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Floating Wind Turbines Headed for Offshore Farms

Floating wind power is no longer science fiction. Promising results from five test platforms operating worldwide—including three in Japan—are turning into project plans for a first generation of floating wind farms. Industry analyst Annette Bossler, who runs Bremen, Maine-based Main(e) International Consulting, predicts that the number of test platforms will nearly double over the next two years and that commercialization is within site. "By 2018-2019 you will start to see the first really large-scale commercial use of floating platforms," predicts Bossler.
 
Putting wind turbines on offshore platforms akin to those developed for the petroleum industry provides a means of exploiting high-quality offshore winds—which are stronger and more consistent than onshore winds—in waters too deep for today's bottom-fixed foundations. The Department of Energy calls floating wind the future of offshore wind because over 60 percent of U.S. offshore wind resources—and nearly all of those off the West Coast—blow over deep water.
 
Last month, Seattle-based Principle Power secured $47 million in federal funding to test that potential 29 kilometers out from Coos Bay, Oregon. It has partnered with Rhode Island-based offshore wind developer Deepwater Wind to tether platforms for five 6-megawatt wind turbines in over 300 meters of water—way beyond the 50-meter maximum depth for fixed foundations such as those that Deepwater Wind plans to use at its East Coast sites.
 
Floating turbines also offer potential cost savings. Floating platforms and their turbines are fully manufactured on shore, then towed out and tethered to the seabed. By contrast, fixing foundations to the seabed and then bolting on massive turbines requires specialized vessels, which cost upwards of US $200 000 per day to rent—whether or not the weather permits their use.
 
Bossler says floating platforms can also achieve cost savings through serial manufacturing. Whereas fixed foundations must be tailored to each turbine site's depth and seabed conditions, every platform in a floating array can be identical.
 

Prototype testing is assuaging doubts about floating platforms' ability to stabilize massive offshore wind turbines against wave action as well as their ability endure punishing offshore storms. Principle Power's array of 6-MW turbines will sit atop larger versions of a prototype that has carried a 2-MW turbine in Portuguese water since 2011 (photo at right / Principle Power). The semi-submersible platform is, like a glacier, mostly below water; its stability derives from water moving around the platform, as well as ballast water moving within it.
 
This month also marks one year of operation of a floating test turbine in Penobscot Bay (photo at top). It remains the only offshore wind turbine in U.S. waters. The 20-kilowatt prototype installed by a University of Maine-led consortium is just one-eighth the size of a 6-MW turbine. But its smaller scale actually provides an accelerated means of "de-risking" the design, according to Habib Dagher, the University of Maine structural engineer and composites expert who directs its DeepCwind Consortium.
 
Dagher says the platform relies only on water flowing around it for stability, yet is proving extremely stable through waves that—given its 1:8 scale—equate to 23-meter hurricane-scale assaults. "It saw 100-to-500-year storms relative to its size, and its maximum inclination angle was just 5.9 degrees off of vertical," says Dagher.
 
While Dagher's consortium lost out to Principle Power in the current round of DOE project funding, its plans to install two 6-MW turbines off Maine's coast may yet hold water. Maine has only deep water, and state regulators eager to jumpstart offshore wind development guaranteed DeepCwind a generous 23 cents per kilowatt-hour for its power. That power purchase deal is worth over $240 million, says Dagher, and is something that other U.S. offshore wind developers are struggling to secure.
 
Then there is DeepCwind's unique materials technologies, which it asserts could slim the cost of offshore wind power by more than half by the mid-2020s. DeepCwind replaces steel with corrosion-resistant concrete in its platform and with comparatively lightweight composites in its turbine tower.
 
Bossler says cost reduction will be critical to commercializing floating wind power. This is true even in Japan, where idled nuclear plants and soaring power costs are accelerating floating wind development. But she declines comment on whether DeepCwind's solution is the way forward. "I do work for a competitor," she says.

China to Follow U.S. on Limiting Carbon Emissions?

