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India Plans to Install 26 Million Solar-powered Water Pumps

India’s government wants to replace 26 million groundwater pumps for irrigation with more efficient pumps that run on solar power, in an effort to relieve farmers of high costs of diesel fuel. Diesel generators are commonly used when grid power is unavailable, a not uncommon occurrence. And the power used for pumping irrigation water is also one of the largest strains on the Indian power grid.

The initiative is expected to require $US 1.6 billion in investment in the next five years just to switch out the first 200 000 pumps, according to Bloomberg.

Pumping water is critical for Indian agriculture, which otherwise relies on seasonal rain. It's also very contentious—Indian farmers are currently drawing more water than is sustainable, removing about 212 million megaliters from the ground each year to irrigate about 35 million hectares.

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Liquefied Air to Store Energy on U.K. Grid

When it comes to storing energy on the grid, giant batteries are the only game in town. Now, a number of companies are building mechanical systems that use air as the storage medium.

U.K.-based Highview Power Storage last week said that it has been awarded an £8 million grant from the U.K. Department of Energy and Climate Change to build a commercial-scale facility that uses liquified air to store energy. Highview is already running a smaller pilot plant, but the full-scale version will be able to store enough energy to deliver five megawatts of power for three hours. That puts it on a scale that would entice utilities to use the technology, says company CEO Gareth Brett.

"We're treating this (demonstration plant) as a shop window on the technology," he says. "Utility companies are pretty conservative and they want to see this bit of kit working at a scale that they can buy one."

Liquid air energy storage is similar to compressed air energy storage in that air is compressed and released to store and then generate power. With Highview’s technology, though, ambient air is compressed, then cooled and liquified. That liquefied air, which is almost -200 °C, is stored in large tanks.

When power is needed, the liquid air is released and pumped to high pressure. That causes the liquid to evaporate, turning it into a high-pressure gas which is then run through a turbine to generate power. The planned demonstration plant will be located at a waste processing center. Heat from the waste plant’s gas turbines, which run on captured landfill methane, will be piped in to improve the efficiency of the evaporation process.

One of the advantages of liquid air storage is that it uses off-the-shelf equipment. The tanks for storing liquid air, for instance, are the same as those used in the industrial gas industry. Highview’s expertise is in engineering the different components into a working system with the highest possible efficiency. “Getting the supply chain right is really what our technology is all about. What we’re trying to do is get a system to work with widely available kit,” Brett says.

This commercial-scale plant also gives an indication of how much liquid-air energy storage costs. For 15 megawatt-hours of storage, it will cost about £533 (about $900) per kilowatt-hour. But Brett projects the economies of scale from a larger plant would allow Brightview to get the cost under $500 per kilowatt-hour. At that price, energy storage on the grid can be cost competitive with power plants for a number of applications, such as storing wind and solar energy for delivery during peak hours, say experts.

Highview’s plant will be used to relieve congestion on the grid. For example, stored energy can supply power to the local distribution grid when substations are maxed out during peak hours.

The U.K. has emerged as a leader in advancing liquid air storage technologies. Last year, the Center for Low Carbon Futures released a report that identified liquefied air and liquid nitrogen as a valuable “vector” of research for storing energy for both the grid and transportation. And last year, the University of Birmingham won a £6 million grant from the U.K. government to establish a Center for Cryogenic Energy Storage.

Although liquid-air energy storage is a relative novelty in the utility industry, storing energy in the form of compressed air has a long track record. Two compressed air plants—one in Huntorf, Germany, and one in Alabama in the United States—have been operating for decades. Though the technology is considered reliable and relatively low-cost, these two plants use underground caverns to store pressurized air.

A few companies are now developing systems to store compressed air in above-ground tanks or pipelines, which makes siting easier. Because liquefied air is stored in tanks, Highview facilities can also be located in a wide range of industrial sites, Brett says. And because liquid air is four times as dense as compressed air, its tanks take up less space than those holding compressed air; liquid-air storage is also cheaper because the medium can be contained in less-expensive, low-pressure tanks, Brett says.

Still, Highview Power faces a number of competitors, including many battery makers that hope to slash the cost of storage. One of the biggest advantages Highview has is its potential to scale up quickly. Because it’s using off-the-shelf equipment, it doesn’t need to build a new plant or develop new manufacturing methods as new battery companies may need to. In theory, that means, if it has the orders, it can build and engineer storage plants without having to invest in its own production facilities.

Its large-scale demonstration site is projected to go online next year and, if utilities like what they see, the technology’s next step is a commercial plant.

