As nuclear power plants close, states need to bet big on energy storage Skeptical Science 9 August 2016 by dana1981 Eric Daniel Fournier, Post Doctoral Researcher, Spatial Informatics, University of California, Los Angeles and Alex Ricklefs, Research Analyst in Sustainable Communities, University of California, Los Angeles This article was originally published on The Conversation . Read the original article.
“……due to negative opinion and costly renovations, we are now observing a trend whereby long-running nuclear power plants are shutting down and very few new plants are being scheduled for construction in the United States.
Utilities are moving toward renewable electricity generation, such as solar and wind, partially in response to market forces and partially in response to new regulations that require utilities to reduce greenhouse gas emissions. In California, in particular, the shift toward renewable energy for market and environmental reasons, along with the public’s negative perception of nuclear energy, has caused utilities to abandon nuclear power.
While opponents can view the shutdown of nuclear power plants as a health and environmental success, closing nuclear plants intensifies the challenges faced by utilities to meet electricity consumption demand while simultaneously reducing their carbon footprint. PG&E, for example, has pledged to increase renewable energy sources and energy efficiency efforts, but this alone will not help them supply their customers with electricity around the clock. What can be used to fill the sizable gap left by Diablo Canyon’s closing?
Solar and wind energy sources are desirable as they produce carbon-free electricity without producing toxic and dangerous waste byproducts. However, they also suffer from the drawback of being able to produce electricity only intermittently throughout the day. Solar energy can be utilized only when the sun is out, and wind speeds vary unpredictably.
In order to meet customer electricity demand at all hours, energy storage technologies, alongside more renewable sources and increased energy efficiency, will be needed.
Enter energy storage
Energy storage has long been touted as the panacea for integrating renewable energy into the grid at large scale. Replacing the power generation left by Diablo Canyon’s closing will require expansive additions to wind and solar. However, more renewable energy generation will require more storage.
There are many different energy storage technologies currently available or in the process of commercialization, but each falls into one of four basic categories: chemical storage as in batteries, kinetic storage such as flywheels, thermal storage and magnetic storage.
The different technologies within each of these category can be characterized and compared in terms of their:
- power rating: how much electrical current produced
- energy capacity: how much energy can be stored or discharged, and
- response time: the minimum amount of time needed to deliver energy. [excellent graphs provided here on original]
The key challenge that utilities are now faced with is how to integrate energy storage technologies for specific power delivery applications at specific locations.
This challenge is further complicated by the electric power transmission system and consumer behaviors that have evolved based on a energy supply system dominated by fossil fuels. Additionally, storage technologies are expensive and still developing, which makes fossil fuel generators look more economically beneficial in the short term.
Implementing storage technologies
Currently in California, energy storage is effectively provided by fossil fuel power plants. These natural gas and coal-powered plants provide steady “baseload” power and can ramp up generation to meet peaks in demand, which generally happen in the afternoon and early evening.
A single energy storage device cannot directly replace the capacity potential of these fossil fuel sources, which can generate high rates of power as long as needed.
The inability to perform a like-for-like replacement means that a more diversified portfolio strategy toward energy storage must be adopted in order to make a smooth transition to a lower carbon energy future. Such balanced energy storage portfolio would necessarily consist of some combination of:
- short-duration energy storage systems that are capable of maintaining power quality by meeting localized spikes in peak demand and buffering short term supply fluctuations. These could include supercapacitors, batteries and flywheels that can supply bursts of power quickly.
- Lower speed energy storage that can supply a lot of power and store a lot of energy. These systems, such as pumped hydro and thermal storage with concentrated solar power, are capable of shifting the seasonality of solar production and servicing the unique power requirements for large scale or sensitive power users in the commercial and industrial sectors.
This set of storage technologies would have to be linked up in a kind of chain, nested and tiered by end use, location and integration into the grid. Additionally, management systems will be needed to control how the storage technologies interact with the grid.
Currently without sufficient energy storage in place, utilities now use natural gas to fill in the gaps in electricity supply from renewable sources. Utilities use “peaker” plants, which are natural gas-fueled plants that can turn generation up or down to meet electricity demand, such as when solar output dips in the late afternoon and evening, while producing air pollution and greenhouse gas emissions in the process.
