast growth in battery storage, the analysis found that storage would have to be double the battery capacity expected to be in place by 2040 to deal with something like the polar vortex.
So a renewable energy grid will need more than just batteries. That could mean turning to alternative energy storage solutions, such as pumped hydroelectric systems, flywheels that store rotational energy, or thermal energy storage. Alternatively, nuclear power – which is contentious among environmentalists because of the issue of nuclear waste – could be an important part of the energy mix to fill in power gaps.
That said, the authors of the analysis were hopeful that these are solvable challenges. Local and state governments, along with utility companies, are already pushing towards energy storage solutions. Even with the experience of the polar vortex, experts estimate that reaching 80% renewable electricity by 2030 nationwide is a realistic goal.