The debate over which energy storage technology will prove to be the best in the long-term is misguided, argues Chris Dalby of Oilprice.com. There will be no one-size-fits-all winner. He discusses some of the latest developments in energy storage, which show that different situations will lead to different solutions.
Many technologies have been tested in the field or been fully installed, but their real-world applications have created constant questions around a number of fixed themes: the three-points concern cost, technology, and potential environmental impact, as well as the need for specific regulation and end-of-life management.
Here, engineers have run into the dilemma of energy storage technology. It is difficult for any energy storage method, at least at the current stage of development, to produce the amounts of power and energy required at a cost-effective price. However, passing judgment on energy storage by using this equation alone is simply incorrect. After all, we do not expect renewable energy to provide a one-size-fits-all solution to help us move away from fossil fuels.
Wind farms are suitable for areas with high wind currents, such as southern Mexico, while photovoltaic (PV) plants have found more traction in sun-kissed regions like California. Even with the same type of resource, different technologies are used for different applications.
There is a lot of focus on household batteries connected with solar PV installations and batteries for electric cars. But storage has other important uses. For example, with regard to frequency regulation, batteries may actually beat the generation sources they are helping to supplant.
According to Energy Storage Report, tests at Europe’s largest commercial battery power plant, the 5MWh lithium-ion facility that WEMAG has commissioned from Younicos in Schwerin, Germany, show that batteries do better than coal plants: “Whereas coal-fired and other thermal plants typically take up to 30 seconds to adjust production up or down, and then just hit the neighbourhood of where they are supposed to be, batteries react within milliseconds.” explains Philip Hiersemenzel of Younicos.
Hence, it is highly unlikely that in the short-term, any one of the available options will turn out to be the true leader of the pack.
Last year, researchers at the University of Illinois announced the creation of a new lithium-ion battery that is “2,000 times more powerful than comparable batteries…which breaks the paradigms of energy sources.” This is a wonderful advance that, if found commercially viable, will allow for a future generation of smart phones to be charged much faster or to power single, high-energy applications such as medical equipment.
However, the accelerated output of such lithium-ion battery technology is still not able to happen on the grid-scale level that society requires. To counter this problem, some countries such as Germany have been looking at chemical energy storage as the answer for a 100 percent renewable future. This involves the use of electrolysis to create hydrogen and methane from extra energy generated by renewable plants such as wind or solar. Dr. Gunter Ebert, from the Fraunhofer Institute for Solar Energy Systems, says that these two are “the only options for large-scale storage.” In his vision, hydrogen would be used to power vehicles or fuel cells. Methane can be used in the gas grid.
Just last month, it was announced in Science magazine that researcher Michael Graetzel of Laboratory of Photonics and Interfaces at the Ecole Polytechnique in Lausanne, Switzerland, along with colleagues in Korea and Singapore, have developed a device that cheaply and efficiently converts the energy in sunlight into hydrogen. The new device is said to be remarkable “because it meets three of the four criteria needed for a practical device: high efficiency, low cost, and the use of abundant materials (so it can be used at a large scale). The next step is to meet the fourth criterion—reliability.”
The potential of producing hydrogen from solar power in an efficient and cost-effective way is mind-blowing: it would wean us off oil for good. But again, it would be presumptuous to say that these advances are resolving the energy storage debate. It looks likely that as research progresses, other equally viable forms of energy storage will occur. This will give the consumer, whether a single family or a national grid operator, the very thing that was lacking from renewable energy offerings for so long: a choice.
They will be able to determine the size of the storage that they each need and the applicability of various solutions to their needs. House owners, or a small community, might opt for a diffuse storage option with a number of small storage units across a local area. Large-scale operators, such as public transport companies, might instead prefer to rely on a centralized network comprised of several vast storage facilities.
Doomed to fail
The final problem with the current energy storage debate is the tendency to judge a method’s cost-effectiveness on the merits of available technologies alone. Much like any other scientific development, its cost-effectiveness should be calculated through links to other technologies it will be paired up with. For energy storage, these are obviously renewable energy plants. And here is where the good news comes in.
Recently, a report by Swiss bank UBS showed how the linked development of energy storage, solar power and electric vehicles is changing the economics of power generation. UBS predicts that by 2020, a return on investment for an unsubsidized purchase of an electric vehicle, coupled with a rooftop solar installation and battery storage, will drop to just six years in much of Europe. Smart distribution networks would precisely manage the usage and allocation of electricity, allowing for an electric car to be charged at night, for the sun to power a house during daylight hours and for improved batteries to store power for other residential uses.
Investment bank HSBC also produced a report recently in which it predicts advances for a range of different storage technologies. These include both small-scale and large-scale battery storage options. According to HSBC, Germany is leading this market. Afraid of being further pushed out of the market, German generators like Eon and RWE are investing heavily in storage. Eon, for example, has “snapped up an energy services company, is investing in solar PV battery storage systems for homes, has a power-to-gas pilot unit at Falkenhagen, with 2MW capacity, that can produce 360M3 of hydrogen per hour (from wind energy)”, and is investing in ten start-ups in Europe and the US active “in a range of other battery storage technologies, including a modular 5MW “multi-technology” medium voltage battery storage plant”.
Eon rightly has not made up its mind which technology to embrace in which circumstances,which shows just how the quest for “The Holy Grail of Energy Storage” is doomed to fail.
Written by Chris Dalby of Oilprice.com, edited Energy Post