Technology Review of December 18, 2009 had an article entitled, Hot Electrons Could Double Solar Power. It's worth a little review of how solar photovoltaic cells work. A PV is essentially two layers of semiconductor material, one of which has an excess of electrons and the other a shortage of electrons. When a photon from the sun hits an electron, it dislodges it, sends it through a curuit, to the other side, creating electricity.
The article discusses how certain of these electrons respond to different wavelengths of sunlight. Some PV cells are adapted to one wavelength or another. In the blue light wavelength of the sun, the electrons have high energy, but it dissipates as heat before it can escape the cell and produce electricity. Researchers are finding ways to make the PV cell sufficiently thin and configured in such a way, as to take advantage of these "hot electrons" and produce much more electricity from a given surface area than the current state of the art of photovoltaics.
In my book, How to Tell a Btu from a BLT, I discuss in my chapter on solar energy the heat transfer mechanism by which the sun's heat is transmitted through the vacuum of space and the fact that PV cells have efficiencies ranging from 8% to 35%. The Technology Review article reports the promise of PVs with an efficiency of 67%. This is an enormous breakthrough in solar technology. It has an enormously positive impact on land use for central station generation using photovoltaics. Moreover, it brings distributed generation using photovoltaics one step further toward reality. One can imagine a the day when a significant portion of household power requirements come from a PV array on one's roof during the day (especially in the Southwest) and we rely on the grid at night. This would relieve a huge burden of building new generation and transmission infrastructure by the nation's electric utilities. But most amazingly, 67% efficiency is a twice the efficiency of the average coal or nuclear steam generating plant that exists today. Now that's progress!
Wednesday, December 23, 2009
Sunday, September 27, 2009
Sunday New York Times - Solar Power That Blends In
Sunday's (9/27/09) New York Times (Sunday Business) - Solar Power, Without All those Panels is a very interesting advance in the use of photovoltaic cells and one I would like to see more use of. It seems to me that the use of solar power as a distributed generation alternative, rather than a central station alternative, is best use and best practices.
Home builders are including "building integrated photovoltaics" in roof tiles that will generate power directly into the home. The article provides an example of one product, installed in a California home, that will generate 2,400 kilowatt-hours per year for about 300 square feet of roofing tiles that contain photovoltaic cells. If you use about 1000 kilowatt-hours per month, this will reduce your consumption of central station power by 20%. That is a huge reduction in consumption and, if universally applied, would reduce the need for new power plants and transmission lines in the U.S. very significantly. It might also shift some of our electricity consumption from central station power plants from periods of peak consumption into off-peak periods because the solar roofs would be generating power when we need it most: at the peak time of day when the sun is shining, hottest temperatures and peak air conditioning consumption.
This fits very well with the concept I propose in my book (How to Tell a BTU from a BLT): Conservation Without Deprivation!
Home builders are including "building integrated photovoltaics" in roof tiles that will generate power directly into the home. The article provides an example of one product, installed in a California home, that will generate 2,400 kilowatt-hours per year for about 300 square feet of roofing tiles that contain photovoltaic cells. If you use about 1000 kilowatt-hours per month, this will reduce your consumption of central station power by 20%. That is a huge reduction in consumption and, if universally applied, would reduce the need for new power plants and transmission lines in the U.S. very significantly. It might also shift some of our electricity consumption from central station power plants from periods of peak consumption into off-peak periods because the solar roofs would be generating power when we need it most: at the peak time of day when the sun is shining, hottest temperatures and peak air conditioning consumption.
This fits very well with the concept I propose in my book (How to Tell a BTU from a BLT): Conservation Without Deprivation!
Sunday, September 13, 2009
The Modular, Scalable Nuclear Reactor
Anyone who has been involved in the engineering design and construction of a new nuclear power plant will admit the process is long, risky (financially) and with too much government red tape and delays. They will also tell you that as a result, you only get one shot at building a nuke--so build it big. The latest crop of nuclear power plant designs are 1,100 MWe (Westinghouse/Toshiba) and an astounding 1,700 MWe (Mitshubishi Heavy Industries).
Along comes Babcock & Wilcox (a company well experienced in electric power and with a big nuclear design of its own when the first 104 U.S. Nukes were developed) with mPower, a modular, scalable nuclear plant that comes in sizes ranging from 125 MWe to 750MWe. These designs are safer than the existing fleet and the newer designs because the configuration is such that it eliminates the worst design basis accident that is postulated: the LOSS OF COOLANT ACCIDENT or LOCA. The existing fleet and the newer nuclear offerings have to be designed to withstand a break in the main piping that cools the reactor core--LOCA. Much of the regulatory angst and engineering challenges surround this hypothetical accident.
B&W's design is different. It is totally self contained and, therefore, does not include the system (Reactor Coolant Loop) that requires engineers to worry about its breaking. The other advantages are reduced regulatory requirements, only a three year construction cycle and a five year refueling cycle, meaning the utility only has to replace the nuclear fuel every five years, instead of every 18 months prevalent today.
