Thursday, December 31, 2009
Tuesday, October 27, 2009
Tuesday, September 29, 2009
The recent New York Times article, "Companies Race to Develop Utility-Scale Power Storage" pointed up the problems and potential for confusion. "Power storage" technologies listed included the Beacon flywheel, the NGK molton sodium-sulfur battery, the A123 lithim ion battery, and compressed air (again!). Quoting a report by GTM Research, this article made a very insightful distinction between "power oriented" technologies, used mainly to regulate short-term changes to grid frequency, and "energy oriented" storage -- in which energy use is shifted to other times of the day. However, the author could have done a better job applying this distinction and pointing out the difference in cost.
For example, the article discussed the $69 million Beacon project in New York, where they will install, "...hundreds of "flywheels" to store 20 megawatts of electricity, enough to power 200 homes for a day." In reality, the flywheel is designed to store only 15 minutes of power and falls into the "power oriented" category above. Its total energy storage will only be 5 MW hrs, about enough to power 40 homes for a day, although it will never be used for that purpose.
Also, the article reported on the $25 million requested by Southern California Edison for an A123 "32-megawatt-hour battery" - but is it really 32 MW hrs? I pose the question because the system will be designed as an 8 MW battery with 4 hours of storage (32 MW hr), but the application is at a wind farm, where multiple cycling is needed to firm wind - a "power oriented" application. Lithium ion batteries are good for about 500 - 600 complete charge and discharge cycles. If it is used in an "energy oriented" application, shifting wind power at night to the day, then it will only last about 2 years. However, in a "power" application, where the battery is barely discharged, it will last for many thousands of cycles. In fact, this is how it is currently applied. In this case it would be operated like an 8 MW flywheel, with usable energy storage of only about 2 MW hrs.
So how do you value these installations? If we value the flywheel and the li-ion systems by the MW hr, then their cost is $13.8 million and $12.5 million respectively. However, if all we care about is their power capacity, then the cost is $3.45 million and $3.125 per MW. (The NGK battery is the only energy oriented technology mentioned in the article, but no cost information was provided.)
By contrast, a VRB-ESS (vanadium redox flow battery - energy storage system) will provide both energy and power, with nearly unlimited cycles, full or partial, for about the same cost per MW of the flywheel or li-ion battery. However, the VRB-ESS will also include 4 - 8 hours of storage, dropping the cost per MW hr to a fraction of the cost for a "power oriented" system.
For example, a 5 MW system with 6 hours of storage would cost about $18 million, with all costs included - a complete turn-key system. That would provide 30 MW hrs of energy at a cost of about $600 thousand per MW hr. The cost of power is only $3.6 million per MW.
Although not directly relevant to the discussion, it's good to know that the VRB-ESS will last 10 years before needing refurbishment. This consists of replacing the PEM (proton exchange membrane) at a cost of about $3 million. The system is then good for another 10 years!
Bottom-line? - It's important to understand the application, whether energy, power or both, and then determine the cost per energy (MW) and/or the cost for power (MW hr), when evaluating the technology.
Friday, September 18, 2009
1. How do you define utility scale energy storage?
I would suggest looking at several common sense issues to get a handle on what is utility scale or grid connected energy storage (GCES).
First, we should define energy storage as "electrical" energy storage. That means electrical energy storage in and electrical storage out. For utility or grid applications, we need to store electrical energy for use when needed; meaning excess electrical energy is shifted to a time when electric energy is scarce. This excludes some types of valuable energy storage, like thermal energy storage, but it clarifies what we are doing.
Thermal storage is a good thing and useful, but it cannot be used to produce electrical power for the grid, so it should be excluded from our consideration. This is not to single out thermal energy, but to illustrate the need to focus on electric energy storage. The distinctive of utility or grid energy storage should be the storage of electricity. Storing electricity energy for use as some other type of useful energy does not provide the grid with the electric energy when needed. It is load only. Electric energy storage should be a two way street, not a one way street.
Logically, this also excludes electric energy generators. Again, this is an example of taking a different type of energy and converting it to electricity. Unless we define GCES as electricity in and electricity out, then a coal plant could be considered as GCES since it stores energy in the form of coal and provides energy as needed. If we do not specify electric in - electric out, then our discussion will be so broad as to be meaningless.
And, if we are careful to define GCES as electric in - electric out, then this will also exclude fuel driven compressed air energy storage systems. Such CAES systems are more clearly understood as highly efficient natural gas generators. Electric energy is used to run compressors. The compressed air is used to run natural gas generators more efficiently. Burning natural gas to produce electricity is not electric energy storage. It may be very desirable in some ways, but it should not be in the same box as other technologies that store electricity. If we include fuel driven technologies, then, again, our discussion becomes meaningless.
The second concept to address is the "storage" issue. The common sense expectation is that we are focused on storing and delivering useful amounts of electrical energy.
