The Mind Boggling Promise of Energy Storage
December 30, 2013
A well connected individual in the EV industry told me the other day, “There are three kinds of liars. Liars, damn liars, and battery salesmen.”
Having said that, he went on to relate how, despite all the hype, false promises, and vaporware we’ve seen in recent years, it appears that serious people now believe we are on the cusp of transformative energy storage technology in wide use – tech that will make electric cars with performance comparable to gasoline, at a price point the middle class can afford, within this decade.
Welcome to the days of miracles and wonders.
We are now in a transition period where battery prices are dropping by 20-30% each year. The consequences for the automotive industry are mind boggling.
About a century ago the nascent automotive industry started out by producing electric vehicles. Even big names such as Porsche started their business on a pure-electric basis. In the hundred-year hiccup that followed we have burned billions of tons of fossil fuel, but the clean times of pure electric are returning.
The trigger to this all is simple: affordable batteries. Just as the television business was turned upside-down by the prices of flat-panel TVs in the 90’s and similarly the solar business by plummeting panel prices in the decade thereafter, we are now in a transition period where battery prices are dropping by 20-30% each year. The consequences for the automotive industry are mindboggling.
Battery prices are the main cost drivers of electric vehicles. Last year Volkswagen stated that it would be possible to manufacture a 100% electric vehicle more cheaply than a car with a combustion engine within three years.
Three years ago it was a challenge to produce an electric vehicle with a 300km range for an affordable price. Well, we have seen what happened to the stock price of Tesla Motors after the successful introduction of the Tesla-S – a 300-km range electric vehicle, which is outselling Porsche and Audi in California at the moment.
In China there is an additional market driver: megacity air pollution. The large metropolitan areas are turning into smog centers and the Chinese government has decided to invest massively and switch quickly to e-mobility. The result is the establishment of tens of new companies to produce e-bikes, e-cars, e-buses and batteries.
With the arrival of long-range affordable electric vehicles the challenges to the charging infrastructure increase proportionally. Charging power must go up, both at home and in public charging stations.
WASHINGTON — Solar power is growing so fast in California — with installations by customers increasing tenfold since 2006 — that it is turning the state’s power system upside down.
In a twist that is being closely watched by power companies around the country, California utilities will install massive banks of batteries and other devices to store the power surplus created by solar panels in the afternoon, when the sun’s rays are strong. The batteries are then to begin discharging power into California’s electric grid in the early evening, around sunset, when the solar generation of energy dies down but demand rises as millions of people get home and turn on air-conditioners, televisions and other electricity gobblers.
The new system is the opposite of an idea utilities have considered for years: Use batteries to store power at night from traditional sources, like natural gas and coal, and run them down in the peak heat of late afternoon.
“It is the reverse of the way we’ve always thought of storage,” Gregory Reed, director of the Electric Power Initiative at the University of Pittsburgh.
The relatively new idea of using batteries — which could be bundled in packs, each about the size of an 18-wheel truck trailer — to store electricity during the day and discharge it in the evening is aimed at coping with rapid changes in supply and demand. The expense of the batteries, possibly in the billions of dollars for California, has limited their use.
But booming solar power in California has changed the equation and made the California Public Utilities Commission take a different path.
At the end of October, the commission ordered the utility companies it regulates to install some form of energy storage equipment — exactly what was not specified — in the first mandate of its kind in the country. A critical purpose of the storage is to allow generators, which in California run largely on natural gas, to keep operating in the late afternoon, when the output from solar panels eliminates the need for their electricity.
With so many solar panels in California, “we may find ourselves in periods of time when we have oversupply, overgeneration,” said Clyde Loutan, senior adviser for renewables integration at the California Independent System Operator, which runs the state’s grid. That is just as destabilizing as shortage, he said.
Battery storage technologies seem to be the hot topic wherever you look in the energy industry. Germany is investing heavily into domestic storage, California has a huge mandate, and the market for peak-shifting and storing production is gaining the interest of consumers, “prosumers” and network operators alike.
