What to do when there's too much power
On electric airplanes, surplus sunshine in California, and the need for creative outlets for on-supply energy consumption
Energy storage comes in many forms, some of which can be unexpected. The obvious form, of course, is the battery -- a technology that has made substantial improvements in recent years, but which still has a vast amount of progress left to make. It's becoming possible to store a lot of power when there's lots of space available (Puerto Rico, for instance, is aiming to build a gigawatt of energy storage), but while electric cars and trucks are gaining range on the ground, we still haven't quite gotten many battery-powered planes in the air (though there's reason to believe mass production of electric airplanes could yet happen within the decade).
■ Energy can obviously be stored in the biological equivalent of batteries, as food. And it can be stored as potential energy, which is part of the reason why water utilities typically fill elevated storage tanks overnight, when competing demand for both water and electricity is lower. Setting aside energy as potential chemical energy (in a form like non-perishable foods) or stored mechanical energy (as with water in an elevated tank or behind a dam) is fairly obvious and routine, once one begins to look for it.
■ But the explosive growth in renewable energy presents society with a whole new and intriguing question: How else can we time-shift the consumption of energy so that it can be used not on-demand, but rather, on-supply? The catch to renewable energy is typically that it's supplied when and where Mother Nature wishes to deliver it. We can station photovoltaic cells and wind turbines where the supplies are, on average, the most plentiful. But we can't exactly tell the winds when to blow or the sun when to shine.
■ California, notably, just had a brief incident during which renewable power generation exceeded statewide demand. And Texas is experiencing weird disparities in its power grid that, due to significant wind generation, are pushing wholesale electricity prices into negative territory.
■ Expanding the amount of electricity the country (and, indeed, the world) can generate is very much in our long-term interests as a civilization. The less we have to depend upon carbon-intensive energy in all its forms, the better. But in order to make the best use of electrical generation that occurs outside of prime consumption hours (and when storage may be either uneconomical or physically impossible), we're going to have to find new sources of demand for energy that can be switched on and off when the power is available. One of those outlets for demand could be found in on-demand recycling of materials like steel that require lots of power.
■ Such a recycling scheme is only one of many uses we'll need to identify, if what we want to do is optimize our usage when the supply is plentiful. But the better we do at finding economically productive outlets for off-peak energy supply, the better the rationale will be for expanding the supply of renewable energy. And the better we achieve a market-friendly supply, the better we'll be able to align the interests of markets with the interests of maintaining a healthy environment for human beings in the future.