With natural gas consumption for electricity generation on the rise, would it be better to keep nuclear power while energy storage technologies mature? Although less polluting than coal, natural gas produces greenhouse gas emissions and has the potential to causeenvironmentally dangerous leaks, as seen in Aliso Canyon.
With nuclear, it is still not clear what to do with nuclear waste, and the disaster at Japan’s Fukushima nuclear power plant in 2011 highlights how catastrophically dangerous nuclear power plants can be.
Regardless of which situation you believe is best, it is clear that energy storage is the major limitation to achieving a carbon-free electricity grid.
California’s commitment to renewable energy sources has helped shift the state to using less fossil fuels and emitting less greenhouse gases. However, careful planning is needed to ensure that energy storage systems are installed to take over the baseline load duties currently held by natural gas and nuclear power, as renewables and energy efficiency may not be able to carry the burden.
Sophie Vorrath: Musk’s energy master plan: Is this the beginning of the end of the utility? July 27, 2016. When Elon Musk published part 2 of his Tesla Masterplan last week, it was his vision of a future where cars from a huge shared fleet of driverless electric vehicles could be summoned by the touch of a mobile phone app that dominated headlines.
But Musk’s vision for a world of energy self-sufficient households with solar and battery storage was equally ambitious – and threatens to be as disruptive to the world’s electricity industry as his autonomous shared vehicle plan could be to the automotive industry, not to mention Uber. http://onestepoffthegrid.com.au/musks-energy-master-plan-is-this-the-beginning-of-the-end-of-the-utility/
Will solar, batteries and electric cars re-shape the electricity system?, UBS, 20 July 16,
“…….Berkeley Energy Professor Daniel Kammen ably defended energy storage, ……. Energy storage is cost competitive already in some markets—unlike new nuclear, Kammen said, and its price is dropping on a steeper curve than the dramatic reductions seen in solar costs. Storage will be more effective in the decentralized energy grid that’s emerging, he continued, than nuclear could be.
“The dramatic ramp up in solar resulted in the dramatic realization that a diverse, decentralized system can provide the same critical features that we think about with a baseload highly centralized system,” said Kammen. “Not tomorrow, but in the time frame that we need it, it’s absolutely there.”….
Ball summarized: ”So the argument is that rather than having yesterday’s no-carbon technology, which is a very centralized big generation technology, you think the world now has tomorrow’s no-carbon technology, which looks like a ballet of lots of different sources ready to go.”
In addition to batteries, compressed air storage is cost competitive, Kammen said, and flywheel storage can deliver power in sub-milliseconds. And in time, electric cars, buses and other vehicles will be used as a storage resource, he said. That’s a strategy China is pursuing and that Kammen has suggested the rest of the world consider, not in the next five years, but a bit later as these technologies develop and proliferate.
Meanwhile, small modular nuclear reactors won’t be ready in time to meet the grid’s needs, he said, and conventional reactors are too expensive.
“If you want to bet on a robust-basic-research to an applied-research-deployment category,” Kammen said, “that far favors the storage revolution than it does the nuclear revolution.”…… Silicon Valley Energy Summit , Forbes 5 June 16
London borough installs 6,000 solar panels over marketplace http://www.theguardian.com/environment/2016/may/19/london-borough-installs-6000-solar-panels-on-market £2m scheme by Hounslow council on Western International Market will be biggest solar scheme by any local authority, and use batteries to store energy. A London council is unveiling a vast installation of 6,000 solar panels on a wholesale market rooftop, which it says is the largest such array put up by a local authority.
The London Borough of Hounslow says its £2m investment in solar, which has been installed on the roof of Western International Market, is also the first by a council to adopt battery storage to maximise the power from the panels.
The 1.73 megawatt (MW) array of 6,069 panels and four 60kW lithium batteries system now generates half the site’s required electricity.
The site is west London’s largest wholesale market for fresh produce and flowers, and uses around 3.5 megawatt hours (MWh) of electricity to provide climate controlled facilities to around 80 wholesalers and buyers – the equivalent of 1,750 homes a year.
Hounslow council, which owns the market near Heathrow Airport, says the solar system will contribute 2% of its carbon reduction target, cutting emissions by more than 780 tonnes a year.