Advocates for action on climate change have long urged the United States to make the first major move in limiting carbon dioxide emissions, with the hope that other big emitters around the world would follow suit. That seems to actually be happening now: only days after the United States announced a new rule that will cut emissions from power plants by 30 percent by 2030, China made some noise about instituting a carbon cap of its own.

As the Guardian reported on Tuesday, He Jiankun, chairman of China's Advisory Committee on Climate Change, told a conference that the Chinese government plans to limit the country's emissions both "by intensity an absolute cap." That would be huge, if true—developing nations like India, as well as China, have long promised only to limit carbon emissions based on intensity, meaning as a function of the country's economic growth. But China passed the United States way back in 2006 to become the world's champion in CO2 emissions; reducing the total amount is the only thing the atmosphere and a warming planet care about.

But we can't rejoice just yet. There is no official word out of China, and He did backtrack later in the day saying he was merely stating his personal views rather than any official position. And of course, the specific level of any absolute cap will be critical to assessing whether it will really help. China's previous CO2 goal was a 40 to 45 percent reduction in carbon intensity, compared to 2005 levels, by 2020. The country did launch a pilot carbon trading program in Shenzhen last year, but again, an absolute limit on emissions country-wide would represent an enormous shift in policy.

If China does set a cap, and the United States pushes ahead with its new 30 percent reductions from power plants rule, the landscape will be dramatically different as countries head to Bonn, Germany, for this year's round of climate talks. The talks in past years have ranged from downright useless to mildly promising (very mildly), but with the two biggest CO2 culprits in the world on board for actual, meaningful reductions, there may be a chance to convince others to jump in as well. As noted by Quartz this week, India in particular remains an outlier, and will account for a huge proportion of emissions increases in the 2020 to 2040 range.

Nothing concrete is expected out of Bonn this year, but there is optimism that next year's talks, COP21 in Paris, will result in a firm agreement. In a teleconference last year, The United Nations' top climate official Christiana Figueres stressed that no country was doing enough just yet on this front, and added some confusing explanations for why the last time there was optimism surrounding these negotiations, at COP15 in Copenhagen in 2009, it was an abject failure: "What is very different is that we all went to 2009 having made our own decision that governments had to come to an agreement. But there was actually no commitment of governments to come to an agreement." So, we had to agree to agree before actually agreeing.

How exactly coal-dependent countries like China will limit and eventually diminish their emissions is still up in the air, of course. But even mentioning an absolute cap is big step from where we've been.

Ford and Samsung Team Up on Regenerative Braking for Non-Hybrids

After a decade of research, a revolution in batteries could be coming to conventional cars.

Ford and Samsung SDI have partnered to bring hybrid drive technology to Ford’s line up of non-hybrid vehicles to increase fuel economy. The technology, a decade in the making, pairs a traditional lead-acid battery with a lithium-ion battery to allow for regenerative braking.

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Construction of Ice Wall Begins at Fukushima Daiichi

Construction has begun on the "ice wall" at the shattered Fukushima Daiichi nuclear power plant, TEPCO announced today. This underground wall of frozen soil is intended to prevent groundwater from flowing into the reactor buildings, where it mixes with radioactive materials. Every day, about 400 tons of groundwater flows into the reactor basements.  

Since the meltdowns of March 2011, TEPCO has been trying to capture this contaminated water, store it safely, and treat it to remove the radioactive materials. It's an understatement to say that the company has had some trouble with this process. Storage tanks have leaked, and it took a long time to get the water treatment systems working properly. 

Stopping the contamination of groundwater is an important step in Fukushima Daiichi's 40-year decommissioning process. Right now, TEPCO is constantly building tanks to store the ever-accumulating water. Once the groundwater is kept out of the reactor buildings, TEPCO can focus on the radioactive water that's leaking out of the perforated reactors themselves.

In the video below, TEPCO explains that the ice wall technology is similar to that used in ice skating rinks. Pipes of coolant are inserted into the ground, which freeze the soil around them all the way down to the bedrock. The ice wall will redirect the groundwater around the damaged reactor buildings, letting it flow harmlessly to the sea. TEPCO plans to begin freezing the soil in March 2015. 

