Flow batteries are large liquid-filled tanks that are mostly used to store energy for the power grid. A flow battery’s electrolyte is stored in two tanks that are separate from the cell itself, and the flow battery generates electricity when the liquid electrolytes, which are mixed with energy-storing materials, flow through the two sides and react with the electrodes in each side of the cell.

The idea, which has been around for decades, is to create a lower-cost battery option than, say, lithium-ion batteries. Power companies like them because the batteries are rechargeable, and can be scaled up and down by adding more tanks. Companies working on this technology include EnerVault, ZBB Energy, Prudent Energy, RedFlow, Primus Power and Deeya Energy.

ZBB’s flow battery

Sun Catalytix tells MIT Tech Review that it hopes to have a prototype of its flow battery later this year, which it can test out with customers, and then raise more funds for additional product development at that point. The end product is supposed to be a 1 MW flow battery that can last four to six hours and fit inside a 40-foot shipping container.

It’s not uncommon for cleantech startups — or any startup — to pivot and shift their plan as they progress. The artificial leaf was in the research phase and the company realized that commercializing it would take many years and lots of money. Though, as this New Yorker article points out Nocera has a bit of a reputation for hyping his discoveries.

The problem, though, is that funds for commercializing next-gen energy technologies are very tight these days. And Sun Catalytix already received a $4 million grant from the Department of Energy’s ARPA-E program, as well as a $9.5 million Series B round led by India’s Tata and including existing investor Polaris Venture Partners.

Venture capitalists have started to move away from investing in energy tech, and government funds could be tight in 2013, too. Funding could be particularly difficult for an early stage technology, where there are clear competitors that are farther ahead.

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But that promise remains just that, given that batteries of any kind are still mostly being tested in pilot projects by power producers and utilities. There’s has been some investment and innovation in the space in recent years: a flow battery startup called EnerVault announced this week that it’s raised a $15.5 million B round to help it install its first demonstration project in California’s central valley.

Flow battery isn’t as well known as lithium-ion battery partly because we don’t use it in our daily lives like we do with lithium-ion batteries, which run our mobile phones and computers. So what makes up a flow battery?

How do flow batteries work?: In contrast to a lithium-ion battery, where the energy-storing materials and electrolyte are enclosed in a cell, a flow battery’s electrolyte is stored in two tanks that are separate from the cell itself. The flow battery generates electricity when the liquid electrolytes, which are mixed with energy-storing materials, flow through the two-half cells and react with the electrodes in each side of the cell. Flow battery developers are experimenting with different types of energy storing materials, such as iron, vanadium, zinc and bromine.

EnerVault’s design uses iron in one tank and chromium in the second tank. Commonly the two electrolyte tanks hold different energy storing materials. But for vanadium flow batteries (an increasingly important and advanced type of flow battery) vanadium is used in both electrolyte solutions. The Electric Power Research Institute says vanadium flow batteries are a more mature technology than zinc- and iron-based flow batteries, which are mostly in R&D or field demonstration stages.

Flow battery makers like to point out that the use of external storage tanks means a flow battery system can be scaled up and down easily. Flow batteries are also rechargeable; the electrolytes can last a really long time, and typically use abundant materials — therefore can be a more affordable option. At the same time, flow batteries tend to be bulky, are not easily moved and the components have to be assembled on site.

The history of flow batteries: Flow batteries may not be common, but the idea has been around since the 19^th century. Many companies, along with NASA, have investigated various types of flow battery technologies in recent decades. NASA encountered a host of technical difficulties, such as significant losses of energy during charge and discharge. Creating a good separator for the ion exchange membrane also is a challenge.

What is the market for flow batteries like? Flow battery developers are targeting some of the same customers that competing battery technology developers — from lithium-ion to lead acid makers — are aiming for: power companies and utilities. Utilities are sought-after customers, because they are facing a growing need to manage the variable supply of wind and solar electricity, and they can use batteries to store solar and wind energy and release it when demand peaks.

Businesses and consumers also are potential customers for battery companies. Batteries can store electricity from, say, a rooftop solar system, and then draw energy from the batteries after the sun goes down. Battery owners can even sell the stored energy to their utilities when electricity pricing is high if they are located in states that allow such a practice. China is shaping up to be a large market for batteries of all types, and flow battery makers such as ZBB Energy have developed joint ventures with Chinese companies. Last week, ZBB said it made the first shipment of its new flow battery technology to its Chinese partner, Meineng Energy.