It will also save £148,000 in energy costs which, along with £100,000 in generation tariff payments and £7,000 in export tariffs, means that the council expects to be £255,000 better off in the first year of operation.
Charles Pipe, energy manager at Hounslow, said: “From the very beginning, this project has been about reducing our carbon footprint and making an investment for the future. “But we have achieved so much more than that. Not only can we expect to see immediate savings on our electricity bills, but we are expecting to see a return on this investment in about five years.”
LG Electronics, one of Hounslow’s partners in the scheme, said it was the company’s largest solar panel installation in Europe and would deliver significant costs savings to the borough.
LG Solar’s UK senior solar sales manager Bob Mills said: “What’s more, the project has set the wheels in motion for further investment and research into the potential of battery storage, which is set to revolutionise the solar industry.
Chinese researchers develop new battery technology, EurekAlert, 25 Mar 16CHINESE ACADEMY OF SCIENCES HEADQUARTER A Chinese research team from the Shenzhen Institutes of Advanced Technology (SIAT) of the Chinese Academy of Sciences has developed a novel, environmentally friendly low-cost battery that overcomes many of the problems of lithium ion batteries (LIB). The new aluminum-graphite dual-ion battery (AGDIB) offers significantly reduced weight, volume, and fabrication cost, as well as higher energy density, in comparison with conventional LIBs. AGDIB’s electrode materials are composed of environmentally friendly low cost aluminum and graphite only, while its electrolyte is composed of conventional lithium salt and carbonate solvent.
The research, published in “A Novel Aluminum-Graphite Dual-Ion Battery,” recently appeared in Advanced Energy Materials (IF=16.146).
The discovery is particularly important given rising battery demand and existing LIB technology, which is reaching its limit in specific energy (by weight) and energy density (by volume).
LIBs are widely used in portable electronic devices, electric vehicles and renewable energy systems. Battery disposal creates major environmental problems, since most batteries contain toxic metals in their electrodes. According to the Freedonia Group, world battery demand is expected to rise 7.7% annually, reaching US$120 billion in 2019………http://www.eurekalert.org/pub_releases/2016-03/caos-crd032416.php
CAN LARGE-SCALE SOLAR POWER STORAGE BECOME A REALITY?, Stanford Engineering, An unexpected finding by a team of engineers could lead to a revolutionary change in how we produce, store and consume energy. By Glen Martin, 16 Feb 16, “……..Now a team led by William Chueh, an assistant professor of materials science and engineering, and Nicholas Melosh, an associate professor in the same department, has made a discovery that could make large-scale solar power storage a reality.
The breakthrough is based on the fact that ordinary metal oxides, such as rust, can be fashioned into solar cells capable of splitting water into hydrogen and oxygen.
So far it has been impractical to use water-splitting as a way to store the sun’s energy. One reason is cost-efficiency. Silicon-based solar cells, such as those used in rooftop solar arrays, are good at converting visible and ultraviolet light into electricity. But silicon cells waste the infrared light, which bears heat, beating down on them.”Standard cells utilize a relatively small portion of the spectrum, and the rest is lost as heat,” Chueh said.Until the recent Stanford experiments, it was believed that metal oxides also became less efficient as they became hotter. And since they were less efficient than silicon to start with, that made them less interesting as a water-splitting technology.The Stanford experiments change that misconception…………Discovering that heating up metal oxides produces more energy means that relatively simple engineering could be applied to heat these solar cells to enhance their efficiency.”You don’t have to add energy from an outside source,” said graduate student and team member Andrey Poletayev. “You can do it for free by concentrating solar radiation, either through a magnifying lens or parabolic mirrors.”Chueh believes that this discovery will refocus attention on developing metal oxides as cost-effective alternatives to silicon solar cells. Quite apart from their potential use in a day-to-night energy storage scenario, he envisions that pure hydrogen gas produced by water-splitting could be used to power vehicles or other machines directly and without pollution.”We can store these gases, we can transport them through pipelines, and when we burn them we don’t release any extra carbon,” said Chueh. “It’s a carbon-neutral energy cycle.”This research was supported by Stanford’s Global Climate and Energy Project and by the National Science Foundation. https://engineering.stanford.edu/news/can-large-scale-solar-power-storage-become-reality
This huge deal is the latest evidence that the battery revolution has arrived, WP By Chris Mooney December 15 At the Paris climate change conference earlier this month, all eyes were on some massive announcements in the solar and wind energy space — including plans in Africa to install 300 gigawatts of renewable energy capacity across the continent by the year 2030. A gigawatt is a billion watts — and this would be nearly double the electricity capacity that the continent currently supports.