Image: Highview Power Storage

Nearly Half of U.S. Power Plants Don’t Reuse Water

In the past half century, power plants in the United States have made considerable strides in water use, but there is still a long way to go, according to new figures from the U.S. Energy Information Administration (EIA).

More than 70 percent of electricity in the United States comes from plants that require some water for cooling. Most plants that generate steam to make electricity use water to re-condense the steam for reuse. While many plants return that water to the environment, others use less water but lose that water to evaporation in the cooling process. In total, it’s a huge demand on fresh water supplies: More than 40 percent of fresh water used in the United States is withdrawn to cool power plants.

Originally plants were once-through systems, where the water was only used once and then put back into the ecosystem. 

But other cooling techniques have been adopted in newer plants, though perhaps not fast enough given ongoing drought conditions. Because of environmental standards, most new plants use recirculating water systems and, to a lesser extent, dry cooling. The trend towards recirculating plants began in the 1960s, but the long lead-time on the switch over still means that many power plants still in use are once-through water systems. In the United States, 43 percent of plants do not reuse water, according to the EIA.

 

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Richard Branson Wants Caribbean Islands to Swap Diesel for Renewables

Dirty diesel is the most common form of electricity generation throughout Caribbean island nations, but that will change if billionaire Richard Branson has anything to do with it.

Branson is using his private island in the British Virgin Islands, Necker Island, as a test bed for a microgrid that will run on renewable generation. The project on Necker, which is supported by NRG Energy, is not just an exercise in bringing renewables to the region at any cost. It aims to make renewables affordable to island economies.

“What we’ve learned in the renewable world is everyone wants to save the world,” David Crane, NRG’s chief executive, told The New York Times. “But very few people want to pay more for energy.” The average price of electricity in the Caribbean is about four times higher than it is in the mainland United States.

The push for clean energy is the core mission of the Ten Island Renewable Challenge led by the Carbon War Room, a nonprofit founded by Branson. The problem for most islands is that the upfront cost of renewable technology and storage is relatively expensive given that most island nations have small populations. Because the projects are relatively small, compared to projects in the US or Europe, it can be difficult to get financing. 

At the same time, however, islands across the globe depend on diesel, which makes electricity incredibly expensive compared to regions that rely on other fossil fuels such as coal or natural gas. Hawaii, for example, has the highest electricity rates in the United States, about double the price of the next closest state.

Branson's challenge in the Caribbean already has the support of Aruba, British Virgin Islands, St. Lucia, and Turks and Caicos. Aruba, for example, already has a wind farm and is planning more.

Other islands are looking at solar, wind, LED lighting for municipal applications, waste-to-energy, and geothermal. For years, Barbados has been toying with the idea of using a special breed of sugar cane for co-generation, but has yet to invest in a large-scale project. Late last year, Puerto Rico mandated energy storage to go with wind and solar projects on the island, which could be a model for other islands if it is successful.

On the 74-acre Necker Island, the microgrid will combine wind, solar, and batteries that can support about 80 percent of the island’s energy requirements. On small islands, like Necker, microgrids may seem like a natural solution, but cost remains an issue if they are powered by renewables.

Although the cost of renewables have come down, and might be competitive with expensive diesel power, intermittent renewable energy requires expensive storage and sophisticated controls to balance grid conditions on that small of a scale.

Branson has the will and the deep pockets to invest in such a project, but the results will have to be replicable at a price that non-billionaire utility customers can afford on other islands.

Some of the solutions may be in attractive financing, rather than in proving the technology. In some places, subsidies for diesel make it more affordable and if those are ended, renewables look more attractive. Short-term tax benefits for renewables can also help to get projects off the ground. The Carbon War Room said it would help islands with assistance in attracting project engineers and financiers.

“There’s tens of thousands of islands burning diesel fuel that’s really destroying their economies because it’s so expensive,” Crane told the The New York Times.

Branson is hoping for quick results, and not just on Necker Island. "We're hoping to get a number of islands to sign up to get as carbon-neutral as they can over the next few years," Branson told Phys.org. “Immediately afterwards,” he wrote in a blog post, “we want to head to the Pacific Islands and implement everything we will have learned.”

 

Photo: Todd Vansickle/AP Photo 

Bio-Energy Box Coverts Beer Waste to Electricity

People have long known there is energy in wastewater; extracting it economically is the problem. Startup Cambrian Innovation claims its technology can do it and a brewery and a winery are now using it to clean their wastewater while producing energy.

The company's EcoVolt machine is a shipping container-size reactor that uses microbes to convert dissolved carbon in industrial wastewater into biogas, which can be burned on site for electricity or heat. Its first demonstration unit is running at the Clos du Bois winery in Sonoma county, and last month nearby Bear Republic Brewery in Cloverdale, Calif. flipped the switch on the second system.