The players: Aside from ZBB and EnerVault, other flow battery makers include Prudent Energy, RedFlow, Primus Power and Deeya Energy.

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Analysts with Lux say applications such as cell phone base stations, data centers, and pop-up military bases — disconnected from the power grid and often in remote locations — are an intermediary market that energy storage companies should tap as the EV and grid-storage markets slowly develop. Lux says the off-grid storage market will grow 6 percent over the next five years, from a size of $9.9 billion in 2011 to $13.5 billion in 2016, and newer technologies like fuel cells, fly wheels, advanced batteries and ultracapacitors will have solid chances of scoring in this market.

For data centers, energy storage technologies are used as an uninterruptible backup power supply (UPS), which provide continuous power if the grid fails. Internet companies need to keep high-traffic websites running even if there’s a blackout. Currently, UPS services often rely on large blocks of lead acid batteries or generators, but flywheels and ultracapacitors could score 10 percent of the datacenter UPS market by 2016, says Lux, and lithium-ion batteries could carve out another 6.8 percent of the UPS market by then. The number of data centers will only grow throughout the world as more and more devices and people get connected.

Cell phone base stations and telecommunication networks are another type of infrastructure that will continue to get deployed as more people, particularly in the developing world, buy cell phones. Base stations provide a wireless signal for cell phones in a certain area to pick up the signal, so phone companies deploy these all over the place, and these base stations need back-up power if the grid happens to go down. Often, that back-up power is provided by diesel generators.

Lux estimates lithium-ion batteries could gain 5.8 percent of the market for telecom backup capacity by 2016, and fuel cells will gain a substantial share, too, and are already being used more frequently by telcos in rural and isolated places. Sprint is doing a 250 fuel cell test in the U.S. using a Department of Energy grant. Vodafone spinout P21 is testing mobile telecom backup fuel cells in Europe, and Deeya Energy is shipping its flow batteries to back up cell towers in India.

Eventually, the grid-tied energy storage market will break out, and the folks at the Electric Power Research Institute (EPRI) peg 2012 as a turning point because by then, companies that have collectively received more than $250 million in federal stimulus funding are expected to complete research and development work and move into field trial stages in the U.S. Electric vehicles are also supposed to one day become more mainstream, but will take years to reach any kind of mass adoption.

Image courtesy of emperley3.

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Primus Power has been building a flow battery farm that when completed offer between 25 MW to 75 MW on energy storage capacity for the Modesto Irrigation District. The battery farm will be Primus Power’s demonstration facility and will provide storage technology to make up for the variable nature of wind power in the area. The company said these new funds will go towards completing that facility and for wider scale commercialization.

While I don’t know all the intricacies of Primus Power’s technology, flow batteries, in general, use large storage tanks full of electrolytes and pumps that circulate the solution throughout the system (see image of Sumitomo’s tech). Flow batteries can be safer and more reliable (compared to lithium-ion batteries), can be lower cost than other forms of energy storage, and can be deployed relatively quickly. Some flow battery technology can run around $100 per kWh, compared to some batteries which can range in cost between $200 per kWh to $500 per kWh and up to $1,000 per kWh for more advanced batteries.

According to a Department of Energy website, Primus Power is working on an inexpensive metal electrode for a flow battery, and is also employing manufacturing processes common in high volume metal production to develop the electrode. Primus Power was awarded two grants from the Department of Energy for the innovation. Greentech Media reported earlier this month that the technology is based on a zinc bromine system.

Other startup flow battery makers include EnerVault and Deeya Energy. Deeya Energy is a 6-year-old company that has raised $53 million from Technology Partners, BlueRun Ventures, Draper Fisher Jurvetson and New Enterprise Associates and has redox flow battery inventor Lawrence Thaller as a technical adviser. EnerVault has raised $3.5 million in venture funding, from Oceanshore Ventures and U.S. Invest.

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But a new bill in the California legislature could force the issue. Assembly Bill 2514 (pdf), written by state Rep. Nancy Skinner and backed by state Attorney General Jerry Brown, would require that the state’s utilities match 2.25 percent of their peak loads with energy storage by 2014, and 5 percent by 2020 — a goal that could equate to about 3,400 MW of storage capacity in the next 10 years.