Grid-connected Electric Buses Could Displace Diesels

Anyone who has taken a school bus is familiar with the crunching sound of an idling diesel engine—and the nasty exhaust they give off. Researchers at the University of Delaware argue that cleaner electric school buses can make financial sense for school districts if they provide services to grid operators.

In an economic analysis published in Applied Energy and announced yesterday, researchers found that switching over to a fleet of electric buses, each of which costs more than twice a diesel bus, could save a school $38 million over at typical 14-year lifespan. “It would be cheaper to operate these buses,” said Jeremy Firestone, director of the Center for Carbon-free Power Integration at the University of Delaware. “And kids don’t need to be exposed to diesel fumes.” 

The University of Delaware has an ongoing experiment that's at the leading edge of vehicle-to-grid technology. It has 15 electric Mini Cooper sedans that earn money by providing quick bursts of power—as short as a few seconds or as long as several minutes--to balance the local electric grid. The cars’ batteries effectively act as a mini power plant, providing frequency regulation services that are normally provided by fossil fuel plants or very large stationary batteries.

Electric school buses could provide the same services and, in some ways, are better suited for the task than consumer-owned plug-in cars. Because electric buses are only used for short periods of time, their batteries are typically available for many hours of the day, which makes them more valuable to the local grid operator that would purchase frequency regulation services. Also, fleet owners are more likely to invest in the inverter and control hardware to create two-way connection to the grid.

The shorter range of an electric bus compared to a diesel bus is not going to be a problem for most urban and suburban school districts, said Firestone. Regenerative braking from frequent stops can aid battery range as well.

The analysis included the medical and climate benefits of using an electric bus. Even when they were not included, a vehicle-to-grid-capable electric bus could save a school district more than $5,700 per seat over its life, according to lead author Lance Noel.

Diesel exhaust, which contains benzene and soot, is classified as a probable human carcinogen by many government agencies, including the International Agency for Research on Cancer and the US Environmental Protection Agency. And children are particularly susceptible to the adverse respiratory effects from fine particular matter, according to the nonprofit Environment and Human Health. It's estimated that 0.3 percent of in-cabin air comes from the bus's exhaust, the University of Delaware paper notes.

Practically speaking, many school districts will be unwilling or unable to pay more for electric buses. In its test, the University of Delaware ran its analysis with a bus that costs $260,000, compared to $110,000 for an equivalent diesel.

Firestone speculated that parents could be motivated by the health benefits of an electric bus to press school districts to pay the higher upfront costs. Also, a third-party fleet operator could own the buses and earn money from the frequency regulation grid services. Third-party ownership of rooftop solar panels has helped fuel rapid growth of distributed solar in the U.S. States and the federal government could also provide financing for first-of-a-kind vehicle-to-grid projects, Firestone said.

Another variable in vehicle-to-grid technology is the local grid operator. The University of Delaware is earning money with its fleet of electric Mini Coopers with PJM, which is a large and progressive grid operator. PJM makes relatively large frequency regulation payments and pays more for fast-acting energy resources, such as batteries, which has helped enable a number of innovative applications. For example, the Philadelphia subway authority has been able to finance an energy storage system that captures energy from braking trains and provides balancing services to the local grid.

Firestone is hopeful that school districts will consider electric buses when they need to upgrade. "Once you have the first couple installed and people understand both the economic and health benefits, it's an idea that could catch on rather quickly," he said.

EPA Set to Unveil Climate Proposal for Existing Power Plants

Next week, the U.S. Environmental Protection Agency (EPA) will unveil its climate rule for existing power plants. The details of the plan have not been released, but they will require reductions in carbon emissions although states will have flexibility in how they make those cuts, according to news reports.

The proposal will likely create regional carbon-trading programs, according to The Washington Post. No matter what the details, there will likely be a challenge from utilities, especially those that rely heavily on coal-fired power plants for generation. Utilities are responsible for about one-third of greenhouse gas emissions in the United States.

