Sovereign technologies [link]
2014-03-31 [www.solardaily.com/reports/Microgrid_Solar_Partners_with_Missouri_S_and_T_on_Innovative_Microgrid_Project_Centered_Around_a_Solar_Village_999.html]:
St. Louis-based Microgrid Solar is proud to be the engineer-of-record and installer of the first microgrid in the U.S. to be centered around a "Solar Village". Missouri University of Science and Technology (Missouri S and T) created the Solar Village, which consists of multiple houses built by the university's students, from 2002 to 2009, for competition in the U.S. Department of Energy's Solar Decathlon.
This competition challenges collegiate teams to design, build, and operate solar-powered houses that are cost-effective, energy-efficient, and attractive. Missouri S and T students, faculty and staff, along with members of the university's microgrid advisory board (Ameren, City Utilities of Springfield, Rolla Municipal Utilities and Electric Power Research Institute), several Missouri manufacturers (Milbank, EPRI, and Ford) and the Army Corps of Engineers, have worked together for two years to design and implement the advanced microgrid testing facility at the Rolla, Mo., campus.
The term "microgrid" is used to describe an energy "islanding" capability, whereby a campus or grouping of buildings, has the ability to operate independently from the electrical grid and other centralized power sources, creating its own smaller grid, essentially. Typically microgrids are utilized for military bases, hospitals, or other buildings campuses that involve critical power loads.
But increasingly, Microgrids are being used in a wider range of situations, and are viewed as a viable solution to improve grid stability. Most microgrids employ a combination of onsite power generation (solar, wind, gas turbines, etc), power storage, energy efficiency upgrades, and a management system.
As part of this collaboration with the project partners, Microgrid Solar was responsible for overall engineering and design, ensuring the project complies with existing electrical codes, and determining how all of the many components of this project will connect and function together efficiently.
According to Tony Arnold, Assistant Director of the Office of Sustainable Energy and Environmental Engagement at Missouri S and T, "The intent is for the microgrid to be used as a research tool and testing center for microgrid technology, battery technology and system communications. This facility will also be an exhibit for outreach and awareness of energy technology as a whole.
"Projects like these have to be scalable, replicable and flexible, so that we have the opportunity to test as many different scenarios as possible." Arnold added, "Agencies interested include major utilities, companies and the U.S. Army's Prime Power School."
Microgrids have the potential to change the way communities generate and use energy by reducing cost, increasing reliability and improving environmental performance.
"Integrating renewables and energy storage into existing electrical grids and creating reliable, stand-alone, multiple-source systems are the two most important challenges in advancing our understanding and adoption of non-fossil-fuel energy sources," said Marc Lopata, PE, the Principal Engineer on this project and President of Microgrid Solar.
"The research that Missouri S and T and the university's industry partners do with this versatile testing facility will help to pave the way for significant progress toward energy security and independence."
Monday, March 31, 2014
Tuesday, March 18, 2014
Solar thermal desalination
Sovereign technologies [link]
"California drought: Solar desalination plant shows promise"
2014-03-18 by Kevin Fagan from "San Francisco Chronicle" [http://www.sfgate.com/science/article/California-drought-Solar-desalination-plant-5326024.php]:
Quietly whirring away in a dusty field in the Central Valley is a shiny solar energy machine that may someday solve many of California's water problems.
It's called the WaterFX solar thermal desalination plant, and it has been turning salty, contaminated irrigation runoff into ultra-pure liquid for nearly a year for the Panoche Water and Drainage District. It's the only solar-driven desalination plant of its kind in the country.
Right now its efforts produce just 14,000 gallons a day. But within a year, WaterFX intends to begin expanding that one small startup plant into a sprawling collection of 36 machines that together can pump out 2 million gallons of purified water daily.
Within about five years, WaterFX company co-founder Aaron Mandell hopes to be processing 10 times that amount throughout the San Joaquin Valley. And here's the part that gets the farmers who buy his water most excited: His solar desalination plant produces water that costs about a quarter of what more conventionally desalinated water costs: $450 an acre-foot versus $2,000 an acre-foot.
An acre-foot is equivalent to an acre covered by water 1 foot deep, enough to supply two families of four for a year.
Competitive price -
That brings Mandell's water cost close to what farmers are paying, in wet years, for water from the Panoche and other valley districts - about $300 an acre-foot. And that makes it a more economically attractive option than any of the 17 conventional desalination plants planned throughout California.
If Mandell can pull it off, the tiny farming town where he is starting his enterprise could be known as ground zero for one of the most revolutionary water innovations in the state's history.