Landmark Bill, Will It Work?

It’s the first such mandate to be introduced at the state level, and “the most exciting piece of energy storage legislation that we’ve seen on this topic to date,” Janice Lin, director of the newly formed California Energy Storage Alliance, said Thursday at the U.C. Berkeley Energy Symposium. The alliance includes battery makers such as EnerVault, A123Systems, Deeya Energy, Prudent Energy, Xtreme Power, ZBB, Powergetics and AltairNano, as well as flywheel maker Beacon Power, air conditioner energy storage maker Ice Energy, solar panel giant Suntech and oil, gas and energy services giant Chevron. That list is representative of the range of technologies that could play a role in helping California meet such a challenging goal.

But will a mandate forcing utilities to meet energy storage thresholds help change the current economics of some of the newer energy storage technologies? The problem with some of the technologies like batteries is that they’re just too expensive.

California may be better suited than most states to try it out, Lin said. The state’s Self Generation Incentive Program already offers incentives for energy storage at industrial and commercial sites, she noted. In particular the California ISO — the entity that manages the state’s grid — is considering adding storage to the list of approved sources for ancillary services, or power that’s paid more money to meet peak demand needs, she said.

On the other hand a mandate that’s too aggressive could lead to a couple of negative outcomes, said Hal La Flash, PG&E’s director of emerging clean technology policy. First, it could force utilities to buy systems from out-of-country providers like NKG and fail to assist U.S. storage companies. Or, it could lead to a situation where regulators, seeing that utilities are hurting customers by spending on mandated storage that doesn’t pay for itself, change the regulations, further roiling the storage market.

California’s energy storage quest could be helped along by federal action. DOE has given a total of $165 million in stimulus grants to energy storage projects across the country. That, along with incremental improvements in performance and the price decreases that come with expanded manufacturing capacity, could make 2010 a breakout year for energy storage, according to IDC Energy Insights.

Then there’s the Storage Technology of Renewable and Green Energy Act of 2009 (S. 1091), a bill that would offer tax credits to energy storage that was introduced into Congress last year. While it hasn’t progressed since then, this year could see it re-emerge.

Cali’s Energy Storage Choices

Whether or not AB2514 passes, the state may not have a choice but to build an equivalent amount of storage, according to Ed Cazalet, CEO of erstwhile energy storage developer Megawatt Storage Farms. He believes that California will need about 4 GW of storage by 2020, if the state is to meet its 33 percent renewable goal without crashing the grid with all that on-again, off-again power.

While California has about 1,500 MW of energy storage today, that’s almost entirely made up of pumped hydro — that is, water that’s pumped uphill when power is cheap, then released to spin a turbine to meet peak demands. Examples include Pacific Gas & Electric’s 1,200 MW Helms Pumped Storage Facility near Fresno, Calif. But because sites to build new pumped hydro are hard to find geographically and hard to build politically, the state will need to find other alternatives, Cazelet said.

There are some large-scale energy storage projects being planned in the state. PG&E in November got a $25 million Department of Energy grant to study the potential for a 300 MW compressed air energy storage (CAES) system in California’s Central Valley, for example. But La Flash noted that the utility is now engaged in verifying that the porous rock geology of that CAES site will work for storing energy as compressed air — the only two working CAES plants in the world, in Alabama and Germany, use salt domes instead. Just how fast the PG&E project could be built, “we won’t know until we get to that point” of verifying the geology works, he said.

Then there’s thermal storage, which in the simplest terms involves making ice at night when power’s cheap, then using it to augment air conditioners during the hot summer days when California sees peak power demand. Ice Energy, which makes such an air conditioning unit, just won a 53 MW contract with the Southern California Public Power Authority to install those distributed units across thousands of rooftops.

What about batteries? Grid storage batteries are increasingly coming online, though mostly in pilot projects, at least in the U.S. PG&E, for example, is testing out 4 MW of high-temperature sodium-sulfur batteries in San Jose for grid balancing purposes, and American Electric Power has installed about 7 MW. Some grid storage applications for everyone’s favorite electric vehicle battery technology, lithium ion, are being pursued — Southern California Edison won $4 million in DOE stimulus grants to deploy an 8 MW lithium ion battery to help integrate wind power into its energy supply. Other utilities are likely looking at lithium-ion for projects to bring small batteries into neighborhoods to back up the distribution grid, like the project AEP is planning with $75 million in DOE smart grid grants.

