Profile Network Activity Comments Articles Blog Bookmarks Contact

Energy Storage Crucial Step for Renewable Electricity

By Pete Singer
November 23, 2010 | 16 Comments

Do you like this blog post?

Bookmark

U.S. policymakers must focus more closely on developing new energy storage technologies as they consider a national renewable electricity standard, according to one of the principal recommendations in a newly released report, Integrating Renewable Electricity on the Grid, by the American Physical Society’s Panel on Public Affairs (POPA).

The report notes that as renewable generation grows it will ultimately overwhelm the ability of conventional resources to compensate renewable variability, and require the capture of electricity generated by wind, solar and other renewables for later use. Transmission level energy storage options include pumped hydroelectric, compressed air electric storage, and flywheels. Distribution level options include: conventional batteries, electrochemical flow batteries, and superconducting magnetic energy storage (SMES). Batteries also might be integrated with individual or small clusters of wind turbines and solar panels in generation farms to mitigate fluctuations and power quality issues.

According to APS, cnergy storage for grid applications presently lacks sufficient regulatory history. Energy storage on a utility-scale basis is very uncommon and, except for pumped hydroelectric storage, is relegated to pilot projects or site-specific projects. Some states such as New York categorize storage as “generation,” and hence forbid transmission utilities from owning it. In addition, utilities do not know how investment in energy storage technologies will be treated, how costs will be recovered, or whether energy storage technologies will be allowed in a particular regulatory environment.

Another challenge facing the grid involves the long-distance transmission of renewable electricity from places that receive a lot of wind and sun to those that do not. “We need to move faster to have storage ready to accommodate, for example, 20 percent of renewable electricity on the grid by 2020,” said George Crabtree, co-chairman of the POPA study panel and a senior scientist at Argonne National Laboratory. “And, by devoting the necessary resources to the problem, I am confident that we can solve it.”

The report addresses variability and transmission issues by urging the U.S. Department of Energy (DOE) to increase research on materials to develop energy storage devices and by encouraging the DOE to focus on long-distance superconducting direct current cables to bring renewable electricity to load centers, lessening the chance that power will be disrupted. The report also calls for examining renewable electricity in light of a unified grid instead of one that is fragmented and improving the accuracy of weather forecasts to allow for better integration of renewable electricity on the grid.

The APS report says the DoE should develop an overall strategy for energy storage in grid-level applications that provides guidance to regulators to recognize the value that energy storage brings to both transmission and generation services on the grid. The DoE should also conduct a review of the technological potential for a range of battery chemistries, including those it supported during the 1980s and 1990s, with a view toward possible applications to grid energy and storage. Another recommendation is that the DoE should increase its research and development in basic electrochemistry to identify materials and electrochemical mechanisms that have the highest potential use in grid-level energy storage devices.

The American Physical Society is the leading physics organization, representing 48,000 members, including physicists in academia, national laboratories, and industry in the United States and internationally. APS has offices in College Park, MD (Headquarters), Ridge, NY, and Washington, DC.

Solar Energy

The information and views expressed in this blog post are solely those of the author and not necessarily those of RenewableEnergyWorld.com or the companies that advertise on this Web site and other publications. This blog was posted directly by the author and was not reviewed for accuracy, spelling or grammar.

16 Reader Comments

Comment
1 of 16

mmarton

November 23, 2010

We need to see more mention of distributed thermal energy storage. It's simple, cost effective and will produce significant grid efficiency.

Comment
2 of 16

talha15

November 24, 2010

This is a very informative article..I have made my effort in explaing how the Current Energy

Order is Changing and Changing Fast..The link is given below..

http://authorshive.com/2010/11/24/current-energy-order-is-changing-fast/

Comment
3 of 16

sol-shapiro-138588

November 24, 2010

The "hand wringing" about the need for storage ignores the ability of csp (solar thermal) electric generation ability to store thermal energy before generation; and integrate with natural gas when too many cloudy days in a row outrun storage. The pv and wind people in attempting to continue to grow their resources do need "post generation" storage and it's not bad to look a these; but it is just POSSIBLE as the current generation of csp is built out and costs drop that csp will become the "800 pound gorilla" of electric generation.