"Eventually, if this all goes where I think it can, California could wind up with so much water it's able to export it instead of having to deal with shortages," Mandell said, standing alongside the 525-foot-long solar reflector that is the heart of his machine. "What we are doing here is sustainable, scalable and affordable."
Dennis Falaschi, manager of the Panoche district, and many of the 60 farmers that constitute his customer base say the sooner WaterFX expands, the better.
Saving water -
Panoche expects to deliver about 45,000 acre-feet of water this year to its growers. That total is half of what the growers get in wetter years - but because drought and environmentally driven water mandates are not unique to 2014, the district's farmers are already ahead of the curve on water preservation techniques.
Most use drip irrigation instead of water-intensive sprinklers and are hooked up to an unusual drainage system that captures used irrigation water and directs it into fields of wheatgrass, a salt-tolerant crop sold for cattle feed. But that drainage system is little more than a creative way to get rid of irrigation water that's too salty for most uses once it leaches through farm soil.
Finding a way to make it suitable for people to drink and use on the crops they eat would be a breakthrough, Falaschi said.
"It appears this solar system will be cost-effective, and if Aaron can perform as we think he can, it can make a huge difference - be a great supplement at the very least," he said. "We're talking about basically unusable drainage water that is in everybody's interest to mine.
"This solar plant could be a very important part of where we want to be in terms of being self-sufficient in the valley."
Nothing from feds -
Panoche, like many districts in the Central Valley - the nation's most productive agricultural zone - has traditionally bought most of its water from the federally run Central Valley Project. But in this drought year, farmers are likely to get zero allocation from the project.
If that happens, Panoche will have to draw from leftover supply, the expensive spot water market and wells. All of that is pricier than usual, with the spot market alone charging as much as $3,500 an acre-foot.
"This situation right now is a killer, and anything that adds to a potential water supply is good," said Mike Stearns, a fourth-generation farmer in the Panoche district who is fallowing most of his tomato, onion and other fields this year because of the drought. He's concentrating on his wine grapes, which are thirsty but promise a good profit even in a drought year.
"And keep in mind that this water shortage doesn't just affect farmers," Stearns said. "Think about the jobs that are lost when we have to fallow our fields. Or the taxes that the government won't get because we aren't growing and selling. It's bad. We need to do everything we can about this."
Simple process -
The way the solar plant works is simple, which is why the water it produces is cheap.
Water that dribbles down from nearby hills, and through the soil in the Central Valley after being used for irrigation, collects so much salt, selenium, boron and other minerals that it's not fit for human consumption. The solar plant captures the foothill runoff and sucks in used irrigation water from a French drain-style system 6 to 8 feet under the crops, and sends that tainted water through a series of pipes and tanks that heat it.
The heat comes from the plant's huge, parabolic-shaped solar reflector, which focuses the sun on a long tube containing mineral oil. That heated tube in turn creates steam, which condenses the brackish water into usable liquid, separating out the minerals.
The water then goes back out for irrigation. Mandell says that because his condensation method distills the minerals more efficiently than other desalination methods, he is installing a system that will process them for use. Selenium and boron can be vitamin supplements, for example, and gypsum can be used for drywall.
More conventional desalination plants - such as a $1 billion operation being built near San Diego - use a reverse osmosis process, in which brackish water is forced through screens to filter out the contaminants. That requires a lot of energy, which is why it is more expensive.
Raising money -
WaterFX's pilot plant cost $1 million in state grants to build last summer. The expansion of the 36-plant complex would cost as much as $30 million, which Mandell is working on raising.
"It does seem like this system is in a great location," said Daniel Choi, an analyst with Lux Research, which researches emerging technology. "It's where it should be - an area with a lot of sunlight, where reverse osmosis doesn't make the most sense large-scale. It does seem like it's viable.
"I wouldn't be surprised if WaterFX expanded to other markets."
Mandell's expanded solar plant would be able to deliver 2,200 acre-feet of water next year - and if that performs as hoped, within a few years his ambition is to scale it up to 20,000 acre-feet. That would meet nearly half of the current demand from Panoche district farmers.
"Eventually we could process not just drainage water, but industrial and residential wastewater as well as groundwater that now is too salty to use," Mandell said. Such desalination already happens on a large scale in other parts of the world, particularly the Middle East, he pointed out.
Sinking land -
Drawing groundwater, however - even groundwater that's now too salty to drink - could prove problematic in the Central Valley. Years of tapping usable groundwater have so depleted aquifers that in some places the land has sunk 30 feet since the 1920s.
There are trillions of gallons of brackish groundwater available in California, said Claudia Faunt, a U.S. Geological Survey hydrologist, and much of that has not been tapped because it is closer to the surface than the purer liquid deeper down. However, "to say there wouldn't be subsidence (if it were tapped) is an unknown," she said.