The other obvious advantages are that smaller utilities can take advantage of nuclear power because it can be built in smaller, more affordable increments in much less time than the big units. In addition, it can be built in smaller pieces providing system flexibility. A small utility cannot afford to lose 1000 MWe of power when a plant has a forced outage if it only has a 4000 MWe system. So it can't build plants that are so big. However, if it can build 125 MWe or 25o MWe, the system can maintain its flexibility and reliabilty if a unit is forced out of service.
This is the type of nuclear plant innovation that will allow the U.S. to achieve the long process of weaning itself off of polluting fossil fuels.
Along comes Babcock & Wilcox (a company well experienced in electric power and with a big nuclear design of its own when the first 104 U.S. Nukes were developed) with mPower, a modular, scalable nuclear plant that comes in sizes ranging from 125 MWe to 750MWe. These designs are safer than the existing fleet and the newer designs because the configuration is such that it eliminates the worst design basis accident that is postulated: the LOSS OF COOLANT ACCIDENT or LOCA. The existing fleet and the newer nuclear offerings have to be designed to withstand a break in the main piping that cools the reactor core--LOCA. Much of the regulatory angst and engineering challenges surround this hypothetical accident.
B&W's design is different. It is totally self contained and, therefore, does not include the system (Reactor Coolant Loop) that requires engineers to worry about its breaking. The other advantages are reduced regulatory requirements, only a three year construction cycle and a five year refueling cycle, meaning the utility only has to replace the nuclear fuel every five years, instead of every 18 months prevalent today.
The other obvious advantages are that smaller utilities can take advantage of nuclear power because it can be built in smaller, more affordable increments in much less time than the big units. In addition, it can be built in smaller pieces providing system flexibility. A small utility cannot afford to lose 1000 MWe of power when a plant has a forced outage if it only has a 4000 MWe system. So it can't build plants that are so big. However, if it can build 125 MWe or 25o MWe, the system can maintain its flexibility and reliabilty if a unit is forced out of service.
This is the type of nuclear plant innovation that will allow the U.S. to achieve the long process of weaning itself off of polluting fossil fuels.
Saturday, August 8, 2009
Cafe Etiquette
Yesterday's WSJ Article ("No More Perks: Coffee Shops Pull the Plug on Laptop Users" ) discusses shop owners' frustration with loitering laptop users who take advantage of free electricity and WiFi while buying nothing and displacing paying customers.
It points up how oblivious we all are to our use of energy both direct and indirect. When we use the internet we either have a desktop plugged in, a laptop we have had to charge up or some other portable device that also had to be charged. But we speak with forked tongue: We speak conservation and renewables out of one side of our mouths and banter about this great, energy consuming technology out of the other side.
Remember, the internet isn't in the airwaves because angels deliver it on splendid wings. There are servers, mountains of servers, all over the world that provide us with the internet. And they require power. Lots of it. Moreover, those servers have to be cool. And I don't mean wearing a pair of Ray-Bans, a spiffy hat with a cigarette dangling. Those servers need air conditioning all of the time.
Here's the point: the small things we do mindlessly, consume energy constantly. And no matter how conservation minded we would like to be, are we really willing to give up the pleasure and utility of modern technology. Laptop users consume a shopowner's electricity and WiFi because it's "free" but it should be as carefully conserved as if it were your own. The proprietor meets his overhead by selling food and drink; the freebies are an inducement to buy.
So, I'll quote the wisdom of my literary agent, Amanda Mecke: "There is no free lunch --- or electricity anywhere."
It points up how oblivious we all are to our use of energy both direct and indirect. When we use the internet we either have a desktop plugged in, a laptop we have had to charge up or some other portable device that also had to be charged. But we speak with forked tongue: We speak conservation and renewables out of one side of our mouths and banter about this great, energy consuming technology out of the other side.
Remember, the internet isn't in the airwaves because angels deliver it on splendid wings. There are servers, mountains of servers, all over the world that provide us with the internet. And they require power. Lots of it. Moreover, those servers have to be cool. And I don't mean wearing a pair of Ray-Bans, a spiffy hat with a cigarette dangling. Those servers need air conditioning all of the time.
Here's the point: the small things we do mindlessly, consume energy constantly. And no matter how conservation minded we would like to be, are we really willing to give up the pleasure and utility of modern technology. Laptop users consume a shopowner's electricity and WiFi because it's "free" but it should be as carefully conserved as if it were your own. The proprietor meets his overhead by selling food and drink; the freebies are an inducement to buy.
So, I'll quote the wisdom of my literary agent, Amanda Mecke: "There is no free lunch --- or electricity anywhere."
Saturday, July 11, 2009
CONGRESS RESTORES FUNDING FOR HYDROGEN FUEL CELLS
Finally, some sanity from the Congress. Steven Chu, Secretary of Energy, killed fuel cell research a while back. Now it has been restored (MIT Technology Review: Hydrogen Fuel Cell Funding Restored) by the legislature, you know, that bicameral body that sits in session on our behalf in the District.