Less noticed, however, is that a key enabling technology for solar — and for the future of clean energy — is also starting to grow: Energy storage. When solar systems are connected with batteries or other forms of storage, they can cease to be dependent upon whether the sun is shining and how strong its rays are at a given moment. Rather, solar energy can be stored and used at a later time. Including at night.
And now AES, a large energy company headquartered in Arlington, Va., has announced a very large deal in the battery space. It is gaining access to 1 gigawatt-hour worth of lithium ion batteries from Seoul-based LG Chem, a chemicals giant that also has a strong business in making lithium ion batteries for electric and hybrid electric vehicles. The batteries will be deployed in AES’s Advancion platform, which provides large scale grid energy storage to utility companies.
Power – in this case, a gigawatt – refers to the amount of electricity that can be discharged instantaneously. But when it comes to batteries, what’s also important is how long the battery can operate — its energy. Thus, 1 gigawatt hour would refer to the capacity to discharge that much power for one hour — but it could also refer to the ability to discharge 250 megawatts (or million watts) for four hours.
Either way, that’s a very large amount of batteries. For comparison, GTM Research recently forecast that the U.S. will deploy a record 192 megawatts of energy storage in 2015.
But for now, the biggest business for batteries isn’t in the home, where they can serve a backup role in the event of an outage or pair with a rooftop solar system; it’s on the grid, where there is a constant need to be able to manage shifting electricity demand at different times of the day. Batteries that can switch on automatically at key moments can provide a major grid service, which is why they’re seeing more and more demand.
Thus, AES is in effect packaging lots of batteries, provided by LG Chem, into large systems that large power companies can purchase and then install or integrate on the grid wherever they need this new capacity. AES directly advertises its batteries as the “complete alternative” to “peaking power plants.”
Want a Solar-Powered Home? Here’s a New Battery That Won’t Ignite
As solar panels and wind turbines spread worldwide, they’ll need batteries to store power for times when they don’t produce it. Harvard debuts a promising prototype. By Wendy Koch, National Geographic SEPTEMBER 24, 2015 If you dream of an off-grid house powered by the sun, plan on a battery to store energy for cloudy days—ideally, one that won’t catch fire. Harvard researchers might have just the fix.
“It is a huge step forward. It opens this up for anyone to use,” says Michael Aziz, Harvard University engineering professor and co-author of a study published Thursday in the journal Science. Because the battery is safe and non-corrosive, he says, it’s well suited for both businesses and homes, adding: “This is chemistry I’d be happy to put in my basement.”………http://news.nationalgeographic.com/energy/2015/09/150924-nonflammable-battery-could-charge-solar-homes/
In the end, the solution might lie on a smaller scale: giving everyone the power to store their own power. Tesla is one company of several in this game: it recently announced a device called the Powerwall, designed for homes and businesses. It uses the same batteries as electric cars to store energy, either from renewables or cheap night-time electricity, ready to be used during the day.
If such systems become commonplace, we might all become a little more aware of where our energy is coming from, and how our own behaviour affects its use and production
The battery revolution that will let us all be power brokers, New Scientist 22 July 15
Companies are racing to find better ways to store electricity – and so provide us with cheaper energy when and where we want it “……... Although they are still dwarfed in most respects by the bulky lead-acid batteries found in almost every car on the road today, in 2015, lithium-ion batteries will account for around a third of the money spent on rechargeable batteries globally (see “Turn it on”), and just under a sixth of the total energy stored, according to French research firm Avicenne.
Systems flexible enough to accommodate the ups and downs of solar and wind production can be made by adjusting the power at millions of homes and businesses on a minute-by-minute or even second-by-second basis. This approach requires no new hardware, some control software and a bit of consumer engagement.
Massive balancing act..……This is an enormous challenge to grid operators in this region. Massive fluctuations in power require equally massive storage devices that can charge when the wind is blowing, and discharge during periods of calm.
Now, the balance of supply and demand for power is primarily done by generating more power rather than storage.