Rather than each power plant having to meet the requirement, EPA would require states to meet the overall target. In that case, utilities could meet the requirements by cutting emissions at an individual plant, or could finance energy efficiency on the demand side.

"I cannot see a credible resolution to our climate change challenges without an enormous contribution from the demand side of the equation. The efficiency side is going to have to drive our strong response," U.S. Department of Energy Secretary Moniz, said recently at the 2014 Energy Efficiency Global Forum, according to Greentech Media. The new rules are part of Obama's climate action plan, which was first announced last summer. 

The proposal could look like renewable portfolio standards (RPS), according to The Washington Post, which require a certain percentage of electricity to come from non-fossil generation. So the 30-plus states that already have an RPS might find it easier to meet existing goals.

Various energy producers are already lining up for a fight. Wind producers and nuclear companies, such as Exelon, are in support of stricter carbon standards. “We think the reality is in the absence of carbon policy, it’s going to be difficult to keep the existing [base] of clean energy in service,” Joe Dominguez, Exelon’s senior vice president of governmental, regulatory affairs, and public policy, told The Washington Post.

On the other side, coal-heavy states such as Kansas, rural electric cooperatives, and some power producers are ready to fight the measures, as they have with EPA’s regulations for carbon emissions for new coal and gas-fired power plants

Depending on the details released next week, there could be many technologies that win. If there is wide-ranging flexibility for states to meet the reductions, energy efficiency measures could be one of the biggest winners.

A Natural Resources Defense Council (NRDC) proposal on how to cut carbon pollution is seen as one of the models for the standards EPA will adopt. NRDC’s proposal [pdf] calls for energy efficiency to be the primary means for reducing carbon. State-regulated energy efficiency programs could earn credits for avoided pollution and generators could purchase and use those credits towards meeting compliance. One issue with a focus on efficiency will be having standardized measurement and verification schemes to ensure the savings are being realized.

One technology that won’t necessarily win out if EPA is successful in regulating carbon emissions from existing power plants is carbon capture and storage (CCS) for coal-fired power plants. In Europe, which has decarbonization policies, there has yet to be commercial-scale, affordable CCS. Vattenfall, one of Europe’s largest energy producers, recently announced it was discontinuing its CCS research.

In the United States, coal is already on the decline, new EPA regulations on climate notwithstanding. Earlier this year, the U.S. Energy Information Administration increased its prediction for coal retirements from 40 to 60 gigawatts by 2016, mostly driven by the EPA’s Mercury and Air Toxics Standards and low natural gas prices. So far, the loss of capacity has been replaced by upgraded transmission, energy efficiency, and some renewables.

The EPA rule for existing power plants is expected to be finalized in June 2015.

New Battery Tech Could Turn Waste Heat to Electricity

Every year, Lawrence Livermore National Laboratory in California publishes an amazing chart cataloguing all the energy used in the United States. The striking thing about it is the "rejected energy" portion of the chart: in 2013, more than 60 percent of our 97.4 quads (around 293 billion kilowatt-hours) of energy were rejected, or wasted. Most of that dissipates as heat: from smokestacks and manufacturing processes, and from your tailpipe. Capturing some of that heat has long been a dream that would improve our efficiency and reduce energy use and emissions, and new research takes a novel approach to achieve it.

Most waste heat ideas involve the thermoelectric effect, where a voltage is created based on a temperature difference. This approach has been limited by materials and the need for very high temperatures and gradients, but the new idea, using the thermogalvanic effect can operate at much lower temperature differences. The researchers responsible for this idea, from Stanford and MIT, describe thermogalvanics as "the dependence of electrode potential on temperature."

Basically, it works like this: an uncharged battery is heated by waste heat (from, say, some manufacturing process in a factory), and then it is charged. The battery is then allowed to cool, and discharges only at a cooler temperature. The charging voltage is lower at higher temperatures, meaning the charging voltage is lower than the discharging voltage; that means more energy can be extracted via discharge than was inputed via charging. The extra energy comes from the heat differential.