For example, there is a difference between delivering energy and providing power quality services. Various devices and technologies can store and deliver short bursts or pulses of power to balance short term variations in power quality. Utilities and energy users install various devices for this purpose. But their use is for power quality, not energy.
Similarly, the CAISO operates a market for frequency regulation that is considered a "capacity" market, as distinguished from their "energy" markets. Some ISO's are developing opportunities for Limited Energy Storage Resources (LESRs) to provide capacity - not energy - services, because they recognize the benefit from the quick response of such technologies. However, these systems are, by definition, limited in their energy and are not valued for their volume but for their capacity. Although valuable, they are not useful for energy delivery. At a minimum, a GCES facility should be able to store and deliver electric energy in hours, not minutes. We refer to the technical parameters used by the California Public Utilities Commission in their definition of advanced energy storage for the Self Generation Incentive Program. (Decision 08-11-044 November 21, 2008, page 12, “Ability to be discharged for at least four hours of its rated capacity to fully capture peak load reductions in most utility service territories (required AES duration of discharge will depend on each customer’s specific load shape, and the duration of its peak demand during peak utility periods).”)
LESRs should be in their own separate category for the valuable power quality benefits they provide to the grid, but they should be excluded from the GCES discussion because they cannot deliver energy in useful quantity.
Friday, August 28, 2009
- First, the $25 million requested is only for "initial analysis and design". The anticipated cost for the project will be $368 million. And that's before we see the cost over runs, delays and unexpected problems a huge project like this will invariably incur.
- Then the utility will have to explain why they want to take "clean" wind energy and make it "dirty". Because, you see, the compressed air will be used for natural gas turbines! The argument is that the compressed air will make the natural gas turbines run more efficiently, requiring less natural gas - which is great if you're trying to make your natural gas turbines more efficient. But we thought the point of wind energy was to produce clean and renewable power - not more fossil fueled power.
- And how much energy will we lose in this process? We create a certain amount of energy with wind and then burn it away by compressing it and burning natural gas. What is the net delivered energy when all of this is finished? I've seen reports of as little as 54%. So we take wind energy, throw away 40% or more, increase the price volatility through the natural gas market, and add emissions and GHGs. Why is this a good idea?
Thursday, August 27, 2009
We are well aware of the DOE grant program because we are involved in several applications for the VRB-ESS. We'll provide more information as we have developments we can share.
Here are the issues and questions I have with the story:
- First, I cannot find a press release from SCE. The story appears to based on an interview with Paul De Martini, Southern California Edison's vice president of advanced technologies. This makes it a bit difficult to get more detail or clarification. We'll ask Mr. De Martini for clarification.
- Next, the story says the grant is for 32 megawatt hours of storage. Since the current A123 grid systems in place are for grid stabilization, with only about 15 minutes of storage, Edison would need to install 128 MW of capacity to get 32 hours of energy. That would make it a huge, unheard of capacity battery, but with very short term storage. So, I'm not sure what the application would be for wind energy. 4:1 capacity to energy storage is normally conceived for frequency regulation, which is the current application for A123. That type of application can be anywhere on the grid - there is no need to place it at a wind farm. We normally think of storage for wind for the purpose of shifting generation from night time production to the day - something you can't do with 15 min. of storage.
- If the project is 32 MWHrs of storage, then it isn't the biggest project by a long shot. The 238 MWHr system by NGK in Japan wins that contest with their 34 MW by 7 hours of storage system. Sure, they can only use half the capacity at a time to avoid overcharging, but the total is still greater than the Edison project - if the story is correct.
- The ARRA grant is a matching grant, so we assume Edison will need to seek approval from the California Public Utilities Commission for an additional $25 million, or more, for a total cost of $50 million. That's $1,500 per kilowatt hour! - pretty darn expensive. For comparison, the flow batteries and NGK are between $500 and $700. However, on a capacity basis, at 128 MW, it's only $390 per kW.
- If the story meant to state a 32 MW capacity, then the economics make no sense.
Wednesday, August 5, 2009
The Smart Grid Demonstration Grant is looking for several different types of demonstrations. The VRB-ESS is a good candidate for each category except one that is specifically set aside for compressed air energy storage. Grants are running from a couple million dollars for 1-3 MW installations to $25 million for 8-15 MW.
Here is the current breakdown of incentives for the VRB-ESS. We believe that the VRB-ESS specifically qualifies for these incentives in California - other energy storage technologies may not qualify.
- ARRA - Under the current grant opportunity, the Department of Energy will fund 50% of an eligible project.
- SGIP - the California Self Generation Incentive Program will provide a rebate of $2 Watt ($2 million per MW) for the VRB-ESS in association with on-site fuel cells or wind turbines. We believe the VRB-ESS will also qualify for an additional 20% ($2.40 per Watt) under a specific provision for California suppliers.
