Power Generation

[Due to the increasing size of the archives, each topic page now contains only the prior 365 days of content. Access to older stories is now solely through the Monthly Archive pages or the site search function.]

New lithium polysulfide flow battery for large-scale energy storage

April 25, 2013

Stanford / SLAC’s new lithium-polysulfide flow battery design compared to conventional “redox” flow batteries. The new flow battery uses only one tank and pump and uses a simple coating instead of an expensive membrane to separate the anode and cathode. (Credit: Greg Stewart/SLAC). Click to enlarge.

Researchers from the US Department of Energy’s (DOE) SLAC National Accelerator Laboratory and Stanford University have designed a new lithium/polysulfide (Li/PS) semi-liquid (flow) battery for large-scale energy storage, with lithium polysulfide (Li₂S₈) in ether solvent as a catholyte and metallic lithium as an anode.

Unlike previous work on Li/S batteries with discharge products such as solid state Li₂S₂ and Li₂S, the catholyte is designed to cycle only in the range between sulfur and Li₂S₄. Consequently, the team points out in a paper describing there work published in the RSC journal Energy & Environmental Science, all detrimental effects due to the formation and volume expansion of solid Li₂S₂/Li₂S are avoided.

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German researchers improve catalyst for steam reforming of methanol with salt coating; enabler for renewable energy storage systems

April 19, 2013

Researchers at the University of Erlangen-Nürnberg (Germany) report in the journal Angewandte Chemie their development of an enhanced platinum catalyst for the steam reforming of methanol to release hydrogen.

A central problem of renewable energy technology lies in the great variation of energy generated (i.e., intermittency). One proposed solution is methanol-based hydrogen storage. In this scenario, excess renewable electricity can be used to electrolyze water to produce hydrogen. The hydrogen, in turn, is then reacted with carbon dioxide to make methanol and water, thus allowing it to be stored as a liquid. The hydrogen can be released from the methanol at a later time to power a fuel cell.

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PNNL solar thermochemical reaction system can reduce fuel consumption in natural gas power plants by about 20%; future potential for transportation fuels

April 11, 2013

PNNL’s thermochemical conversion device is installed in front of a concentrating solar power dish. Photo: PNNL. Click to enlarge.

A new concentrating solar power system developed by Pacific Northwest National Laboratory (PNNL) can reduce the fuel consumption of a modified natural-gas combined-cycle (NGCC) power plant by about 20%. The system converts natural gas into syngas—with higher energy content than natural gas—using a thermochemical conversion device installed in front of a concentrating solar power dish. The power plant then combusts the more energy dense syngas to produce electricity.

PNNL’s system uses a mirrored parabolic dish to direct sunbeams to a central point, where the thermochemical device uses the solar heat to produce syngas form natural gas. About four feet long and two feet wide, the device contains a chemical reactor and several heat exchangers. Concentrated sunlight heats up the natural gas flowing through the reactor’s channels, which hold a catalyst that helps turn natural gas into syngas.

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NSF to award up to $13M for fundamental work on sustainable production of electricity and transportation fuels

April 07, 2013

The US National Science Foundation (NSF) has issued a grants opportunity notice (PD-14-7644) for up to about $13 million in awards to fundamental research and education that will enable innovative processes for the sustainable production of electricity and transportation fuels. Processes for sustainable energy production must be environmentally benign, reduce greenhouse gas production, and utilize renewable resources.

The duration of unsolicited awards is typically three years. The average annual award size for the program is $100,000. Proposals requesting a substantially higher amount than this, without prior consultation with the Program Director, may be returned without review. Current interest areas in sustainable energy technologies are as follows:

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Hansen paper emphasizes importance of retention and expansion of nuclear power for health and climate reasons

April 04, 2013

Mean number of deaths prevented annually by nuclear power, 1971-2009. Credit: ACS, Hansen et al. Click to enlarge.

A new study by James Hansen and Pushker Kharecha from the NASA Goddard Institute for Space Studies and Columbia University Earth Institute has found that global nuclear power has prevented an average of 1.84 million air pollution-related deaths and 64 gigatonnes of CO₂-equivalent (GtCO₂-eq) greenhouse gas (GHG) emissions that would have resulted from fossil fuel burning. The estimated human deaths caused by nuclear power from 1971 to 2009 were far lower than the avoided deaths: 4,900, or about 370 times lower than the result for avoided deaths.