They aim to use this type of system at temperatures below 100°C; in tests, at 60°C they achieved a conversion efficiency of 5.7 percent. The battery used in the tests consisted of a copper hexacyanoferrate cathode and a Cu/Cu2+ anode.

One investigator, Yi Cui of Stanford University, said in a press release that the potential for this idea is enormous. "Virtually all power plants and manufacturing processes, like steelmaking and refining, release tremendous amounts of low-grade heat to ambient temperatures. Our new battery technology is designed to take advantage of this temperature gradient at the industrial scale."

To be sure, though, they are far from actually sending these batteries to a steel mill to capture a bunch of lost energy. It has a much lower power density than thermoelectric devices, meaning huge versions of this battery might be required to deliver enough power. And charging and discharging probably needs to be sped up substantially before the technology becomes viable as well. But with wasted energy pouring out of every smokestack in the world, this idea isn't likely to dissipate any time soon.

Iron-Chromium Flow Battery Aims to Replace Gas Plants

Photo: EnerVault

The four round structures pictured above may look like grain silos but they're actually giant flow batteries. They're part of a demonstration plant going online this week, and proponents say it could represent the future of long-duration energy storage on the electric grid.

Startup EnerVault will unveil tomorrow what it says is the largest iron-chromium flow battery ever made. Installed in Turlock, Calif., the four-hour, 250-kilowatt battery will be charged by a solar array and power an irrigation system. The project was funded by about US $5 million from Department of Energy through the stimulus program and the California Energy Commission.

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Airbus’s E-Fan Electric Plane Takes Flight

The Airbus E-Fan took its first public test flight last month, making it the latest in a group of all-electric aircraft to take to the sky.

The flight was not just a media stunt. Airbus Group hopes to eventually develop a hybrid-electric regional plane that could seat 70 to 90 people, according to a report in Reuters. Developing such an aircraft, however, could take up to 20 years.

In the more near, term, Airbus sees a future for its E-Fan test plane. The composite, two-seater training aircraft is equipped with two lithium-ion polymer batteries (250 volts total) from KOKAM, a leading advanced battery maker, that are housed in the wings. The batteries provide 60 kilowatts of power to the plane's electric motors. The motors drive a variable pitch fan. The plane can fly for up to about 45 minutes, but Airbus says it can eventually get that flying time closer to an hour and 15 minutes.  

There are various electric aircraft prototypes across the world, but the difference is that Airbus is one of the world’s leaders in commercial aircraft manufacturing. (Check out 10 Electric Planes to Watch). While the A380 isn't going to go electric anytime soon, any breakthroughs that Airbus develops in electric-powered planes could reverberate through its business. 

Unlike some other electric aircraft, Airbus says that the E-Fan was built from the ground up to be electric rather than being based on existing fuel-powered airframes. For example, the landing gear is integrated into the fuselage for low drag, and the energy management and safety features were designed to be driven by electrical propulsion. There is a backup battery for emergency landing.

At the same time, the E-Fan needs to have flight parameters that are similar to existing training aircraft if it’s going to be used as a test plane. Ultimately, Airbus wants to construct a fleet of E-Fans and manufacture them close to the Bordeaux Airport in France. Production could start as early as 2017, according to Reuters.

Because the aircraft runs on electric motors, it emits no carbon dioxide during the flight and vibrates far less than a comparable fossil-fuel-powered plane. It is also quieter during take off and landing, which should be a benefit to communities surrounding test flight areas.

The investment in electric flight is spurred in part by the European Commission’s “Flightpath 2050” [PDF] which calls for a 75-percent reduction in aircraft CO2 emissions, a 90-percent drop in nitrous oxide emissions, and a 65-percent cut in noise levels compared with the respective numbers from the year 2000.

“It will not only lead to a further reduction in aircraft emissions and noise to support our environmental goals but will also lead to more economic and efficient aircraft technology in the long run,” Jean Botti, chief technical officer for Airbus Group, said in a statement.