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Until recently, those batteries were being developed in Vancouver, Canada by a company called VRB Power Systems — that is, until Prudent Energy bought out the struggling company’s assets in Jan. 2009. Apparently new investors Northern Light Venture Capital and Sequoia Capital China, and existing investors DFJ and DT Capital, think Canadian technology and Chinese manufacturing are a winning combination.

China is the biggest financial backer of cleantech in a world that’s seen governments take over that critical role from banks and venture capital firms over the past 18 months of economic distress. According to the Stern report released in April 2009, the Chinese government had set aside some $200 billion in cleantech stimulus funding over the coming years, compared to about $112 billion from the U.S. government.

This year should see government stimulus jump to a global $182 billion, up from $79 billion last year, according to an analysis by the Cleantech Group. The cleantech research firm also reports that Asian companies “absolutely dominated” IPO and M&A activity last year, including the world’s biggest cleantech IPO of 2009, the $2.2 billion fourth-quarter offering of wind power producer China Longyan Electric Power Group.

He who pays the piper, calls the tune — and in China’s case, that’s expected to mean a lot more focus on leveraging the country’s manufacturing might and cost advantages to mass-produce technologies developed both at home and abroad. A recent example is ECOtality, the Scottsdale, Ariz.-based electric vehicle charging system maker that just announced a $300 million credit line from Chinese partner Shenzhen Goch Investment. That money isn’t just going to build equipment for export. While ECOtality’s subsidiary eTec also won about $100 million in U.S. stimulus grants in August, China is expected to build about half of the world’s EV charging station in the next five years or so, according to Pike Research.

Depending on one’s point of view, China’s emergence is either a major threat to U.S. competitiveness, or an enormous market opportunity for U.S. cleantech companies and U.S.-Chinese research partnerships. China has already become the world’s biggest maker of solar panels and wind turbines.

While that growth has been built on export markets, China is also developing some of the largest wind and solar projects in the world within its borders, with the goal of getting one-fifth of its power from renewable sources by 2020. China has also set its sights on building a nationwide smart grid that could cost about $10 billion a year through 2020, Bloomberg reports, and this has drawn the interest of such major smart grid players as General Electric and IBM.

Prudent Energy’s batteries might find a role to play in these smart grid plans. Flow batteries share characteristics with fuel cells, in that they’re powered by liquid catalysts that can be refueled or recharged. While flow batteries have long cycle lives and lower costs than other battery technologies, they don’t tend to be as efficient at storing power, meaning that pound for pound they’re best suited to stationary applications — say, storing wind or solar power for the grid.

Other flow battery startups include EnerVault, which recently raised $3.5 million from Oceanshore Ventures and U.S. Invest, Deeya Energy, which raised $30 million in May from Technology Partners, BlueRun Ventures, Draper Fisher Jurvetson and New Enterprise Associates, as well as Premium Power and ZBB Energy Corp.

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According to an executive summary from EnerVault, the company plans to use the funding to build a prototype that can demonstrate that their flow battery technology can scale to megawatts, as well as for adding on staff and attracting new customers. Once the prototype is built, EnerVault says it will look for follow-on and government funding to build a full-scale field-deployable system.

Why will flow batteries be so important for the future of the smart grid? The technology — which generally uses large storage tanks full of electrolytes and pumps that circulate the solution throughout the system — has had decades of research, could offer one of the lowest cost grid storage options out there, and can be safer and more reliable than other energy storage technologies like advanced batteries, which can become overheated.

EnerVault CEO Craig Horne told us last May that the company’s flow battery can run around $100 per kWh, but says that price could also come down when the company scales up production. In comparison, lithium-ion batteries can cost from $200 per kWh to $500 per kWh and up to $1,000 per kWh for more advanced batteries with more expensive materials.

Like other forms of grid energy storage, flow batteries will become increasingly important as utilities look to add clean power to their portfolios. In particular utilities that have state renewable portfolio standards will need to make sure that the intermittency of the clean power (the sun and wind are only available at certain times of day) that they add on doesn’t make their grids more vulnerable.