Grid operators draw on what is called the balancing reserves obtained from fossil fuel generators or hydro plants, when available. These power plants ramp up and down their output in response to a signal from a grid balancing authority. This is just one of many ancillary services required to maintain a reliable grid.
Many states are now scrambling to find new sources of ancillary services, and the federal government is also searching for incentives: Federal Energy Regulatory Commission (FERC) orders 745, 755 and 784 are recent responses by a government agency to create financial incentives for responsive resources to balance the grid.
Are batteries the solution?
Storage is everywhere, but we have to think beyond electricity…………..
Through local intelligence – in the form of a chip on each device or a home computer for many devices – the collection of one million pools in Florida can be harnessed as massive batteries. Through one-way communication, each pool will receive a regulation signal from the grid operator. The pool will change state from on to off based on its own requirements, such as recent cleaning hours, along with the needs of the grid. Just as in the office building, each consumer will be assured of desired service.
Pools are, of course, just one example of a hungry but flexible load.
On-off loads such as water pumps, refrigerators or water heaters require a special kind of intelligence so that they can accurately erase the variability created from renewable generation. Randomization is key to success: To avoid synchronization (we don’t want every pool to switch off at once), the local intelligence includes a specially designed “coin-flip”; each load turns on or off with some probability that depends on its own environment as well as the state of the grid.
It is possible to obtain highly reliable ancillary service to the grid, while maintaining strict bounds on the quality of service delivered by each load. With a smart thermostat, for example, indoor temperature will not deviate by more than one degree if this constraint is desired. Refrigerators will remain cool and reliable, and pools will be free of algae………
Today, about 750,000 homeowners in Florida have signed contracts with utility Florida Power & Light, allowing them to shut down pool pumps and water heaters in case of emergencies. How can we expand on these contracts to engage millions of homeowners and commercial building operators to supply the virtual storage needed? Recent FERC rules that offer payments for ancillary services for balancing the grid are a valuable first step in providing incentives.
It is possible that little incentive is required since we are not subjecting consumers to any loss of comfort: it is the pool or fridge that provides flexibility, and not the homeowner.
A sustainable energy future is possible and inexpensive with a bit of intelligence and flexibility from our appliances. https://theconversation.com/could-one-million-smart-pool-pumps-store-renewable-energy-better-than-giant-batteries-41937
What is certain is that the electricity equation will look very different in a few short years, and it looks like, for the first time in many years, that ordinary consumers will hold a bit more of the power
How home energy storage is going to change the way we think about power, Adelaide Now, CAMERON ENGLAND SUNDAY MAIL (SA) MAY 31, 2015 WHEN Elon Musk launched the Tesla Power Wall earlier this month, it was done in true Silicon Valley style.
The charismatic chief executive enters stage right, sans tie, and makes a pronouncement that his new product will change the world — cue rapturous applause from the audience and because this is the United States, whooping.
The thing about Musk’s pronouncement is that it’s most likely true.
It might not necessarily be his company — critics are divided as to whether Tesla will be the market leader it’s portraying itself as — but home and business energy storage is soon to change the way energy utilities, homes and governments think about power……..
Batteries allow homes and especially businesses to employ “peak shaving” — if power prices spike, flick over to using your own solar power and save money, or if the grid power is cheap, suck it out and sell it back later at a higher price.
Or simply save up the solar power your rooftop panels produce during the day for use in the evening, when your demand might be higher……..
Tesla Power builds on the Tesla Motors technology — relatively standard lithium ion batteries with smart software to help them interact with the grid. The initial interest has been huge. The company recently reported early orders of 50,000 to 60,000 batteries, or as Musk put it, “It’s like crazy off-the-hook”.
Effectively the company is sold out until the middle of next year and its huge new factory will not be big enough to keep up with demand.
At $US3000 for the battery and $US7000 installed with solar panels (US prices) the system makes it economic for houses to become much less dependent on grid power.
UBS estimates that in Australia, the system would pay itself back in six years.
But Tesla is not the only game in town — although it almost certainly has the best PR machine. Continue reading
in sum – cheaper, more easily available energy storage helps at the scale of the power grid, and also at the level of our homes, to further advantage cleaner, renewable energy. So if the economics of storage are finally starting to line up – and its business side to ramp up – that can only be good news for the planet.