For now, Mandell said, he and his partners are focusing on drainage water - and that alone is a major issue.
"Look, there are 200 million tons of salt on the land in the Central Valley, and billions of gallons of drainage water, and cleaning up that drainage water is a huge issue," said WaterFX's chief consultant, Bruce Marlow. "I'd say if we can control the saline in the valley, in 10 years we might not have to rely on the federal water system here at all."
"California drought: Solar desalination plant shows promise"
2014-03-18 by Kevin Fagan from "San Francisco Chronicle" [http://www.sfgate.com/science/article/California-drought-Solar-desalination-plant-5326024.php]:
Quietly whirring away in a dusty field in the Central Valley is a shiny solar energy machine that may someday solve many of California's water problems.
It's called the WaterFX solar thermal desalination plant, and it has been turning salty, contaminated irrigation runoff into ultra-pure liquid for nearly a year for the Panoche Water and Drainage District. It's the only solar-driven desalination plant of its kind in the country.
Right now its efforts produce just 14,000 gallons a day. But within a year, WaterFX intends to begin expanding that one small startup plant into a sprawling collection of 36 machines that together can pump out 2 million gallons of purified water daily.
Within about five years, WaterFX company co-founder Aaron Mandell hopes to be processing 10 times that amount throughout the San Joaquin Valley. And here's the part that gets the farmers who buy his water most excited: His solar desalination plant produces water that costs about a quarter of what more conventionally desalinated water costs: $450 an acre-foot versus $2,000 an acre-foot.
An acre-foot is equivalent to an acre covered by water 1 foot deep, enough to supply two families of four for a year.
Competitive price -
That brings Mandell's water cost close to what farmers are paying, in wet years, for water from the Panoche and other valley districts - about $300 an acre-foot. And that makes it a more economically attractive option than any of the 17 conventional desalination plants planned throughout California.
If Mandell can pull it off, the tiny farming town where he is starting his enterprise could be known as ground zero for one of the most revolutionary water innovations in the state's history.
"Eventually, if this all goes where I think it can, California could wind up with so much water it's able to export it instead of having to deal with shortages," Mandell said, standing alongside the 525-foot-long solar reflector that is the heart of his machine. "What we are doing here is sustainable, scalable and affordable."
Dennis Falaschi, manager of the Panoche district, and many of the 60 farmers that constitute his customer base say the sooner WaterFX expands, the better.
Saving water -
Panoche expects to deliver about 45,000 acre-feet of water this year to its growers. That total is half of what the growers get in wetter years - but because drought and environmentally driven water mandates are not unique to 2014, the district's farmers are already ahead of the curve on water preservation techniques.
Most use drip irrigation instead of water-intensive sprinklers and are hooked up to an unusual drainage system that captures used irrigation water and directs it into fields of wheatgrass, a salt-tolerant crop sold for cattle feed. But that drainage system is little more than a creative way to get rid of irrigation water that's too salty for most uses once it leaches through farm soil.
Finding a way to make it suitable for people to drink and use on the crops they eat would be a breakthrough, Falaschi said.
"It appears this solar system will be cost-effective, and if Aaron can perform as we think he can, it can make a huge difference - be a great supplement at the very least," he said. "We're talking about basically unusable drainage water that is in everybody's interest to mine.
"This solar plant could be a very important part of where we want to be in terms of being self-sufficient in the valley."
Nothing from feds -
Panoche, like many districts in the Central Valley - the nation's most productive agricultural zone - has traditionally bought most of its water from the federally run Central Valley Project. But in this drought year, farmers are likely to get zero allocation from the project.
If that happens, Panoche will have to draw from leftover supply, the expensive spot water market and wells. All of that is pricier than usual, with the spot market alone charging as much as $3,500 an acre-foot.
"This situation right now is a killer, and anything that adds to a potential water supply is good," said Mike Stearns, a fourth-generation farmer in the Panoche district who is fallowing most of his tomato, onion and other fields this year because of the drought. He's concentrating on his wine grapes, which are thirsty but promise a good profit even in a drought year.
"And keep in mind that this water shortage doesn't just affect farmers," Stearns said. "Think about the jobs that are lost when we have to fallow our fields. Or the taxes that the government won't get because we aren't growing and selling. It's bad. We need to do everything we can about this."
Simple process -
The way the solar plant works is simple, which is why the water it produces is cheap.
Water that dribbles down from nearby hills, and through the soil in the Central Valley after being used for irrigation, collects so much salt, selenium, boron and other minerals that it's not fit for human consumption. The solar plant captures the foothill runoff and sucks in used irrigation water from a French drain-style system 6 to 8 feet under the crops, and sends that tainted water through a series of pipes and tanks that heat it.