Projecting ahead, on the basis of global projection data that takes into account the effects of the Fukushima accident, Hansen and Kharecha also calculated that nuclear power could additionally prevent an average of 420,000−7.04 million deaths and 80−240 GtCO₂-eq emissions due to fossil fuels by mid-century, depending on which fuel it replaces. Large-scale expansion of unconstrained natural gas use would not mitigate the climate problem and would cause far more deaths than expansion of nuclear power, according to their analysis, which is published in the ACS journal Environmental Science & Technology.

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Israel begins natural gas production from deepwater Tamar field in Eastern Mediterranean

March 31, 2013

Map showing the location of Tamar, as well as the larger Leviathan field which is entering development. Source: Noble Energy. Click to enlarge.

On Saturday, Israel’s Ministry of Energy & Water Resources reported that commercial natural gas production had begun from the deepwater Tamar field (c. 5,500 ft, 1,676 m) in the Eastern Mediterranean, 90 km (56 miles) west of Haifa. (Earlier post.)

Representing a $3.25-billion gross investment, according to operator Noble Energy (36% working interest), Tamar is entering operation 2.5 years from the sanction of the project, and four years after the discovery of the field. It uses the world’s longest subsea tieback—a 16-inch (41-cm), 93-mile (150 km) pipeline. The Tamar production platform is about 290 meters (951 ft) high and weighs (along with its subsea legs) about 34,000 tons.

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DOE to award up to $266M to small modular nuclear reactor project; targeting commercial operation around 2025

March 12, 2013

DOE selected an SMR project with the B&W mPower reactor in 2012. The nuclear core and steam generators are integrated in a single vessel. Source: B&W. Click to enlarge.

The US Department of Energy (DOE) issued a new funding opportunity announcement (DE-FOA-0000800) for up to $266 million to help US industry design and certify innovative small modular nuclear reactors (SMRs)—defined for this FOA as reactor units with nominal output of 300 megawatts electric (MWe) or less that are able to be factory fabricated and transported to the site for assembly of components and operation. With a 50% cost-share, total funding for the selected project will be around $462 million.

DOE will solicit proposals for cost-shared SMR projects that have the potential to be licensed by the Nuclear Regulatory Commission (NRC) and achieve commercial operation around 2025, while offering innovative and effective solutions for enhanced safety, operations and performance. Selected projects will span a five-year period with at least 50% provided by private industry.

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Stanford study quantifies energetic costs of grid-scale energy storage over time; current batteries the worst performers; the need to improve cycle life by 3-10x

March 10, 2013

A plot of ESOI for 7 potential grid-scale energy storage technologies. Credit: Barnhart and Benson, 2013. Click to enlarge.

A new study by Charles J. Barnhart and Sally M. Benson from Stanford University and Stanford’s Global Climate and Energy Project (GCEP) has quantified the energetic costs of 7 different grid-scale energy storage technologies over time. Using a new metric—“Energy Stored on Invested, ESOI”—they concluded that batteries were the worst performers, while compressed air energy storage (CAES) performed the best, followed by pumped hydro storage (PHS). Their results are published in the RSC journal Energy & Environmental Science.

As the percentage of electricity supply from wind and solar increases, grid operators will need to employ strategies and technologies, including energy storage, to balance supply with demand given the intermittency of the renewable supply. The Stanford study considered a future US grid where up to 80% of the electricity comes from renewables.

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NTNU study finds ships’ and spare parts’ contribution to offshore wind power lifecycle impacts has been underestimated

March 04, 2013

Reference scenario impact indicator values by eight components and nine stressor sources. Components: WT = wind turbine; Fnd = foundation; EC = electrical connections, including substation; Inst = installation; IOo = input-output, other; Mnt = Maintenance, excluding replacement parts; RP = replacement parts; EOL = end-of-life. Credit: ACS, Arvesen et al. Click to enlarge.