- ITC - The Investment Tax Credit cash grant is equal to 30% of a project cost when integrated with other renewable energy projects. There are many conditions to this grant, but it's actually very liberal for the VRB-ESS. It will apply to VRB-ESS retrofits to existing cogeneration, fuel cells, biomass, hydro, wind, solar, etc. installations.
Friday, July 17, 2009
Sunday, July 12, 2009
I use the analogy with energy storage and the VRB-ESS. Different players see the VRB energy storage system from their limited perspectives and they tend to have limited applications. Is the VRB-ESS a peak shifting resource, distributed energy resource, demand response, intermittent renewable energy integration, capital deferral of distribution / transmission assets, power quality, emergency power, on-site power, capacity, ancillary services - frequency regulation, and so on? The answer is yes, all of these, and we should "grasp" the greater value of multiple benefits.
Now Pike Research has a slightly different analogy regarding the market for energy storage, "The energy storage market is like a charging elephant: even if you can’t see what it looks like, you know it’s going to be big." They have a report out that projects a 10 fold increase in the "stationary utility" market from 2008 to 2018 to $4.1 billion. Most market projections for energy storage include vehicles and small applications - like laptop computers - so this is unique and interesting. Energy storage in general, and the flexible and powerful VRB-ESS in particular, have an important and profitable future. More information can be found at their website: http://www.pikeresearch.com/
Thursday, July 9, 2009
"An example of Florida's expertise in energy storage is a demonstration project conducted by University of South Florida and partner Progress Energy Florida which combines renewable distributed energy generation and an advanced battery system to supply renewable energy generated in off-peak hours during peak power demand hours. One of the prototypes of the Sustainable Electric Energy Delivery System (SEEDS) is used on campus, the other at a nearby park to power lights at night."
However, this announcement was posted today, including this audio. Although the VRB-ESS wasn't mentioned by name, they discussed the battery system and the vanadium technology.
Wednesday, July 1, 2009
Tuesday, June 30, 2009
Shared via AddThis
Tuesday, June 23, 2009
Wednesday, June 17, 2009
While much of the discussion about the the smart grid has focused on cool demand side gadgets to control thermostats, air conditioning and refrigerators - and the software and incentives (or forced compliance) to control them, the most effective "smart" appliance is an energy storage system. Energy storage on a distribution grid allows for the most efficient use of renewable energy - like PV systems on residences - and peak demand that occurs from air conditioning (and future hybrid plug-in cars) without intrusive monitoring of residential power use. What a concept - one robust and dispatchable grid connected battery - like the VRB-ESS - instead of multitudes of residential controllers, software and regulations.
Duke Energy plans to demonstrate such a common sense approach. Their system will utilize an advanced flow battery to balance PV, shift generation to cover peak, and provide power quality. Residential customers will be given the option to change power consumption by providing them with information and incentives - not by forcing remotely monitored / controlled motion sensors (to turn lights and power off and on) and thermostats on customers.
The advanced energy storage system (battery) allows Duke to work cooperatively with their customers without forcing compliance or intruding into their privacy. Customers can chose to respond to price signals or other data provided by Duke. However, the battery fills in any gaps and provides a truly "smart" addition to the grid.
Tuesday, June 9, 2009
"In an effort to increase infrastructure supporting renewable fuels, the STORAGE Act provides investment tax credits for energy storage facilities and equipment that temporarily store energy for delivery or use at a later time. Currently tax incentives are only available for the generation of renewable energy, but output from wind, solar, and wave and tidal energy projects literally rises and falls with natural conditions. Storage technologies can help harness the output of renewable energy sources and allow them to be used when they are most needed. The bill encourages innovation by providing tax credits for a broad range of storage technologies, from water reservoirs to flywheels to hydrogen production to batteries when connected to the nation’s electricity transmission and distribution system and when installed in homes, businesses, and factories."
Although mentioning flywheels and hydrogen production, the language of the bill seems to be more oriented to advanced batteries like the VRB-ESS.
For example, the definition of ‘qualified energy storage property’ includes a minimum requirement to store at least 2 megawatt hours of energy, and output 500 kilowatts of electricity for 4 hours. On the face of it, this 4:1 storage v. capacity ratio would seem to rule out a flywheel that only has 15 minutes of storage. However, a flywheel system could provide 4 hours of electricity at 500 kW if the storage was oversized to 8 MWHrs. The conceptual grid-connected flywheel system, like that of Beacon Power, as well as the lithium ion systems, like Altairnano (see anuual shareholders presentation), are planned to provide short pulses of energy for grid stability, not sustained electricity delivery of more than 4 hours. So, a large flywheel/li-ion system could qualify, but it would seem to go against the conceptual definition in the bill. Looks like a loophole that Senator Wyden may want to tighten.