The heat comes from the plant's huge, parabolic-shaped solar reflector, which focuses the sun on a long tube containing mineral oil. That heated tube in turn creates steam, which condenses the brackish water into usable liquid, separating out the minerals.
The water then goes back out for irrigation. Mandell says that because his condensation method distills the minerals more efficiently than other desalination methods, he is installing a system that will process them for use. Selenium and boron can be vitamin supplements, for example, and gypsum can be used for drywall.
More conventional desalination plants - such as a $1 billion operation being built near San Diego - use a reverse osmosis process, in which brackish water is forced through screens to filter out the contaminants. That requires a lot of energy, which is why it is more expensive.
Raising money -
WaterFX's pilot plant cost $1 million in state grants to build last summer. The expansion of the 36-plant complex would cost as much as $30 million, which Mandell is working on raising.
"It does seem like this system is in a great location," said Daniel Choi, an analyst with Lux Research, which researches emerging technology. "It's where it should be - an area with a lot of sunlight, where reverse osmosis doesn't make the most sense large-scale. It does seem like it's viable.
"I wouldn't be surprised if WaterFX expanded to other markets."
Mandell's expanded solar plant would be able to deliver 2,200 acre-feet of water next year - and if that performs as hoped, within a few years his ambition is to scale it up to 20,000 acre-feet. That would meet nearly half of the current demand from Panoche district farmers.
"Eventually we could process not just drainage water, but industrial and residential wastewater as well as groundwater that now is too salty to use," Mandell said. Such desalination already happens on a large scale in other parts of the world, particularly the Middle East, he pointed out.
Sinking land -
Drawing groundwater, however - even groundwater that's now too salty to drink - could prove problematic in the Central Valley. Years of tapping usable groundwater have so depleted aquifers that in some places the land has sunk 30 feet since the 1920s.
There are trillions of gallons of brackish groundwater available in California, said Claudia Faunt, a U.S. Geological Survey hydrologist, and much of that has not been tapped because it is closer to the surface than the purer liquid deeper down. However, "to say there wouldn't be subsidence (if it were tapped) is an unknown," she said.
For now, Mandell said, he and his partners are focusing on drainage water - and that alone is a major issue.
"Look, there are 200 million tons of salt on the land in the Central Valley, and billions of gallons of drainage water, and cleaning up that drainage water is a huge issue," said WaterFX's chief consultant, Bruce Marlow. "I'd say if we can control the saline in the valley, in 10 years we might not have to rely on the federal water system here at all."
Residential Solar Power Units
Sovereign technologies [link]. Solar Power is an enhancement of sovereignty, however, this technology is created through the use of resources extracted from foreign sources, and, as such, does not constitute as a sovereign technology. Solar Power does enhance community sovereignty by allowing for an alternative to monopolized high-yield energy production.
"SolarCity accuses utilities of slowing home-battery project"
2014-03-18 by David R. Baker from "San Francisco Chronicle" [http://www.sfgate.com/business/article/SolarCity-accuses-utilities-of-slowing-5325791.php]:
SolarCity wants to connect rooftop solar panels to batteries that would store power for use at night. (Photo: Ed Andrieski, Associated Press)
For more than two years, SolarCity Corp. has been trying to launch an experiment that could change the way we power our homes.
The San Mateo company has installed battery packs in more than 100 houses throughout California, each pack linked to rooftop solar panels. The lithium-ion batteries, made by Tesla Motors, store electricity from the panels during the day for use at night.
That combination - solar on the roof, batteries in the basement - could one day revolutionize the energy industry, undercutting traditional utility companies.
So the utilities, SolarCity says, are fighting back.
California's big electricity providers are dragging their feet on connecting the batteries to the grid and charging steep fees - nearly $3,700 per customer, in some cases - to do so, according to SolarCity.
"We all know this is a game-changing product," said SolarCity CEO Lyndon Rive, speaking at a recent public forum in which he complained about the delays. "Those in the game don't want to change the game. They really like the existing game."
SolarCity, which made its name leasing solar arrays to homeowners and businesses, quietly started offering batteries to its residential customers in November 2011. More than 500 have signed up so far. Of those, just over 100 have received their battery packs.
But most of them still can't use the batteries.
Only 12 connections -
Since the pilot program started, utilities have only connected 12 of those battery systems to the grid, according to SolarCity. Pacific Gas and Electric Co. has hooked up 11 customers, while San Diego Gas and Electric Co. has connected one. Southern California Edison has not connected any, even though SolarCity has submitted 10 applications to the utility.