A new analysis by researchers at the Norwegian University of Science and Technology (NTNU) suggests that, notwithstanding significant uncertainties, previous studies have underestimated the contributions from installation and use phases—e.g., “ships and spare parts”—to the total life cycle impacts of offshore wind power. Their analysis is published in the ACS journal Environmental Science & Technology.

In the study, they developed and assessed life cycle inventories of a the proposed Havsul I offshore wind farm in Norway using a hybrid life cycle assessment (LCA) methodology. The study put special emphasis on aspects of installation, operation, and maintenance, as these stages have been given only cursory consideration in previous LCAs, they noted.

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Audi to introduce natural gas A3 Sportback g-tron at year’s end; CO2-neutral e-gas

March 01, 2013

Audi A3 Sportback g-tron. Click to enlarge.

Audi will introduce the compact A3 Sportback g-tron—which can be powered by the CO₂-neutral Audi e-gas, synthetic methane generated from eco-electricity in the Audi e-gas project (earlier post)—at the end of the year. The e-gas fuel will be produced in the power-to-gas plant in Werlte, Germany.

The five-door car consumes on average less than 3.5 kilograms per 100 km of compressed natural gas (CNG) or Audi e-gas. CO₂ tailpipe emissions are less than 95 grams per km (153 g/mile) in gas mode. When the A3 Sportback g-tron is powered by Audi e-gas, no more CO₂ is released than was chemically input in its production beforehand, creating a closed loop. When the energy required to build the e-gas facility and wind power generators is included in a comprehensive analysis, CO₂ emissions under e-Gas operation are still less than 30 grams per km (48.28 g/mile).

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DOE issues $13M funding opportunity for advanced coal gasification systems for power or fuels

February 17, 2013

The US Department of Energy (DOE) has issued a funding opportunity announcement (DE-FOA-0000784) for up to $13 million to support the development of advanced coal gasification systems. DOE anticipates making 5 awards under the FOA.

There will be three (3) Areas of Interest (AOIs) under the FOA. The first two—Coal Feed Technologies - Low-rank Coal Feed or Coal-woody Biomass Feed Technologies; and Lower-cost Oxygen Production Systems—will look to further develop and expand on concepts already included in the Gasification Systems Program that will significantly reduce gasification’s capital and operating costs. The third AOI (High Hydrogen Syngas Production) will begin exploration (through systems analysis and small-scale R&D) of novel technologies to reduce the cost of creating chemical-grade hydrogen and/or high-hydrogen syngas.

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Energy 2030 outlines steps to double US energy productivity by 2030; spend $166B a year to net savings of $327B

February 07, 2013

The Alliance Commission on National Energy Efficiency Policy released a set of recommendations—Energy 2030—designed to double US energy productivity by 2030. The Commission was created in 2012 to identify solutions for increasing US energy productivity and aid in jumpstarting the economy.

To achieve the Commission’s goal of doubling energy productivity by 2030 with currently available technology and design practices, households, businesses, and federal, state, and local governments will need to invest about an additional $166 billion a year (in real 2010 US dollars) in building improvements, energy efficient vehicles and industrial equipment, and energy saving transportation systems, according to the report. This investment would both reduce the amount of energy needed to run the American economy and the price of energy for US consumers, lowering overall energy costs by some $494 billion a year, according to the analysis.

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Honda Transmission contracts with Juhl Wind for two utility-scale wind turbines at Ohio plant; up to 10% of electricity for operations

January 25, 2013

Honda Transmission Mfg. of America, Inc. announced an agreement with Juhl Wind, Inc. to develop, install, and operate two utility-scale wind turbines (each rated at about 2MW) to generate electricity for the plant’s operations.

The plant manufactures automatic transmissions, gears and four-wheel-drive systems, including the next-generation Earth Dreams transmission technology. The two wind turbines will supply up to approximately 10% of the plant’s electricity. Based on their location and actual wind speeds, combined output from the two wind turbines is estimated at 10,000-megawatt hours (MWh) per year.

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Volkswagen inaugurates 9.5 MW solar park at Chattanooga plant in US; key element of VW Group’s strategic sustainability targets

January 24, 2013

The 9.5 MW solar park at Chattanooga is owned and operated by Silicon Ranch; VW has signed a 20-year power purchase agreement. Click to enlarge.

