Electricity is great stuff. It lights your lights, powers your computers, and can even propel your car. But for all the great things electricity can do, it is absolutely terrible at one thing—sticking around.
Once you generate electricity, you better have a use for it. Storing electricity is notoriously difficult. And it’s one of the main reasons wind and solar power haven’t caught on in a big way. When the sun dips below the horizon or the wind trails off to a whisper, customers at the end of the power lines still want their juice. Batteries seem like the obvious answer, but they are not nearly efficient nor inexpensive enough to be a comprehensive solution. Trying to save electricity for later seems like a quixotic quest, but there are more than a few people interested in trying. Solving the storage problem could help burst the already booming alternative energy industry wide open.
A consultant, a scientist, and an executive each gave their take on power storage Wednesday at the Midwest Alternative Energy Venture Forum. Their solutions ranged from revamping regulations to pairing private investors with public research centers to efficiently herding electricity across a massively upgraded grid.
Storing electricity can take on many varied and sometimes unexpected forms. Batteries are one of the oldest and most obvious of these. First invented in 1800, batteries have advanced relatively slowly. While recent advances in lithium-ion technology have helped stretch batteries to meet growing mobile needs, they still fall short for many applications. Despite this, the old cathode-anode-electrolyte approach pioneered by Alessandro Volta more than 200 years ago still has some legs—recently announced lithium-air batteries may be able to store ten times more power than previous approaches.
Jeff Chamberlain, senior account manager at Argonne National Laboratory, detailed some of the advances in battery technology, including one from his institution that would all but eliminate battery wear that results from the recharging process. Argonne and the other Department of Energy national labs are teeming this and other practical advances. Chamberlain thinks venture capitalists should mine Argonne and the other national labs for potential business ideas. The labs are excellent at developing new technologies, he said, but do not have the ability to turn those laboratory-scale discoveries into market-scale products.
Batteries are not the entire answer, though. While power companies use batteries for short-term power storage, they won’t suffice when the utility needs to store power for a long time. One solution is old but ingenious—pumped storage hydroelectric power. When supply is high and demand is low, such systems use excess electricity to pump water into a reservoir behind a hydroelectric dam. The weight of the water behind the dam is quite literally potential energy. When extra power is needed, engineers open the gates and turn on the turbines.
But such storage schemes are not widespread. Regulatory barriers are one of the reasons utilities have not built more of them, said David Walls, director of Navigant Consulting. Currently, electric companies cannot pass on the cost of energy storage systems to their customers. While the industry itself is still debating the merits of tacking another line onto the electric bill, Walls thinks the charge would help spur development.
Jay Goldman, director of transmission development of Exelon, seconded the call for clearer regulations, but added that better transmission systems could be especially beneficial for wind power. Rather than attempt to store all of the energy for later, utilities could send their power to markets where demand was higher. According to Goldman, there are 800 gigawatts of potential electricity in the winds of the Great Plaines states, an amount that dwarfs the 200 GW of demand in the eastern United States. In fact, there’s so much potential wind power that harnessing it all would overwhelm the current transmission lines that criss-cross the east. Upgrading the grid would help wind power from the Great Plaines compete in the eastern states where coal is currently king.
Energy storage is one many challenges facing alternative energy solutions, but its importance should not be overlooked. Wind energy in Texas, for example, can be so abundant at times that other companies must dump their electricity on the market at cut-rate, even negative prices when the wind is blowing strong. If the wind power producers could save some of that juice for later, they could sell their product reliably and inexpensively, reducing the need for fossil fuel power plants and driving down carbon emissions.