Lee Middleman of Portola Valley has been waiting almost four months.
Longtime SolarCity customers, he and his wife, Donnie, jumped at the chance to add a storage pack when the company started the program. They belong to a community emergency response team and understand the value of being able to generate and store their own electricity if the grid goes down.
"It's a little remote, here, and when the power goes out, it'd be nice to have a backup system," said Middleman, a ceramic artist. "If there's an earthquake, we know Portola Valley is going to be one of the last places PG&E will service, because they're going to start with the more densely populated place first."
But for now, the battery pack, complete with Tesla logo, sits unused. (Tesla CEO Elon Musk chairs SolarCity's board of directors, and Rive is his cousin.)
"It seems like they're throwing every possible roadblock in front of this thing to slow it down," Middleman said.
PG&E charges $800 for each application, plus a $600 fee whenever the utility decides that the solar-and-battery system needs a new electric meter. Southern California Edison charges the same application fee, plus $2,898 to install and connect the meter, according to documents SolarCity provided to The Chronicle.
SolarCity contends that the application fees are illegal, saying they conflict with a state law that governs how utility companies deal with home solar arrays.
Won't rush -
PG&E insists it is not trying to block or delay SolarCity's energy storage program. But Steve Malnight, PG&E's vice president of customer energy solutions, said the company won't rush its process for inspecting the new systems and connecting them to the grid. The current wait time, he said, is eight to 10 weeks.
"We're not satisfied with that time, in the long run, but this is a new technology," Malnight said. "Our focus is on ensuring safety and reliability for the customers. I think that's appropriate."
A Southern California Edison spokesman was not able to comment for this story by press time.
"SolarCity accuses utilities of slowing home-battery project"
2014-03-18 by David R. Baker from "San Francisco Chronicle" [http://www.sfgate.com/business/article/SolarCity-accuses-utilities-of-slowing-5325791.php]:
SolarCity wants to connect rooftop solar panels to batteries that would store power for use at night. (Photo: Ed Andrieski, Associated Press)
For more than two years, SolarCity Corp. has been trying to launch an experiment that could change the way we power our homes.
The San Mateo company has installed battery packs in more than 100 houses throughout California, each pack linked to rooftop solar panels. The lithium-ion batteries, made by Tesla Motors, store electricity from the panels during the day for use at night.
That combination - solar on the roof, batteries in the basement - could one day revolutionize the energy industry, undercutting traditional utility companies.
So the utilities, SolarCity says, are fighting back.
California's big electricity providers are dragging their feet on connecting the batteries to the grid and charging steep fees - nearly $3,700 per customer, in some cases - to do so, according to SolarCity.
"We all know this is a game-changing product," said SolarCity CEO Lyndon Rive, speaking at a recent public forum in which he complained about the delays. "Those in the game don't want to change the game. They really like the existing game."
SolarCity, which made its name leasing solar arrays to homeowners and businesses, quietly started offering batteries to its residential customers in November 2011. More than 500 have signed up so far. Of those, just over 100 have received their battery packs.
But most of them still can't use the batteries.
Only 12 connections -
Since the pilot program started, utilities have only connected 12 of those battery systems to the grid, according to SolarCity. Pacific Gas and Electric Co. has hooked up 11 customers, while San Diego Gas and Electric Co. has connected one. Southern California Edison has not connected any, even though SolarCity has submitted 10 applications to the utility.
Lee Middleman of Portola Valley has been waiting almost four months.
Longtime SolarCity customers, he and his wife, Donnie, jumped at the chance to add a storage pack when the company started the program. They belong to a community emergency response team and understand the value of being able to generate and store their own electricity if the grid goes down.
"It's a little remote, here, and when the power goes out, it'd be nice to have a backup system," said Middleman, a ceramic artist. "If there's an earthquake, we know Portola Valley is going to be one of the last places PG&E will service, because they're going to start with the more densely populated place first."
But for now, the battery pack, complete with Tesla logo, sits unused. (Tesla CEO Elon Musk chairs SolarCity's board of directors, and Rive is his cousin.)
"It seems like they're throwing every possible roadblock in front of this thing to slow it down," Middleman said.
PG&E charges $800 for each application, plus a $600 fee whenever the utility decides that the solar-and-battery system needs a new electric meter. Southern California Edison charges the same application fee, plus $2,898 to install and connect the meter, according to documents SolarCity provided to The Chronicle.
SolarCity contends that the application fees are illegal, saying they conflict with a state law that governs how utility companies deal with home solar arrays.