Volkswagen inaugurated its largest solar facility in the world—also the largest solar facility operated by an automaker in the US—at its plant in Chattanooga, TN, which produces the Passat model for North America. The Volkswagen Chattanooga Solar Park has a peak output of 9.5 MW. The power will be used directly in production; solar power will provide up to 12.5% of the electric power required in full-capacity operation and 100% of demand when the plant is not in production.

The new solar park is an integral part of Volkswagen’s worldwide sustainability strategy, which includes generating more power within the Group from renewable energy sources, said Volkswagen Group Officer for the Environment, Energy and New Business Areas, Wolfram Thomas.

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California Energy Commission awards more than $1.8M additional funding to further UCSD microgrid project; energy storage, EV charging and V2G services are components

January 10, 2013

The California Energy Commission (CEC) approved funding to advance further the development of its pioneering 42 MW_peak microgrid and expand electric vehicle charging at the University of California, San Diego (UCSD).

The Commission approved a $1.6-million award to increase its previously awarded funding of $1,394,298 for the university’s microgrid. The Commission also approved funding of $220,554 to expand the campus’ burgeoning charging network for plug-in electric vehicles, through the Commission’s Alternative and Renewable Fuel and Vehicle Technology Program, created by Assembly Bill 118.

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Topping-out ceremony for the Audi e-gas plant; synthetic methane production to begin in early 2013

December 13, 2012

Components of the e-gas plant. Click to enlarge.

Audi is celebrating progress on its e-gas plant under construction in Werlte, Germany with a topping-out ceremony. End products from the plant will be hydrogen and synthetic methane (Audi e-gas), to be used as fuel for vehicles such as the new Audi A3 Sportback TCNG. (Earlier post.)

The Audi e-gas plant, which can convert six megawatts of input power, will utilize renewable electricity for electrolysis, producing oxygen and hydrogen, the latter which could one day power fuel-cell vehicles. Because there is not yet a widespread hydrogen infrastructure, however, the hydrogen is reacted with CO₂ in a methanation unit to generate renewable synthetic methane, or Audi e-gas. Chemically speaking, this e-gas is nearly identical to fossil-based natural gas. As such, it can be distributed to CNG stations via the natural gas network and will power vehicles starting in 2013.

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US/China research team proposes “solar energy funnel” to harness photons for electricity; using elastic strain to capture a wider spectrum

November 26, 2012

A visualization of the broad-spectrum solar energy funnel. Image: Yan Liang. Click to enlarge.

Researchers from Peking University in China and MIT are proposing using elastic strain as a viable agent to create an optoelectronic material with a spatially varying bandgap that is tunable for use in photovoltaics, photocatalysis and photodetection. In a paper published in Nature Photonics, they propose that a photovoltaic device made from a strain-engineered MoS₂ monolayer will capture a broad range of the solar spectrum and concentrate excitons or charge carriers.

The “funnel” is a metaphor: electrons and their counterparts, holes—which are split off from atoms by the energy of photons—are driven to the center of the structure by electronic forces. However, the material actually does assume the shape of a funnel—a stretched sheet of thin material, nano-indented at its center by a microscopic needle that produces a curved, funnel-like shape.

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DOE selects Babcock & Wilcox for Small Modular Reactor program

November 21, 2012

The B&W mPower reactor integrates the nuclear core and steam generators in a single vessel. Source: B&W. Click to enlarge.

The US Department of Energy (DOE) selected a project led by Babcock & Wilcox (B&W), in partnership with the Tennessee Valley Authority and Bechtel, to design, license and help commercialize small modular reactors (SMR) in the United States. B&W will receive funding that will support accelerated development of its B&W mPower SMR technology.

This award follows a competitive funding opportunity announcement (FOA) in March 2012. (Earlier post.) In addition, DOE announced plans to issue a follow-on solicitation open to other companies and manufacturers, focused on furthering small modular reactor efficiency, operations and design.

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Researchers present new explanation for the long-range transport of PAH pollutants

November 17, 2012

When airborne particles (green) form before PAHs adhere, both the pollutants and particles dissipate quickly, as shown in the top row. But when the particles form in the presence of pollutants, which is what likely happens in nature, the longer-lasting particles enable the long-range transport of the pollutants (bottom). Credit: ACS, Zelenyuk et al. Click to enlarge.