The E-Fan will also make an appearance at the ILA Berlin and Farnborough airshows this year. Airbus has not released a projected cost for the electric plane.

UPower's Truck-Size Nuclear Power Plant

There are a number of efforts to build small modular nuclear reactors aimed at lowering the cost of nuclear power. But one company is designing a reactor that’s so small it would fit in a shipping container.

Boston-based UPower Technologies, founded by three nuclear engineers from MIT, is betting that its very small nuclear “battery” can be cost-competitive with power from diesel generators used in remote locations. It’s one of a handful of companies creating new reactor designs with the hopes of improving nuclear power’s safety and cost.

By building a very small reactor, the company thinks it can test full-scale prototypes cheaply and meet a market need for energy in remote places, such as mining operations, island nations, or military microgrids. It expects that its reactor would generate between one and two megawatts of electric power. By contrast, a full-size nuclear power plant typically produces about 1000 megawatts.  

In addition to being small, its reactor technology breaks with the dominant light water design. In today’s power plants, fuel rods held in metal assemblies are submerged in water. The heat from the core is converted into steam to turn a turbine and generate electricity. To avoid overheating in the core, water needs to be constantly circulated through it.

With UPower’s design, the nuclear reactor would be placed in a tall cylinder buried underground. Rather than remove heat from the core with water, company engineers have developed a system that’s similar in concept to steam radiators.

The reactor is equipped with a number of vertical stainless steel pipes filled with a mixture of liquid and gas. Those pipes are slotted into channels, or holes, in a metal block at the base of the reactor, explains CEO Jacob DeWitte. 

As the core produces heat, it causes the liquids at the bottom of the pipes to evaporate and rise to the top. That heat would then be converted into electricity using conventional generators. Removing the heat from these steel loops causes the gas to condense and drop to the bottom to begin the evaporation cycle again. "You don’t need pumps and it’s able to move the heat,” DeWitte says. “It’s a completely passive, self-contained phase change.”

In a light water reactor, water acts to both moderate the nuclear reaction and to transport heat from the core. With the UPower design, the steel pipes are enclosed and would only carry away heat. The nuclear fuel would also fit into channels in the metal block at the base of the reactor, DeWitte adds. He envisions using the same low-enriched uranium in conventional reactors but it could use other nuclear fuels.

The company went with this scaled-down approach for business reasons. The cost of testing a prototype of a new type of nuclear reactor costs millions of dollars, whereas DeWitte expects UPower could test its thermal management system at full size for thousands of dollars.

The reactor also seeks to improve on the safety of current plants. In the Fukushima disaster three years ago in Japan, a loss of back-up power to run water pumps caused the cores to overheat and melt down. With the UPower design, the heat would dissipate through a separate set of horizontal cooling loops that would transfer heat to the ground through natural convection, DeWitte says.

A number of countries, including China, Russia, and South Korea, are building new nuclear power plants. But in the United States, nuclear power is more expensive than building a new natural gas plant. UPower’s strategy is to target locations that pay high costs for energy because they need to import diesel fuel. Its reactors could supply both heat and electricity at lower costs, DeWitte says.

The company is one of a handful of nuclear startups that are hoping to bring advanced reactors to market. Among them are Bill Gates-backed TerraPower, Transatomic Power, and a few companies pursuing nuclear fusion, including General Fusion, Helion Energy, and TriAlpha Energy. There are also a number of efforts to build small modular reactors, which are light water reactors designed to be simpler to build and install than full-size plants.

By working through a startup, rather than a national lab, entrepreneurs hope to move quickly and commercialize new nuclear technology But the process of obtaining a license to operate advanced reactors will likely take many years, says Jessica Lovering, a nuclear policy analyst at think tank the Breakthrough Institute. “All the regulations and applications are very focused on the light water designs,” she says. “The whole fuel cycle is optimized for it.”

DeWitte is hopeful that the company can test its basic design by the end of next year and start the licensing process. There’s a demand for alternatives to diesel generators in remote locations and strong commercial interest could help speed up the approval process, he says. 

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