Tesla’s battery announcement shows the coming revolution in energy storage, Sydney Morning Herald May 2, 2015 Chris Mooney “……Tesla announced that it is offering a home battery product, which people can use to store energy from their solar panels or to back-up their homes against blackouts, and also larger scale versions that could perform similar roles for companies or even parts of the grid.
For homeowners, the Tesla Powerwall will have a power capacity of either 10 kilowatt hours or 7 kilowatt hours, at a cost of either $US3500 or $US3000………
Tesla isn’t the only company in the battery game, and whatever happens with Tesla, this market is expected to grow. A study by GTM Research and the Energy Storage Association earlier this year found that while storage remains relatively niche – the market was sized at just $US128 million in 2014 – it also grew 40 per cent last year, and three times as many installations are expected this year.
By 2019, GTM Research forecasts, the overall market will have reached a size of $US1.5 billion.
“The trend is more and more players being interested in the storage market,” says GTM Research’s Ravi Manghani. Tesla, he says, has two unique advantages – it is building a massive battery-making “gigafactory” which should drive down prices, and it is partnered with solar installer Solar City (Musk is Solar City’s chairman), which “gives Tesla access to a bigger pool of customers, both residential and commercial, who are looking to deploy storage with or without solar.”
The major upshot of more and cheaper batteries and much more widespread energy storage could, in the long term, be a true energy revolution – as well as a much greener planet. Here are just a few ways that storage can dramatically change – and green – the way we get power: Continue reading
Tesla Motors, maker of the Model S supercar and soon to be launched Model X, announced its Powerwall home electricity storage solution under the Tesla Energy brand this week. There will be two available units of 7 kilowatt-hour and 10kwh capacity offered at $3,000 and $3,500 respectively. They can also be stacked for homeowners who wish to store more energy.
So as not to leave commercial customers out in the dark, Tesla Energy will also offer the Powerpack.
Tesla Moves to Make Renewable Energy More Viable http://www.huffingtonpost.com/patrick-roth/tesla-moves-to-make-renew_b_7190196.html 05/01/2015 Imagine a world in which all our energy needs comes from clean, renewable sources. Every building could be covered and powered by solar panels. Transportation could be provided by electric vehicles. Clean and free electricity provided by sun and wind could be used in real time and stored in batteries for later use. Fossil fuels could be regulated to the fuel of last resort. It may not be the stuff of science fiction any longer. If Tesla CEO Elon Musk has his way, this is the future we are headed towards.
Solar and wind energy have long been attractive renewable energy sources. Once the photovoltaic panels and wind turbines are manufactured, they can create many years of electricity with zero harmful emissions and little if any maintenance. In recent years the cost of solar has plummeted, leaving it on par with fossil fuels. The problem however has been in the less than constant ability of renewables to create electricity. Solar cannot produce as much electricity in inclement weather or any at night. Wind is intermittent. Also, unlike more conventional fossil fuel burning power plants, capacity cannot always be increased during peak periods of need.
In order for solar and wind-generated power to be more than energy grid add-ons, they need to have a way to store their energy for use during off-peak or low production periods. Batteries are the best way to store energy during periods of peak production to be used later. However, no major company has offered an easily-scalable battery storage solution to meet these needs – until now. Continue reading
This new Tesla battery will power your home, and maybe the electric grid too, WP, By Brian Fung February 12 Tesla is working on a battery that can power your home and even help large-scale utilities store energy more efficiently, according to company chief executive Elon Musk.
On an investor call Wednesday, Musk said the designs for a home or business battery are already complete and will likely be unveiled to the public “in the next month or two.” Production could be as little as six months away, he added…..
Tesla’s battery and charging technology could ultimately wind up saving you money on your electric bill. Although many of today’s homes draw energy directly from the electricity grid, the spread of cheap solar panels means it’s never been easier to generate some of your own energy. Storing renewables efficiently has been a big bottleneck for consumers and for utilities alike, but if Tesla’s stationary battery takes off, it could change the way electricity is priced and traded on a market scale…….http://www.washingtonpost.com/blogs/the-switch/wp/2015/02/12/this-new-tesla-battery-will-power-your-home-and-maybe-the-electric-grid-too/?tid=pm_business_pop
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