A team led by researchers from the Pacific Northwest National Laboratory is presenting a new explanation for the long-range airborne transport (LRT) of polluting polycyclic aromatic hydrocarbons (PAHs); a paper on the work is published in the journal Environmental Science & Technology.

Pollution from fossil fuel burning and forest fires reaches all the way to the Arctic, even though it should decay long before it travels that far. The new study found that PAHs trapped inside highly viscous semisolid secondary organic aerosol (SOA) particles during particle formation are prevented from evaporation and shielded from oxidation. In contrast, surface-adsorbed PAHs rapidly evaporate leaving no trace. The results will help scientists improve atmospheric air-quality and pollution transport models.

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SwRI to demonstrate use of electric vehicles as part of emergency power microgrid under US Army SPIDERS program

November 14, 2012

Southwest Research Institute (SwRI) is a member of a team that was recently awarded a $7-million contract from the US Army Corps of Engineers to demonstrate integration of electric vehicles, generators and solar arrays to supply emergency power for Fort Carson, Colo.

The project is part of a Joint Capability Technology Demonstration (JCTD) called the Smart Power Infrastructure Demonstration for Energy Reliability and Security (SPIDERS)—a joint effort between the US Departments of Defense, Energy and Homeland Security. SPIDERS aims to create a resilient, more reliable microgrid designed to protect against extended power outages caused by natural disasters, accidents or attacks—and, ultimately, to enhance electric power surety for national security.

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IEA WEO-2012 finds major shift in global energy balance but not onto a more sustainable path; identifies potential for transformative shift in global energy efficiency

November 12, 2012

The global energy map is changing significantly, according to the 2012 edition of the Internal Energy Agency’s (IEA) World Energy Outlook (WEO-2012). The IEA said these changes will recast expectations about the role of different countries, regions and fuels in the global energy system over the coming decades. The report also finds that by 2035 global energy savings could be equivalent to nearly 20% of global demand in 2010.

The WEO finds that the extraordinary growth in oil and natural gas output in the United States will mean a sea-change in global energy flows. In the New Policies Scenario, the WEO’s central scenario, the United States becomes a net exporter of natural gas by 2020 and is almost self-sufficient in energy, in net terms, by 2035. However, given the ongoing reliance on fossil fuels, the emissions in the New Policies Scenario correspond to a long-term average global temperature increase of 3.6 °C.

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Federal Appeals Court vacates EPA Cross-State Air Pollution Rule

August 22, 2012

A three-judge panel of the US Court of Appeals for the District of Columbia held in a 2-1 opinion that the US Environmental Protection Agency (EPA) had overstepped its authority with the Cross-State Air Pollution Rule (CSAPR), and, as a result, vacated the regulation (USCA Case #11-1302). CSAPR (also called the Transport Rule) was finalized in July 2011 and replaced and strengthened the requirements of the 2005 Clean Air Interstate Rule (CAIR), which the US Court of Appeals for the DC Circuit ordered EPA to revise in 2008. (Earlier post.)

Carried long distances across the country by wind and weather, power plant emissions of sulfur dioxide (SO₂) and nitrogen oxide (NO_x) continually travel across state lines. The rule was intended to improve air quality by cutting SO₂ and NO_x emissions that contribute to pollution problems in other states. (The so-called “good neighbor” provision.)

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DOE releases new database of cost and performance estimates for electric generation, advanced vehicle, and renewable fuel technologies

July 16, 2012

TCDB plot of projected total cost of battery-electric vehicles to manufacturers. Click to enlarge.

The US Department of Energy (DOE) has released a new public database featuring cost and performance estimates for electric generation, advanced vehicle, and renewable fuel technologies. The Transparent Cost Database (TCDB) provides technology cost estimates for companies, utilities, policy makers, consumers, and academics, and can be used to benchmark company costs, model energy scenarios, and inform research and development decisions.

The database, developed by the DOE’s National Renewable Energy Laboratory (NREL) with funding from the DOE of Energy Efficiency and Renewable Energy, makes it much easier to view the range of estimates for what energy technologies, such as a utility-scale wind farm, rooftop solar installation, biofuel production plant, or an electric vehicle, might cost today or in the future.

