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California to Optimize Electric Grid for Energy Storage

Shooting Target Bullet Holes

The United States is facing some serious issues with its electricity grid. The infrastructure was established more than a century ago, before the Internet or cellphones or a lot of renewable energy generation. It simply wasn’t equipped to handle today's electricity load.

Though the entire infrastructure represents a way of distributing electricity that's more than 100 years old, the grid has seen some updates along the way. But unfortunately, some parts of the grid haven't gotten a modern touch in more than 50 years. This leaves the electricity system vulnerable to rolling blackouts or even terrorist attacks. Many believe the grid needs a complete overall to function properly for America today.

That's why the U.S. Department of Energy is currently heading up the development of a smart grid, a computerized version of the electricity infrastructure in place today. Though it's unclear what features the new smart grid will have, the grid will need to offer more security, a solution to power outages and increased capabilities to add renewable energy to the grid. But the DOE says the project may still be another decade away from launching, leaving the country to search for more immediate solutions to power the nation. California has taken matters into its own hands.

California adopted the nation's first energy storage mandate in October 2013, requiring its utilities to expand their capacity to store energy. The ruling requires PG&E, Southern California Edison and San Diego Gas & Electric to each purchase 1,325 megawatts of energy storage capacity by 2020, 200 megawatts of which have to be purchased in the next year.

The ability to store energy has been a barrier that's hindered the growth of renewable energy in California and across the United States. You see, renewable energy isn't exactly a reliable power source because the amount of electricity it generates can vary by the day or even the hour. There's not an easy or cheap solution for storing this energy for later use. In most cases, it flows to the grid as soon as it's produced.

Utilities have to compensate for the unknown amount of green energy on the grid by over-generating power from traditional power plants.  While this ensures there is enough power available at any given time to supply the needs of consumers and prevent blackouts, the overproduction of energy, particularly from unclean resources, can be counterproductive to generating clean energy by producing more pollution instead.

This has been made even worse by California's commitment to purchase renewable resources. Beyond the clean energy that utilities purchase from wind farms, solar arrays or hydroelectric plants, the state requires utilities to purchase a set amount of distributed energy from residents each year. A recent law mandates that three of the state's largest investor-owned utilities — Sempra, Southern California Edison and PG&E — must install at least 5,200 megawatts of net metered generation, which allows customers who self-generate power to sell back any extra energy to the utility.

All electricity systems need some surplus to cover unexpected outages or generation failures, but having too much can depress the price utilities can charge for energy. Because of this, many power plants have trouble remaining profitable enough to make updates required by the federal Clean Water Act. According to the Washington Post, this could cause many of the state's power plants to shut down by 2020. Storing energy can help California utilities reserve a surplus of energy, so instead of generating too much power and depleting utility financials, the energy can be deployed whenever there's a sudden rise in consumer usage or a power outage.

Each utility is allowed to choose the type of electricity storage system that works best for its needs. There are more than 40 different energy storage technologies on the market today but most can only inject about 15 to 45 minutes of energy onto the grid. Technology continues to improve though and there are options, such as batteries, that can last for 6 to 10 hours — a duration that's long enough to cover 98 percent of power outages. But at prices upward of $750 per kilowatt hour, energy storage is not a choice that many states with struggling utilities will make.

The cost of California's energy storage solutions will fall on the shoulders of energy consumers in the state. However, the impact of how much the systems will cost ratepayers won't be known until 2014 when the procurement process begins.

Paul Batistelli's picture

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Ferdinand E. Banks's picture
Ferdinand E. Banks on Dec 25, 2013 7:00 pm GMT
Unfortunately, although these Days there are as many hustlers and liars here in Sweden as everywhere else, where energy is concerned, we don't hear very much about the smart grid. My German has become rusty, and so I can't keep up with what is going on in that country any more, but one thing is certain: in Sweden and in Germany - and almost certainly in many countries - the smart grid is a non-subject. In the case of Sweden, what is needed to obtain the elctric price we deserve is not a smarter grid but two more large nuclear facilities. And here I can mention that no matter how smarter they make the German grid, if the insane nuclear retreat proposed by Ms Merkel was a reality instead of a lie to win votes, the Germans would be in Deep trouble.
Michael Keller's picture
Michael Keller on Dec 27, 2013 7:00 pm GMT
Shades of the whiz-bang US Congress mandate to require the use cellulose derived bio-fuel. Alas, reality reared it's ugly little head; nobody has figured out a way to actually make the stuff. Ditto for the pin-heads in California and energy storage.
Jim Skeen's picture
Jim Skeen on Dec 31, 2013 7:00 pm GMT
Eliminate blackouts, outages, increase security? Does this remind anyone else of a bridge for sale?
John Buckley's picture
John Buckley on Dec 31, 2013 7:00 pm GMT
John Buckley's picture
John Buckley on Dec 31, 2013 7:00 pm GMT
In their 2002 book Thermal Energy Storage Systems and Applications, Dincer & Rosen note "Articles written around 1900 suggest that cheap and long-lived batteries are just around the corner. Unfortunately, that corner has not yet been turned ..." Another 10 years have gone by, and there have been continuing gradual improvements to MW scale electricity storage, but the most efficient way to store electricity is still to pump water up hill and let it flow back down through a hydroelectric turbine generator unit - assuming you want to build that infrastructure and withstand the environmental havoc that comes from pump-back hydro.

In the 35 years I have been in the environmental and energy field working (quite successfully) to actually improve the impact on society, MW scale energy storage technology has been a laggard. Wind and solar have improved noticeably, although I think they are still unreliable and problematic without fossil fuels to support them. Fossil fuel generation has actually "greened" the most, but they had (and continue to have) a lot of opportunity available to do so.

Still, I think it is disingenuous to characterize the grid as being not "equipped to handle today's electricity load." Today's electric grid is not in any way the same "infrastructure [that] was established more than a century ago" and the volume on the grid is actually in decline. See the annual US generation data at While I am all for investing more in our national infrastructure, including the grid, asserting that "the grid needs a complete overall [sic] to function properly" is quite over the top.

Unfortunately, I think this bandwagon of "miserable grid" press, which the author has jumped on, is being agitated by those financially invested in the non-dispatchable renewable technologies. To analogize, these generation technologies are like putting a new type of car on the road (the grid) that has no brakes, and then calling the road 'ill-equipped" because it has red lights and stop signs that the new technology can't negotiate. Let's not obfuscate this issue. The grid can be improved, but non-dispatchable generation has an inherent problem that limits its use, and rather than complain about the grid, let's fix the technology and make it more disptachable. Battery technology is still the holy grail of the power industry. I hope California is successful in spurring its development. But allowing non-dispatchable technologies to externalize the cost of the technology failings is the same as any other externality.

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