Typically, food and beverage businesses remove the organic material in wastewater—measured as biological oxygen demand (BOD)—by aerating water with pumps. But that can be an energy-intensive process. The Bear Republic Brewery expects it will be able to eliminate 80 percent to 90 percent of the BOD of its wastewater with the EcoVolt and reuse 10 percent of its water. By burning the biogas, the brewery thinks it can cover 50 percent of its electricity needs.

The return on investment for the brewery is about four years in reduced energy costs, says Cambrian Innovation CEO Matthew Silver who I spoke to at the company’s headquarters in South Boston. Silver had planned to work in aerospace but became fascinated by advances in biotech and genetic engineering while a research scientist at MIT. Under a NASA grant, he led research into how bioelectric systems could be used to manage water in space. In doing that, he saw the potential for using electrochemically active microbes to clean water in industry. There's plenty of need: About three percent of the U.S. electricity is consumed treating wastewater, and producing one bottle of beer typically results in up to ten times as much in wastewater.

Making biogas from waste has been done for years and is not necessarily high tech. Industrial anaerobic digesters, which often look like farm silos, use naturally occurring bacteria to consume organic material to make biogas, which is siphoned off.

Cambrian Innovation's EcoVolt achieves a similar result but with a different anaerobic process. Its reactor has microbes that consume organic matter as food and deposit electrons directly on a metal electrode. Found in soil, these microbes, sometimes called exoelectrogens or anode-respiring bacteria, are the active component in some types of microbial fuel cells.

The EcoVolt system uses these microbes to produce a flow of electrons from a bacterial-film-covered anode to a cathode. They do this by breaking down organic molecules into hydrogen and carbon dioxide. At the cathode, another set of microbes, with the aid of the electric current, convert the CO2 and hydrogen from the first reaction to methane. A byproduct of that reaction is clean water.

The company is also working on a microbial fuel cell under a Department of Defense contract, which is part of US $8 million Cambrian Innovation has secured in DoD and National Science Foundation grants. The plan is to make a self-powered wastewater treatment facility for operating bases or for off-grid applications in the developing world.

CEO Silver has confidence that it can make an economic microbial fuel cell, but decided to target its first commercial product on the wastewater industry. By taking advantages of advances in other fields of engineering, the company was able to design a product that has compelling economics, he says. "We realized we needed to combine the advantages of biological systems with electrochemistry and information technology and really create a package," says Silver. It's now targeting companies in the food and beverage industry and seeking applications in other industries.

One of the advantages of the EcoVolt over traditional anaerobic processes is that it can be remotely monitored in real time. By viewing the rate and the health of reactions on the electrodes, Cambrian Innovation engineers can adjust flow rates and other bioreactor parameters. That’s much quicker control than a typical anaerobic reactor, which requires taking a sample and doing tests, says company chief technology officer Justin Buck. Company engineers have also developed techniques to adjust the reactor’s biology, which allows the EcoVolt to be robust and work with different types of waste streams, he adds. “We make sure that the proper community of microbes gets established on these electrodes,” he says. “If we don’t do that, incoming water will bring in new microbes, which is essentially a source of contamination.”

There are several reseachers and companies trying to take advantage of microbes to make electricity from wastewater. A group at Penn State, for example, combined a microbial fuel cell with reverse electrodialysis, a way to capture energy from a difference in water salinity, in an effort to increase electricity output.

Israeli company Emefcy (a play on the acronym for microbial fuel cell) has engineered a microbial fuel cell optimized for municipal wastewater. Another wastewater-to-energy startup is Arizona State University spin-off, Arbsource, an Arizona State University spin-off, uses anode-respiring bacteria to produce electricity, as Cambrian Innovation does, as well as hydrogen, ammonia, and other chemicals. And a number of municipalities produce biogas with digesters and use it to generate electricity and heat through fuel cells.

By contrast, the EcoVolt system is designed specifically for wastewater reuse. Cambrian Innovation hopes to appeal to businesses with high energy costs from wastewater treatment and, in general, bring more innovation to the slow-moving and conservative world of water treatment. "Up until now, compliance (with water treatment regulations) was viewed as a cost of doing business and a big part of the industry is designed around avoiding liability,” he says. “Now wastewater can be a source of revenue.” 