Won't rush -
PG&E insists it is not trying to block or delay SolarCity's energy storage program. But Steve Malnight, PG&E's vice president of customer energy solutions, said the company won't rush its process for inspecting the new systems and connecting them to the grid. The current wait time, he said, is eight to 10 weeks.
"We're not satisfied with that time, in the long run, but this is a new technology," Malnight said. "Our focus is on ensuring safety and reliability for the customers. I think that's appropriate."
A Southern California Edison spokesman was not able to comment for this story by press time.
Friday, March 7, 2014
Hydrogen fuel created which can retain 90% of energy collected from Solar Power, created by the Joint Center for Artificial Photosynthesis (JCAP)
Sovereign technologies [link]
"Promising News for Solar Fuels from Berkeley Lab Researchers at JCAP"
2014-03-07 by Lynn Yarris from "Lawrence Berkeley National Laboratory"
[http://newscenter.lbl.gov/science-shorts/2014/03/07/promising-news-for-solar-fuels/]:
For more about Joint Center for Artificial Photosynthesis go here [http://solarfuelshub.org/].
There’s promising news from the front on efforts to produce fuels through artificial photosynthesis. A new study by Berkeley Lab researchers at the Joint Center for Artificial Photosynthesis (JCAP) shows that nearly 90-percent of the electrons generated by a hybrid material designed to store solar energy in hydrogen are being stored in the target hydrogen molecules.
Gary Moore, a chemist and principal investigator with Berkeley Lab’s Physical Biosciences Division, led an efficiency analysis study of a unique photocathode material he and his research group have developed for catalyzing the production of hydrogen fuel from sunlight. This material, a hybrid formed from interfacing the semiconductor gallium phosphide with a molecular hydrogen-producing cobaloxime catalyst, has the potential to address one of the major challenges in the use of artificial photosynthesis to make renewable solar fuels.
“Ultimately the renewable energy problem is really a storage problem,” Moore says. “Given the intermittent availability of sunlight, we need a way of using the sun all night long. Storing solar energy in the chemical bonds of a fuel also provides the large power densities that are essential to modern transport systems. We’ve shown that our approach of coupling the absorption of visible light with the production of hydrogen in a single material puts photoexcited electrons where we need them to be, stored in chemical bonds.”
Moore is the corresponding author of a paper describing this research in the journal Physical Chemistry Chemical Physics titled “Energetics and efficiency analysis of a cobaloxime-modified semiconductor under simulated air mass 1.5 illumination.” Co-authors are Alexandra Krawicz and Diana Cedeno.
Bionic leaves that produce energy-dense fuels from nothing more than sunlight, water and atmosphere-warming carbon dioxide, with no byproducts other than oxygen, represent an ideal sustainable energy alternative to fossil fuels. However, realizing this artificial photosynthesis ideal will require a number of technological breakthroughs including high performance photocathodes that can catalyze fuel production from sunlight alone.
Last year, Moore and his research group at JCAP took an important step towards the photocathode goal with their gallium phosphide/cobaloxime hybrid. Gallium phosphide is an absorber of visible light, which enables it to produce significantly higher photocurrents than semiconductors that only absorb ultraviolet light. The cobaloxime catalyst is also Earth-abundant, meaning it is a relatively inexpensive replacement for the highly expensive precious metal catalysts, such as platinum, currently used in many solar-fuel generator prototypes.
“The novelty of our approach is the use of molecular catalytic components interfaced with visible-light absorbing semiconductors,” Moore says. “This creates opportunities to use discrete three-dimensional environments for directly photoactivating the multi-electron and multi-proton chemistry associated with the production of hydrogen and other fuels.”
The efficiency analysis performed by Moore and his colleagues also confirmed that the light-absorber component of their photocathode is a major bottleneck to obtaining higher current densities. Their results showed that of the total number of solar photons striking the hybrid-semiconductor surface, measured over the entire wavelength range of the solar spectrum (from 200 to 4,000 nanometers) only 1.5-percent gave rise to a photocurrent.
“This tells us that the use of light absorbers with improved spectral coverage of the sun is a good start to achieving further performance gains, but it is likely we will also have to develop faster and more efficient catalysts as well as new attachment chemistries. Our modular assembly method provides a viable strategy to testing promising combinations of new materials,” Moore says.
“Efficiency is not the only consideration that should go into evaluating materials for applications in solar-fuel generator technologies. Along with the durability and feasible scalability of components, the selectivity of photoactivating a targeted reaction is also critical. This is where molecular approaches offer significant opportunities, especially in catalyzing complex chemical transformations such as the reduction of carbon dioxide.”