Comment
4 of 16

JimW

November 24, 2010

One type of storage I dont notice in your list is GreenGas.cc The fuel is the storage. Since it is now working, it should not be overlooked.

Comment
5 of 16

OFFGRIDSOLAR

November 24, 2010

When It comes to energy storage and solar modules. This has been around since 1968. The first application was for aids to navigation. The only true way to have a gen and co gen using solar PV is to use batteries. Solar PV can also be used in production of hydrogen. Again batteries. The Greeks invented batteries 5,000 years ago. In all off grid solar photovoltic systems you use batteries. Batteries are very reliable. Your cell phone and car needs a battery to operate. This will drive the cost of generating electric power to grid prices. But the best feature with a Off Grid Solar system you will have real energy independence and a sustainable future.

Comment
6 of 16

matt-karber-75150

November 24, 2010

As Beacon Power has discovered, the grid needs energy storage even now, before renewables are a significant percentage of energy production. This situation will only become more pronounced with time. When all factors are considered, the best solution is likely the combination of an electrolyzer, hydrogen(H2) tank, and fuel cell. Excess production can be used to generate H2, which is stored until needed during peak demand periods. Fuel cells and tanks are long-lasting, and should not need replacing nearly as frequently as batteries. We have yet to see how flywheels will perform in the long term in a utility environment. Fuel cells also need little maintenance, since they have no moving parts. They also have much better power density (kW per cubic foot) than batteries. This is likely the greenest and most efficient storage solution.

Comment
7 of 16

hoppe-w

November 26, 2010

The largest capacity for regulation of variable renewable energy production is intelligent control of consumption via variable price levels.

Comment
8 of 16

ericmair

November 26, 2010

Pumped hydro storage is the answer except that you need a mountain and that means environmental issues.
Now there is Gravity Power - pumped storage almost wherever you want it.
http://www.launchpnt.com/portfolio/grid-scale-electricity-storage.html

Comment
9 of 16

dennis-houghton-41194

November 26, 2010

Ericmair is correct that pumped hydro storage is the answer and the link he provided details another elegant solution. However it may be simpler and cheaper to develop pumped hydro storage at existing run-of-the-river dams typical on the Columbia and Snake rivers in the Pacific NW. You do not need a mountain. The best solar PV example might be at the Hoover dam in the SW but huge water use issues complicate the concept.

The John Day Dam on the Columbia has rated generating capacity of about 2200 MW and a large impoundment reservoir. Water in the reservoir is used for irrigation, freight transport, fish and wildlife, recreation as well as power generation. Water used for irrigation and other purposes is lost to the generating system. Fish ladder and barge lock operation bypass large volumes of water around the turbines. What if a solar PV system water pumping system was designed around the specific target of recycling the energy in the Fish ladder bypass water from below the dam back to the reservoir.

Battery charging systems sometimes have a diversionary load when full charging current is not needed. The diversionary load often has value and is not just wasted heat. About 1000HP / MW solar could be effectively used at John Day dam with @250 of head for @10000GPM flowrate. BPA already integrates extensive wind contribution into its total power offering. They could easily integrate solar PV if they had control of a balancing diversionary load.

Build utility scale solar PV next to existing hydroelectric facilities, there usually is plenty of space and the grid connection is close. Use the water as the energy storage/value transfer medium. Manage the water through diversionary pumps.

Comment
10 of 16

thomas-mayrand-14505

November 26, 2010

If you think about it, we all have energy stored in our driveway. A battery that can start an engine that which has all kinds of power and capabilities. But one battery can make all the difference. So, perhaps two or more batteries at each residence could add up to significant storage, each powered by their own or shared, local PV setup.
Then they can use the power for themselves and lessen the burden on the grid and/or tie into the grid, if they choose to, in order to supply power to those who need it.
It shouldn't take to much math to figure out how much power could be stored in one small neighborhood.