Other flow battery companies are raising funds, too. Last year flow battery maker Deeya Energy closed a $30 million financing round from Technology Partners, BlueRun Ventures, Draper Fisher Jurvetson and New Enterprise Associates. Deeya is a 5-year-old firm that hails redox flow battery inventor Lawrence Thaller as a technical adviser and has raised $53 million.

Image of flow battery courtesy of Electric Storage Association.

Pictures and Videos:

• Save the pictures and videos created with your phone onto your computer
• Transfer files between your computer and your phone
• Touch up your photos with intuitive editing tools
• Create photo albums and slideshows
• Email pictures to friends and family

Music:

• Transfer songs and playlists from your computer to your phone
• Rip and burn CDs
• Add to your collection by browsing the millions of MP3s in the Verizon Wireless Media store

While there’s no charge for the V CAST Media Manager software, it does have at least one major limitation. When browsing the FAQs, I noticed this one:

“V CAST Media Manager also allows you to transfer DRM-free files from your computer to your phone; however, DRM and DRM-free files are not able to be transferred from the phone to a computer.”

Essentially, any music you purchase directly on your handset can’t be moved to the PC with this software solution. That includes DRM-free music, which is simply tragic. My gut says that Verizon would rather sell you the song a second time as opposed to have you share it across multiple devices.

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The above image is the not-often-seen official unlock notification, as displayed in iTunes. The dialogue succinctly confirms that the user’s iPhone, in this case a 3G, has been unlocked and can now be used on any carrier. Note the Apple logo at the top left — this is a result of an official unlock sanctioned by Apple.

Read on to find out how I legally unlocked my iPhone 3G.

In June, while over 1 million early adopters in the U.S. picked up their brand new iPhone 3GS devices, I was anxiously waiting for the official launch in my current country of residence, Finland. I picked up my iPhone 3GS in Helsinki just two weeks ago, when it was finally launched by Sonera.

Regarding Sonera, think of it as a less-repugnant version of AT&T. As the exclusive distributor of the iPhone over in Finland, Sonera has turned out to be a somewhat benevolent carrier. The carrier’s unlimited data plan is reasonably priced, and home hacking your iPhone to tether to your Macbook is positively encouraged.

And now I’ve discovered that Sonera is also happy to lend a helping hand in unlocking your old iPhone 3G. When the 3G was released last year, Sonera customers had to sign up for a two-year contract. When upgrading to the iPhone 3GS, those same customers are given the option to pay off the remainder of their original 3G contract. Paying off the contract, and thus completing the two years prematurely, entitles the customer to have their iPhone 3G unlocked.

The helpful assistant at the Sonera store made a note of my IMEI number and then passed it onto his boss — after that there’s a special piece of software that only his boss is authorized to use. This mystical application submits the IMEI to Apple, which in turn authorizes the device for unlocking.

I was advised that when the iPhone 3G was next synced with iTunes, it would be unlocked. Minutes later, back at home, I connected the iPhone 3G to iTunes and received a new carrier settings update. After downloading and installing the update, Apple’s official iPhone unlock screen appeared.

Going the legit route was a much more painless process than using a proxy SIM or the Dev Team’s unofficial unlock. Also worth noting is that, unlike some of the illicit approaches, this unlock is permanent: I’ll be able to keep updating the iPhone’s OS without losing the ability to use any carrier SIM in the device.

It was a surprisingly quick, easy and free unlock for me, although I’d be very interested to find out if any of our readers around the world have had similar success in unlocking their iPhones.

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Notable Quote

“Allow me to say this: Get over it already. I might not appear to be a Twitter snob, but I am a big enough jerk to tell you to suck it up! Ha! But seriously, quit crying. You know what seems like the central message of these complaints is? It’s the same thing with most Twitter-related complaints: ‘You don’t follow me and you don’t use Twitter the way I, Self-Appointed Social Media Guru, use Twitter.’ Better to be seen as a snob than a self-absorbed whiner, I say. There’s no crying in Twitter.” – AdAge journalist Ken Wheaton, after readers complained about the mag’s list of “25 Media People You Should Follow on Twitter.“

Notable News

Dish Network ordered to pay $103 million plus interest to TiVo in a years-old patent infringement case (Associated Press)

Apple’s flagship retail store on Fifth Avenue in Manhattan booked $440 million in yearly sales (NY Post)

Orthopedists are reporting cases of “cell phone elbow,” a repetitive strain injury caused by holding a cell phone for too long (CNN)

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