Image credit: Cambrian Innovation

Lasers Can Remotely Monitor Oscillations of Wind Turbines

Wind turbines, like any machine with moving parts, can fail. They have a useful life span, after which the loading on the various pieces including turbine blades and tower could cause decreases in efficiency or, in very rare cases, outright collapse. That loading comes during normal operation, but the oscillations the turbine undergoes play an important role in just how long a turbine will survive. Heretofore, sensors placed physically on the turbine have been the method of choice for measuring the oscillations. But lasers might work better.

A new system, to be demonstrated at an IT conference called CeBIT in Hanover, Germany, in March, combines a low-power laser with a camera to comprehensively assess oscillations of a wind turbine. Unlike the sensors-on-the-turbine technique, with which the oscillations are really only recorded at the specific points where the sensors sit, the laser-based method captures the entire oscillatory pattern—on the blades, tower, all of it—and paints a more complete picture.

Researchers at the Fraunhofer Institute in Germany created the new system. From a press release:

"The centerpiece of the system responsible for this is an IT-based tracking system combining a camera and a laser. These are mounted on a head that can pan and tilt to follow the rotor blades. The camera records images of the installation and forwards these along to software that processes the images and builds a model of the rotary motion from the data. With the help of this information, the pan and tilt head is positioned so that the laser automatically follows the rotor blades. The camera simultaneously collects data about the exact position of the roughly two-to-three centimeter laser spot on the rotor blade in order to stabilize it on the revolving surface."

The researchers, led by Ilja Kaufmann, say that the system is easily transportable, and can work from hundreds of meters away from the turbine itself. Assuming it's possible to correct for the laser's motion, even monitoring offshore turbines from a boat should be feasible. As many wind farms near the ends of their prescribed operating lives, systems like this can help operators make choices regarding when to decommission a turbine. "Operators can use our technology to [evaluate] their installations," Kauffman said. "We can provide decision-making assistance for questions like 'Is it in good enough shape that I can continue to operate it, or should I sell it and build a new one at the same site?'"

This idea seems to solve a few issues with turbine monitoring: keeping track of the full turbine rather than just individual points, and making the process easier. The new tool and technique make it simple to monitor one turbine, move the system to the next one, and so on. And it seems that idea is gaining steam: below is a video of another method for remotely monitoring a wind turbine using interferometric radar from up to a kilometer away. The days of sensors on turbine blades may be on the way out.

Attack on California Substation Fuels Grid Security Debate

When at least one sniper attacked a substation in California last April, the power did not go out. But the incident did bring the issue of power grid security to a new level.

New reports about an attack on Pacific Gas & Electric’s (PG&E) substation in California last April raise questions about the vulnerabilities of the U.S. power grid. The Metcalf transmission substation was not a critical facility, but the Wall St. Journal speculated that the attack could have been a test ground for a larger attack.

The former Federal Regulatory Commissioner, Jon Wellinghoff, told the Wall St. Journal it was "the most significant incident of domestic terrorism involving the grid that has ever occurred" in the U.S.

The assault took place in the middle of the night when at least one person entered an underground vault at PG&E’s Metcalf substation and cut fiber cables. Soon after, one or more gunmen opened fire on the substation for nearly 20 minutes. They took out 17 transformers and then slipped away into the night before police showed up.

Despite the coordination, tossing around the word terrorism might be premature. The attack appeared planned, but for now, the Federal Bureau of Investigation doesn’t think a terrorist organization is involved.

No matter who carried out the attack, there are questions about how to balance investment against attacks both physical and cyber. Foreign Policy magazine reported that Wellinghoff has noted that the recent focus on cybersecurity has overshadowed the need to rethink physical security.

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India Aims High With 4-Gigawatt Solar Plant

The fourth-largest energy consumer in the world is starting to make some noise on the renewables front. India, with its growing population and GDP, has announced plans to build a massive 4-gigawatt solar photovoltaic plant near Sambhar Lake, west of Jaipur in the state of Rajasthan. This would dwarf all existing PV plants around the world, and would nearly triple India's existing solar generating capacity in one fell swoop.

Nature reports that the mega-project will cost $US 4.4 billion, and will take seven years to complete. The plant would go a long ways toward India's plan to have 20 GW of installed solar capacity by 2022 [PDF], up from essentially zero only a few years ago. Of course, building anything this big often means delays and cost overruns, especially in a country not known for strong electricity infrastructure. Still, it's an encouraging sign that India is trying to move beyond its historical predilection for building coal plants.

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Hybrid Generator Would Cut Military Base Fuel Costs in Half

The phrase "An army marches on its stomach," often attributed to Napoleon Bonaparte, underscores the importance of logistics in the military. And in the 21st century, keeping up the supply of diesel fuel is one of the most challenging logistical tasks for military forces in the field.