Comment
11 of 16

mary-saunders-73470

November 26, 2010

Floating solar on water storage can allow you power to survey the water for temperature, ph, etc., in addition to moving the water around if desired. Floating it also reduces evaporation if water conservation is a goal. It may also allow cooling the PV to optimum temperatures for peak efficiencies. If underground aquifers are available, they can store solar thermal quite well (see Heat from the Street). The Pacific NW is not working to potential in this regard. With SolarWorld right here, we could do better quickly if the will to do so would materialize beyond the fog of doing things in grandfathered, and unfunded-mandate ways. M.D. after M.D. and other experts and groups testify against concrete covered water storage over and over in Portland, to no avail. The no-bid contract, do-it-before-a-holiday boys are up to the usual top-down, crony-empowerment tricks.

At least Cleanwater Services of Tualatin is more modern, if only they would make a community hot-tub with the methane they are flaring. Too expensive to use it, they say.

Comment
12 of 16

jerry-cheesman-41023

November 27, 2010

Some specific storage options available, but seldom discussed, might be;
1) the use of excess-off-peak wind energy capacity, to store hydrogen in one tower section and oxygen within another tower section, then using it in a fuel cell type technology to produce the equivelent electricity during peak demand periods thus improving grid stability, where the hydrogen can be stored as a solid in chemical combination with another element, to be catalytically released to re-power an undersized fuel cell, by the effect of the rate of release of waste heat frum the fuel cell into the chemical stornage area.
2) near term efforts to identify wind farms which have good records of infrastructure and high levels of solar contribution/sq. meter, and where the appropriate land is available to add solar electric capacity to smooth out the match between supply and load from a renewables standpoint and from a load standpoint. A good example would be the wind farms here in Solano County, California, which could be complimented both on and off-site by solar farms. In this case we are speakinig about as much as 850 MW solar generating capacity. Currently, PG&E, and SMUD, are in the process of installing 250 MW and an unknown amount respectively. This would act like storage at a reduced cost due to the ability of solar to more closely match the peak demand period. This has the effect of more efficiently providing peak demand from current solar than from storage.

Comment
13 of 16

PeteSinger

November 28, 2010

Thanks for all the comments. I've started a regular blog on energy storage at www.energystoragetrends.com.

Comment
14 of 16

ryanhaggerty

November 29, 2010

This is a problem that will have to be addressed very soon. In our state, wind generation hit an all time high meaning there was more supply than demand so the wind turbine operators were instructed to slash output as to not overload the grid. What a shame to have all of those high tech high dollar turbines doing what they do best only to have to cut production when they were working at their peek.
The article can be found here: http://www.oregonlive.com/business/index.ssf/2010/07/too_much_of_a_good_thing_growt.html

Comment
15 of 16

davidkusel

December 13, 2010

The storage system already exists. Its low tec and its cheap.
Big Dams. which were built ages ago & whose cost has already been written off.

Their turbines can be turned off and on at will.
The "saved" water represents stored energy.

If the turbines are built to run backwards as well.....which is simple technology, the dams can be used to store "excess" w power from any source, when theres too much energy going into the grid...... both thermal and nuclear power stations "prefer" to run on full power, but demand is highly variable.

Spain now covers 20% of its electricity needs with wind power, and some days this figure can go up to 40% !
All this with no special new storage capacity or grid modification.

The utilities are not so happy because they are no longer running their new combined cycle gas burning stations all day every day.

Comment
16 of 16

Angus

December 21, 2010

I think floating offshore wind/wave and tidal current developments could store excess energy onboard large ships in the form of compressed air and transport it to energy hungry ports of call such as New York or LA or Miami during peak consumption times. Onboard generators would then convert the energy to elctricity without the complications of long grid transmissions and sail again to refill on compressed air. Since these ships would be huge and use only compressed air to sail, they would be pretty much carbon nuetral after construction is taken into account.

Add Your Comment

Registered users, please make sure to Sign-In. We and others want to know your ideas and opinions. If you are not yet Registered -- it's quick and easy. Just click below.
Thanks!