JCAP, which has a northern branch in Berkeley and a southern branch on the campus of the California Institute of Technology (Caltech), was established in 2010 by the U.S. Department of Energy (DOE) as an Energy Innovation Hub. Operated as a partnership between Caltech and Berkeley Lab, JCAP is the largest research program in the United States dedicated to developing an artificial solar-fuel technology. It is funded through the DOE Office of Science.
---
From left, Diana Cedeno, Gary Moore and Alexandra Krawicz of the Joint Center for Artificial Photosynthesis conducted an efficiency analysis study of a unique photocathode material designed to store solar energy in hydrogen molecules. (Photo by Roy Kaltschmidt)
"Promising News for Solar Fuels from Berkeley Lab Researchers at JCAP"
2014-03-07 by Lynn Yarris from "Lawrence Berkeley National Laboratory"
[http://newscenter.lbl.gov/science-shorts/2014/03/07/promising-news-for-solar-fuels/]:
For more about Joint Center for Artificial Photosynthesis go here [http://solarfuelshub.org/].
There’s promising news from the front on efforts to produce fuels through artificial photosynthesis. A new study by Berkeley Lab researchers at the Joint Center for Artificial Photosynthesis (JCAP) shows that nearly 90-percent of the electrons generated by a hybrid material designed to store solar energy in hydrogen are being stored in the target hydrogen molecules.
Gary Moore, a chemist and principal investigator with Berkeley Lab’s Physical Biosciences Division, led an efficiency analysis study of a unique photocathode material he and his research group have developed for catalyzing the production of hydrogen fuel from sunlight. This material, a hybrid formed from interfacing the semiconductor gallium phosphide with a molecular hydrogen-producing cobaloxime catalyst, has the potential to address one of the major challenges in the use of artificial photosynthesis to make renewable solar fuels.
“Ultimately the renewable energy problem is really a storage problem,” Moore says. “Given the intermittent availability of sunlight, we need a way of using the sun all night long. Storing solar energy in the chemical bonds of a fuel also provides the large power densities that are essential to modern transport systems. We’ve shown that our approach of coupling the absorption of visible light with the production of hydrogen in a single material puts photoexcited electrons where we need them to be, stored in chemical bonds.”
Moore is the corresponding author of a paper describing this research in the journal Physical Chemistry Chemical Physics titled “Energetics and efficiency analysis of a cobaloxime-modified semiconductor under simulated air mass 1.5 illumination.” Co-authors are Alexandra Krawicz and Diana Cedeno.
Bionic leaves that produce energy-dense fuels from nothing more than sunlight, water and atmosphere-warming carbon dioxide, with no byproducts other than oxygen, represent an ideal sustainable energy alternative to fossil fuels. However, realizing this artificial photosynthesis ideal will require a number of technological breakthroughs including high performance photocathodes that can catalyze fuel production from sunlight alone.
Last year, Moore and his research group at JCAP took an important step towards the photocathode goal with their gallium phosphide/cobaloxime hybrid. Gallium phosphide is an absorber of visible light, which enables it to produce significantly higher photocurrents than semiconductors that only absorb ultraviolet light. The cobaloxime catalyst is also Earth-abundant, meaning it is a relatively inexpensive replacement for the highly expensive precious metal catalysts, such as platinum, currently used in many solar-fuel generator prototypes.
“The novelty of our approach is the use of molecular catalytic components interfaced with visible-light absorbing semiconductors,” Moore says. “This creates opportunities to use discrete three-dimensional environments for directly photoactivating the multi-electron and multi-proton chemistry associated with the production of hydrogen and other fuels.”
The efficiency analysis performed by Moore and his colleagues also confirmed that the light-absorber component of their photocathode is a major bottleneck to obtaining higher current densities. Their results showed that of the total number of solar photons striking the hybrid-semiconductor surface, measured over the entire wavelength range of the solar spectrum (from 200 to 4,000 nanometers) only 1.5-percent gave rise to a photocurrent.
“This tells us that the use of light absorbers with improved spectral coverage of the sun is a good start to achieving further performance gains, but it is likely we will also have to develop faster and more efficient catalysts as well as new attachment chemistries. Our modular assembly method provides a viable strategy to testing promising combinations of new materials,” Moore says.
“Efficiency is not the only consideration that should go into evaluating materials for applications in solar-fuel generator technologies. Along with the durability and feasible scalability of components, the selectivity of photoactivating a targeted reaction is also critical. This is where molecular approaches offer significant opportunities, especially in catalyzing complex chemical transformations such as the reduction of carbon dioxide.”
JCAP, which has a northern branch in Berkeley and a southern branch on the campus of the California Institute of Technology (Caltech), was established in 2010 by the U.S. Department of Energy (DOE) as an Energy Innovation Hub. Operated as a partnership between Caltech and Berkeley Lab, JCAP is the largest research program in the United States dedicated to developing an artificial solar-fuel technology. It is funded through the DOE Office of Science.