Last month, the U.S. Department of Defense (DoD) awarded a contract to a company that says its “hybrid generator” can reduce the amount of fuel used by generators at outposts by more than 50 percent. The company, Earl Energy, uses a rack of batteries coupled to diesel generators—and, if available, solar panels—to optimize fuel consumption. It’s one of a number of projects funded by the Department of Defense to reduce fuel consumption through efficiency and renewable energy.

Today, the U.S. military powers its operating bases with diesel generators that run continuously. The problem is that it’s difficult to match the generating capacity with the actual power load from air conditioners, electronics, and other gear, which fluctuates during the day and in different seasons. And when the demand for power is lower than the generator’s full capacity, the fuel efficiency drops off dramatically and the maintenance increases.

At the same time, the electricity requirements for bases in places such as Afghanistan have gone up substantially. Compared to a Marine battalion a decade ago, bases now have more than twice the number of radios and vehicles and three times the number of computers, according to the Department of Defense.

Earl Energy’s FlexGen “hybrid generator” is wired to a diesel generator running at full capacity, which is how it's most efficient. When there is excess power, the diesel generator charges the batteries. If the batteries have enough stored energy to meet the demand for electricity, then the generator shuts off. In tests in Afghanistan, the Earl Energy system allowed the generators to run three to six hours a day, compared with around the clock before it was installed, says Doug Moorehead, the CEO of Earl Energy.

A former Navy Seal, Moorehead saw first hand the perils of transporting fuel while stationed in Iraq. Fuel and water convoys are frequent targets. For example, in one three-month period in 2010, six marines were wounded during convoys (a rate of one injury for every 50 convoys). The financial cost is great as well; fuel can cost $2.64 to $3.96 per liter ($10-$15 per gallon) by the time fuel is delivered to outposts, says Moorehead. "If you reduce the fuel consumption, you can now cut [the number of fuel convoys] in half,” he says.

After Moorehead’s time in the Navy, the MIT graduate attended Harvard Business School and then went to work at lithium-ion battery company A123 Systems, where he worked in the grid energy storage group.

With funding from a previous Department of Defense program, Earl Energy was able to build prototypes for its energy storage device. It now has about a dozen units in the field, which are partially charged with energy generated by solar panels. The system’s control software can be used to manage multiple generators in order to create a base-wide microgrid.

The contract Earl got last month under the Mobile Electric Hybrid Power Systems (MEHPS) program is for delivery of products that conform to the Department of Defense's specifications and could lead to purchase of about 50 units, says Moorehead. "It shows that the DoD is very serious about hybrid generators," he says. (Another company, UEC Electronics, was also awarded a contract to build a generator that fits on a trailer and combines energy storage and solar power.)

Last fall, Earl Energy won another contract from the Army Communications-Electronics Research, Development and Engineering Center (CERDEC) to design power converters based on silicon carbide. "All existing power electronics are silicon-based but the next generation uses silicon carbide, which allows for much higher voltages and conversion efficiencies,” Moorehead says. The company expects its power converters, which will be used with its generators by the middle of next year, to be 80 percent lighter and 70 percent smaller than existing models.

Outside of the military, there is growing interest in distributed power generation, both in grid-connected and off-grid scenarios. Concerned that severe storms will knock out power for long periods, businesses and institutions such hospitals and universities are looking at on-site power generation with natural gas and solar. Meanwhile, microgrids can bring power to places in the world where there is not a reliable centralized grid, whether it’s remote parts of Alaska or rural villages in developing countries.  

Indeed, Earl Energy has ambitions beyond the military. This spring, it will begin testing a hybrid generator at a drill rig in Texas. This installation will use a design similar to the FlexGen hybrid generator, but it will include fast-acting ultracapacitors instead of lithium-ion batteries connected to a 1.2 megawatt generator. Oil and gas drillers typically use very large diesel generators, but drillers are looking for ways to use natural gas that is available from wells to save money and reduce emissions from their operations, Moorehead says.

Image credit: Earl Energy

EC Sees Heavy Pricetag to UK Nukes Plan

Government incentives for a pair of proposed nuclear reactors could cost U.K. taxpayers as much as £17.62 billion, thus exceeding the reactors' projected cost. The EC figure is a preliminary estimate included in an initial report to London published on Friday by European Commission competition czars. The letter notifies the British government that—as we predicted in December—Brussels is launching a formal investigation to assess whether the subsidies violate European state aid rules. 

The preliminary findings suggest that the U.K. and E.C. are on a collision source. As the Financial Times summed it up this weekend: "The severity of [the EC's] initial concerns will cast a shadow over government hopes to win approval for the deal."

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