Here is a line from this past Sunday’s issue of Fayetteville Observer, where real-world, adult concerns about the marked inefficiency of nondispatchable energy sources, the subsidies they receive, the costs imposed on poor ratepayers by playing crony games with a state monopoly over an indispensable household necessity, the practicalities of battery storage, and other questions magically disappear if reporters pretend they don’t exist:
In an answer to [Sen. Andrew] Brock’s objections about the reliability of renewable energy, [Rep. John] Szoka said battery technology is quickly advancing to store solar-generated electricity for use on demand.
Just so! How easily that concern was handled. So battery technology is “quickly advancing” and apparently its only use would be to store solar energy for use on demand.
It’s very tidy — as long as you don’t ask such things as how much can be stored for how long at what point in the future and at what expense.
Forbes did, though, having Mark P. Mills examine those issues. Mills is CEO of Digital Power Group, a tech and investment advisory; a senior fellow with the Manhattan Institute, a faculty fellow at the school of Engineering & Applied Science at Northwestern University, and a board member of the Marshall Institute and of Notre Dame’s Reilly Center for Science, Technology & Ethics. Here’s a snippet:
The total amount of electricity stored at any given moment in all the batteries out there for all purposes is countable in minutes, not months, worth of annual demand.
Elon Musk has given us a way to illustrate the challenge to store power at grid levels. The astoundingly big $5 billion Tesla battery factory under construction in Nevada, the so-called “gigafactory,” is slated to produce more than all of the world’s existing lithium battery factories combined. For battery cognoscenti, that represents a quantity of batteries each year that can store 30 billion watt-hours of electricity. A big number. But the United States consumes about 4,000,000 billion watt-hours a year. Thus the entire annual output of the gigafactory can store about five minutes’ worth of U.S. electric demand.
Keep that in mind. The one gigafactory, at a cost of $5 billion, when it is completed, would outproduce all the world’s existing supply of lithium batteries combine.
And it could store only about five minutes’ worth of U.S. electric demand.
This says nothing about costs, or the lifespan of batteries that is counted in years not the decades needed for grid-scale power systems. It also says nothing about comparative costs of paying for availability.
Those are significant items to overlook. Continuing:
Storing electricity in expensive short-lived batteries is not a little more expensive but tens of thousands of times more expensive than storing gas in tanks or coal in piles adjacent to idle but readily available long-lived power plants.
But we are promised that better battery technology will continually emerge. Of course it will. But as has always been the case with batteries, newer tech is more expensive. There is, by the way, a market ready to pay up, big time, for better batteries.
New battery technological breakthroughs have opportunity costs. If people wish to use them to store solar energy for, well, night time, they have to bid away other potential users of the technology for other purposes. Which means they will be expensive. Continuing:
The cost of a battery in a smartphone measured in grid terms is $1000 per kilowatt-hour of capacity. This illustrates the problem. The target price that grid-scale storage needs to reach, according to the Department of Energy, is under $100 per kilowatt-hour — and for a system far more complex than the power unit in your phone. And even that is still too expensive for commodity storage by at least 10-fold.
Consider one more example of the scale challenge for storing electricity. Cushing, OK, is home to one of the nation’s preeminent, and numerous, tank farms to store oil.
In order to build a ‘tank’ farm to store kilowatt-hours equivalent to the energy stored at Cushing, we’d need a quantity of batteries equal to 40 years of production from 100 gigafactories. Electricity is hard to store.
Oil and other dispatchable technologies are their own “batteries,” if you will. Storing them in reserve stores their potential energy. It is and will for the foreseeable future be much, much, much, much cheaper to store an energy source than it is or will be to store generated electricity.
Remember about the coming, $5 billion gigafactory that would outproduce the world’s existing supply of batteries. Now imagine 99 more of them. Now take this hundredfold expanse of the world’s known battery production and calculate it out for 40 years. Presto! You have finally reached the amount of energy in the oil stored right now just in Cushing, Oklahoma.
To think that there is or will ever be a practical, feasible, cost-effective combination of solar plus battery storage to compete with a traditional dispatchable energy source is to be terribly misled.