Also, the bill requires the energy storage to store and deliver electricity. For hydrogen production to qualify, a system would have to be designed to use electricity to generate hydrogen - say through electrolysis of water - and then convert the hydrogen to electricity - perhaps through a fuel cell. The problem is that this wastes a tremendous amount of energy. Taking 100 units of electricity through this cycle only returns about 20 - 30 units of delivered power. By comparison, storing electricity in the VRB-ESS is about 75% efficient. This may be another area for Senator Wyden to be more specific. Does he want to incentivize grossly inefficient electric storage systems?
We'll continue to follow this bill and comment.
Friday, May 29, 2009
Much interest was engendered by the smart grid stimulus money. According to the ESA, there were over 40 presentations from 10 panels.
Although we did not attend, we had our sources. We learned that the VRB-ESS is still well perceived.
"In general, people seem keen on the VRB technology and happy that Prudent has chosen to pick up where VRB left off in developing the technology. While the competitive environment is getting more well-populated, flow batteries in general and the VRB technology in particular are still noted in many of the presentations. Consensus seems to be that they definitely have a part to play in the energy storage industry.
NGK's molten sodium sulfur NAS battery is well accepted in Japan. According to one pr
esentation, they have over 270 MW located at 190 sites in Japan. In fact, they are "sold out" through 2010. (Which means, apparently, that it will not be possible to install a large energy storage facility with the NAS battery under the smart grid stimulus grants?)
My comment - I wonder how a large installation of NAS would be accepted in the USA? I personally think the Japanese are much less sensitive to such things. I saw a peaker plant go down in flames from neighborhood activism in S. Orange County, California. This natural gas plant was nowhere near any houses, out of sight, and no one would ever know when it was running. However, a few activists were able to shut down the "smokestack power plant". I have to believe there would be some real reaction to a molten sodium/sulfur plant of any size near a neighborhood, even though NGK has engineered substantial safeguards into the system.
One interesting note is that there was a complete failure of the NGK system in New York this past year, requiring that the entire storage system be replaced. Apparently the NaS system cannot be completely discharged without suffering irreparable damage" I didn't find any news on the internet about the failure - anyone have a reference?
I also received this report on the NGK system in New York: "
Lithium batteries of various types received substantial attention - and why not, they're getting all the money! But they aren't ready et for long term storage - most applications are for quick response, short term storage - like flywheels.
The VRB-ESS still looks good for large, grid connected storage.
Thursday, May 21, 2009
I see the same cycle being repeated with energy storage. Now that energy storage is seen as crucial to integrating renewable energy, the press and media seem to be looking for any new and exciting concept or R&D that could result in a story, without really evaluating the potential for practical success or application to our need for storage.
For example, I have seen articles recently about storage from "bug farts", "air fueled batteries", and a new flow battery that is safer and more reliable, costs less, and would be a good fit for solar and wind farms- but they won't talk about how it works.
I can't say that all or any of these technologies will be the energy storage equivalent of vaporware, and some seem to have some pretty serious and knowledgeable people behind them. However, it seems easy to get a lot of press on a concept or technology that is years away from any practical application.
We should continue our R&D and enjoy discussing new and creative energy storage ideas - but we also need to be realistic about our need for energy storage, and our need to begin deploying those technologies that are available now. Vaporware isn't going to solve our problems!
First, some background - the VRB-ESS is the vanadium redox flow battery (VRB) energy storage system (ESS) by Prudent Energy. More information on the technology is available at our website, www.Utility-Savings.com. My comments on this blog are my own and do not necessarily represent those of Prudent Energy or anyone else connected with the company.
The VRB technology is decades old and installed around the world in various sizes from 5 kW to 6 megawatts. It's ready for mass deployment for smart grid and wind/solar energy integration. We are looking for opportunities, such as provided by the smart grid stimulus funding, to deploy large installations and bring the cost down through economies of scale. Just like photovoltaic technology (PV), the cost for this technology has been significant, limiting installation to demonstrations and niche applications. However, the deployment of intermittent renewables, like solar and wind, is focusing attention on the need for massive energy storage, and incentives are being created to reduce installation costs and build the pipeline. Thus, like PV, greater deployment, due to these financial incentives, will result in cost reduction through economies of scale, resulting in even greater penetration and benefit to the grid.
Utility Savings & Refund, LLC (US&R) is my company and we are a sales affiliate for the system. We saw the possibilities for this amazing technology back in 2006, and we've been promoting it ever since. I'll be discussing some of the potential applications and benefits in later posts. However, my plan for this blog is to comment on current developments in energy storage, not to use the blog as a long infomercial for the VRB-ESS. That being said, please keep in mind that I will feel free to comment from the perspective of one that is most familiar with one specific and practical energy storage solution.