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From left, Diana Cedeno, Gary Moore and Alexandra Krawicz of the Joint Center for Artificial Photosynthesis conducted an efficiency analysis study of a unique photocathode material designed to store solar energy in hydrogen molecules. (Photo by Roy Kaltschmidt)
Thursday, March 6, 2014
"Solano Community College District Celebrates 2.8MW of SunPower Solar Power Systems"
Sovereign technologies [link]
2014-03-06 from "Solar Daily" newswire [http://www.solardaily.com/reports/Solano_Community_College_District_Celebrates_2_point_8MW_of_SunPower_Solar_Power_Systems_999.html]:
Fairfield CA -
Solano Community College District (SCCD), SunPower and Kitchell have dedicated 2.8 megawatts of solar power systems installed at three district locations. According to SCCD, the systems are expected to generate enough electricity to meet as much as 50 percent or more of annual electricity demand at the three sites.
"Solar power is a reliable, affordable means to reduce our operational costs as well as our dependence on fossil fuels," said SCCD Vice President of Finance and Administration Yulian Ligioso.
"With SunPower as our solar technology provider, we expect the systems will generate significant savings over the next 25 years for the benefit of the district, our students and our communities."
SunPower designed and constructed the systems, which are installed on solar parking canopies at the district's Fairfield campus, and at district centers in Vacaville and Vallejo. The systems use high efficiency SunPower solar panels, the most efficient panels on the market today. Kitchell performed program management services and provided construction oversight for the district at all three locations.
"Installing these high efficiency systems on solar shade structures in parking lots allows the district to maximize the clean, renewable energy generated while taking advantage of underutilized space and providing needed shade," said Howard Wenger, SunPower president, regions.
"With on-campus SunPower systems that deliver guaranteed performance, Solano Community College District can realize long-term savings that can be used to enhance academic programs."
According to industry estimates provided by the U.S. Environmental Protection Agency, the 2.8 megawatts of SunPower systems are expected to offset the production of roughly 2,200 tons of greenhouse gas emissions, which is equivalent to removing approximately 10,850 passenger vehicles from California's highways over the next 25 years.
SunPower has installed approximately 20 megawatts of solar power systems at 12 community college districts in California. The systems are generating enough clean, renewable solar electricity to power more than 4,100 California homes each year, according to calculations provided by the Solar Energy Industries Association. At current utility rates, it's estimated the districts are avoiding approximately $5.4 million in annual electricity costs.
2014-03-06 from "Solar Daily" newswire [http://www.solardaily.com/reports/Solano_Community_College_District_Celebrates_2_point_8MW_of_SunPower_Solar_Power_Systems_999.html]:
Fairfield CA -
Solano Community College District (SCCD), SunPower and Kitchell have dedicated 2.8 megawatts of solar power systems installed at three district locations. According to SCCD, the systems are expected to generate enough electricity to meet as much as 50 percent or more of annual electricity demand at the three sites.
"Solar power is a reliable, affordable means to reduce our operational costs as well as our dependence on fossil fuels," said SCCD Vice President of Finance and Administration Yulian Ligioso.
"With SunPower as our solar technology provider, we expect the systems will generate significant savings over the next 25 years for the benefit of the district, our students and our communities."
SunPower designed and constructed the systems, which are installed on solar parking canopies at the district's Fairfield campus, and at district centers in Vacaville and Vallejo. The systems use high efficiency SunPower solar panels, the most efficient panels on the market today. Kitchell performed program management services and provided construction oversight for the district at all three locations.
"Installing these high efficiency systems on solar shade structures in parking lots allows the district to maximize the clean, renewable energy generated while taking advantage of underutilized space and providing needed shade," said Howard Wenger, SunPower president, regions.
"With on-campus SunPower systems that deliver guaranteed performance, Solano Community College District can realize long-term savings that can be used to enhance academic programs."
According to industry estimates provided by the U.S. Environmental Protection Agency, the 2.8 megawatts of SunPower systems are expected to offset the production of roughly 2,200 tons of greenhouse gas emissions, which is equivalent to removing approximately 10,850 passenger vehicles from California's highways over the next 25 years.
SunPower has installed approximately 20 megawatts of solar power systems at 12 community college districts in California. The systems are generating enough clean, renewable solar electricity to power more than 4,100 California homes each year, according to calculations provided by the Solar Energy Industries Association. At current utility rates, it's estimated the districts are avoiding approximately $5.4 million in annual electricity costs.
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