In Germany, many believe that the only way to provide the amount of storage needed for a nearly fully renewable grid in the long term is through chemical means. Right now, there are a number of projects that are seeking to apply electrolysis to turn excess output from wind and solar and other generation into hydrogen and methane.
At the Fraunhofer Institute for Solar Energy Systems in Freiburg, Dr. Gunter Ebert says hydrogen and methane are the only options for large-scale “season storage.” A battery can provide some short-term storage capacity, maybe up to 50 gigawatt-hours, as can pumped hydro, but “we need a tremendous amount of long-term storage — up to 70 terawatt-hours,” according to Ebert. “That can only be done with hydrogen and methane.”
Ebert’s plan is to use caverns to store hydrogen, which can then be used for vehicles or in fuel cells. Alternatively, it can be converted into methane for use in the gas grid, or it can be used for direct heat and power generation, as shown in the following graph.
The second big technology that is being looked at is compressed air energy storage, also known as CAES. The Boston-based firm General Compression last year opened a 2-megawatt/500-megawatt-hour pilot plant in Texas last year, and its representatives have made three trips to Australia this year to talk to utilities, renewable energy developers, and government representatives about their technology.
Development officer Peter Rood says CAES would work best at the utility scale with 10 megawatts to 100 megawatts. It requires below-ground storage, either natural or man-made, and could work with storing the output of wind energy, or even as a “storage bank” for thousands of rooftop and other distributed solar systems.
Rood said that CAES will help wind energy act like a flexible gas-fired power station, providing baseload and peaking generation when needed, and storing energy produced on some windy days for use later in the week — or even the month.
Another option is pumped hydro,a technology that is being pursued by the Melbourne Energy Institute and separately by the Australian National University (ANU). Australia already has some pumped hydro (it’s a key element of the Snowy River Hydro Scheme) but the new approach looks at siting pumped hydro storage away from natural watercourses and using natural contours to situate two reservoirs at different elevations that could be used to store energy, thus negating the need to curtail output from wind farms.
Andrew Blakers of the ANU says there are numerous sites along the Eastern Seaboard, and elsewhere, that could lend themselves to pumped storage — and he is proposing that a survey should be done to identify those sites. A joint study by the engineering and consulting company Arup and the University of Melbourne Energy Institute suggested that the best approach may be pumping seawater up to coastal cliff tops, as has been done in a pilot facility in Japan (pictured below).
The irony is that pumped hydro was once built to support coal and nuclear and to ameliorate their inability to ramp up quickly to meet changes in demand. Now those energy sources will be used to absorb and manage changes in supply. The MEI/Arup investigations found the benefits included stabilizing and reducing wholesale electricity prices , increasing the spread of renewable energy, reducing the need to expand electricity transmission, and improving grid operations.
That means it would not only be able to mimic the services delivered by gas turbines, but it would also be able to compete with even combined-cycle gas turbines as gas prices head above $10/MMBTU.
“I think there will be a pretty compelling case to build wind plus storage,” he added, noting that a lot of thermal generation is aging, and a renewables-focused energy system will need storage and other ancillary services, such as frequency, that such a system could provide.
General Compression is working on a model that will provide around 20 megawatt-hours to 40 megawatt-hours of storage for each megawatt of peak power production. For a 100-megawatt wind project, the ideal would be to have a facility that could deliver between 200 megawatt-hours and 400 megawatt-hours of storage. CAES would be able to deliver this at a quarter of the price of battery technologies, according to Rood.
And the week before Christmas, the Pentagon transported 13 Nissan Leafs to a Southern California Edison charging facility in Pomona as part of a $20-million program involving dozens of vehicles at Los Angeles Air Force Base and the Naval Air Weapons Station at China Lake.
The Pentagon hopes to eventually employ the technology at bases across the country, which could jump-start mass production of the chargers and software involved.
“We’re looking to determine if we can make electric vehicles cost-competitive with conventional vehicles,” said Camron Gorguinpour, executive director of the Defense Department’s Plug-In Electric Vehicle Program. The department pays about $200 per month to lease a Nissan Leaf. Using a vehicle to store energy, he said, could generate enough revenue to offset most of that cost.
“You could pay close to nothing for the lease,” he said.