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BP Statistical Review finds global oil share down for 12th year in a row, coal share up to highest level since 1969; renewables at 2%

June 13, 2012

World primary energy consumption grew by 2.5% in 2011, close to the historical average. Oil remains the world’s leading fuel, but its 33.1% share of consumption is the lowest on record. Coal’s market share of 30.3% was the highest since 1969. Source: BP. Click to enlarge.

Global energy consumption grew by 2.5% in 2011, broadly in line with the historical average but well below the 5.1% seen in 2010, according to the newly released BP Statistical Review of World Energy, 2012. Emerging economies accounted for all of the net growth, with OECD demand falling for the third time in the last four years, led by a sharp decline in Japan. China alone accounted for 71% of energy consumption growth.

The averages hide a mixed picture by fuel, however. Oil demand grew by less than 1%—the slowest rate amongst fossil fuels—while gas grew by 2.2%, and coal was the only fossil fuel with above average annual consumption growth at 5.4% globally, and 8.4% in the emerging economies.

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Toyota develops vehicle-to-home (V2H) power system; testing begins at the end of year

June 04, 2012

Energy management with the V2H system. Click to enlarge.

Toyota Motor Corporation (TMC) has developed a vehicle-to_home (V2H) system for the mutual sharing of power between plug-in vehicles—plug-in hybrid vehicles (PHVs) and electric vehicles (EVs)—and homes. The V2H system is to start testing, using Prius PHVs, at the end of 2012 in approximately ten households as part of the Toyota City Low-Carbon Verification Project (Toyota City Project) that began in April 2010.

The announcement follows on Nissan’s introduction of the LEAF-to-home V2H system, which can supply electricity from Nissan LEAF electric vehicles (EV) to residential homes when used with the “EV Power Station” unit—also a 6 kW charger for charging the LEAF—developed by Nichicon Corporation. (Earlier post.)

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Study projects thermoelectric power in Europe and US vulnerable to climate change due to lower summer river flows and higher river water temperatures

June 03, 2012

Projected changes in summer mean usable capacity of power plants in the US and Europe for the SRES A2 emissions scenario for the 2040s (2031–2060) relative to the control period (1971–2000). Source: van Vliet et al. Click to enlarge.

A study published in Nature Climate Change suggests that thermoelectric power plants (i.e., nuclear and fossil-fueled generating units) in Europe and the United States are vulnerable to climate change due to the combined impacts of lower summer river flows and higher river water temperatures.

In the US and Europe, at present 91% and 78% of the total electricity is produced by thermoelectric power plants, which directly depend on the availability and temperature of water resources for cooling. An international team of researchers projected a summer average decrease in capacity of power plants of 6.3—19% in Europe and 4.4—16% in the United States depending on cooling system type and climate scenario for 2031—2060. In addition, probabilities of extreme (>90%) reductions in thermoelectric power production will on average increase by a factor of three.

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Univ of Toronto study details impacts of interaction between driving patterns and electricity generation for WTW energy use and GHG emissions for PHEVs

May 23, 2012

WTW GHG emissions of vehicles across driving patterns and PHEV charging scenarios. Solid portions represent GHG emissions associated with gasoline propulsion. Patterned portions represent GHG emissions associated with electric propulsion. (Solid left bar = hydro electricity scenario.) Credit: ACS, Raykin et al. Click to enlarge.

A new study by researchers at the University of Toronto examines the impact of the interaction between driving patterns (distance and conditions) and the mode of electricity generation (e.g., coal, hydro, natural gas) on well-to-wheel (WTW) energy use and greenhouse gas (GHG) emissions of plug-in hybrid electric vehicles (PHEVs). Their paper is published is the ACS journal Environmental Science & Technology.

Driving patterns affect the WTW performance of PHEVs in two ways, they found. First, driving distance determines the proportions of electricity and gasoline consumed by the PHEV. Second, driving conditions impact the fuel efficiency of all vehicle technologies, but there are differences in the impact across technologies. Fuel efficiency, in turn, affects the magnitude of energy use and GHG emissions associated with each WTW stage.

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