Secretary Chu prefers biofuels and better batteries, but that is not mainstream thinking. Thinking long into the future, hydrogen-based fuel cells make a lot of sense. In the interim, fossil fuel-based fuel cells--methanol for automotive propulsion and diesel and natural gas (among others) for stationary fuel cells--should be aggressively developed by Dr. Chu and the DOE.
There will come a day when planet earth can yield up no more hydrocarbons. Our planet is finite. At that time, the hydrogen-based fuel cell (hydrogen cracked from water), fully developed and ready to go, will displace the interim technology. We need to be fully prepared for the hydrogen future--a world in which all electricity is generated by nuclear power plants and all hydrogen comes from the oceans. A time when there is no measurable air pollution, greenhouse gases and the insidious effects of mercury and arsenic from burning coal.
And thank you to Amanda Mecke, my literary agent, for kindly passing on this article to me.
Secretary Chu prefers biofuels and better batteries, but that is not mainstream thinking. Thinking long into the future, hydrogen-based fuel cells make a lot of sense. In the interim, fossil fuel-based fuel cells--methanol for automotive propulsion and diesel and natural gas (among others) for stationary fuel cells--should be aggressively developed by Dr. Chu and the DOE.
There will come a day when planet earth can yield up no more hydrocarbons. Our planet is finite. At that time, the hydrogen-based fuel cell (hydrogen cracked from water), fully developed and ready to go, will displace the interim technology. We need to be fully prepared for the hydrogen future--a world in which all electricity is generated by nuclear power plants and all hydrogen comes from the oceans. A time when there is no measurable air pollution, greenhouse gases and the insidious effects of mercury and arsenic from burning coal.
And thank you to Amanda Mecke, my literary agent, for kindly passing on this article to me.
Sunday, May 17, 2009
China Outpaces U.S. in Cleaner Coal-Fired Plants
My literary agent, Amanda Mecke, sent me an article with the same title as this blog post. The essence of it is the following quotations:
"While the United States is still debating whether to build a more efficient kind of coal-fired power plant that uses extremely hot steam, China has begun building such plants at a rate of one a month."
"With greater efficiency, a power plant burns less coal and emits less carbon dioxide for each unit of electricity it generates. Experts say the least efficient plants in China today convert 27 to 36 percent of the energy in coal into electricity. The most efficient plants achieve an efficiency as high as 44 percent, meaning they can cut global warming emissions by more than a third compared with the weakest plants."
What they are talking about is supercritical (extremely hot steam) coal fired plants and the quotations are true. I am currently, personally involved in financing two of these plants in the United States. The problem is twofold: (1) The Congress has put a moratorium on the financing of Coal Fired Plants by the Department of Agriculture's Rural Utility Service. This prevents Rural Ekectric Cooperatives in this country from accessing government loans to build these coal fired plants. That's why I am involved, providing private funds to finance what the government (led by Harry Waxman) will not. (2) Most of those in the government making these decisions do not know the difference between a conventional coal fired plant and a supercritical one.
The average coal unit in the U.S. has about a 33% efficiency. Increasing efficiencies to 44%, as the article states, would eliminate one third of all of the carbon dioxide emitted by the existing coal plant fleet.
That means we can have it all: Coal fired power plants with less pollutants across the board. All we need in our government is knowledge, reason, cooperation and less dogma from radical environmentalists. This can transition the U.S. over a reasonable period of time to non-polluting (or much less polluting) technologies.
"While the United States is still debating whether to build a more efficient kind of coal-fired power plant that uses extremely hot steam, China has begun building such plants at a rate of one a month."
"With greater efficiency, a power plant burns less coal and emits less carbon dioxide for each unit of electricity it generates. Experts say the least efficient plants in China today convert 27 to 36 percent of the energy in coal into electricity. The most efficient plants achieve an efficiency as high as 44 percent, meaning they can cut global warming emissions by more than a third compared with the weakest plants."
What they are talking about is supercritical (extremely hot steam) coal fired plants and the quotations are true. I am currently, personally involved in financing two of these plants in the United States. The problem is twofold: (1) The Congress has put a moratorium on the financing of Coal Fired Plants by the Department of Agriculture's Rural Utility Service. This prevents Rural Ekectric Cooperatives in this country from accessing government loans to build these coal fired plants. That's why I am involved, providing private funds to finance what the government (led by Harry Waxman) will not. (2) Most of those in the government making these decisions do not know the difference between a conventional coal fired plant and a supercritical one.
The average coal unit in the U.S. has about a 33% efficiency. Increasing efficiencies to 44%, as the article states, would eliminate one third of all of the carbon dioxide emitted by the existing coal plant fleet.
That means we can have it all: Coal fired power plants with less pollutants across the board. All we need in our government is knowledge, reason, cooperation and less dogma from radical environmentalists. This can transition the U.S. over a reasonable period of time to non-polluting (or much less polluting) technologies.
Saturday, May 9, 2009
NY Times: U.S. Drops Fuel Cell Research
"Developing those cells and coming up with a way to transport the hydrogen is a big challenge, Energy Secretary Steven Chu said in releasing energy-related details of the administration’s budget for the year beginning Oct. 1. Dr. Chu said the government preferred to focus on projects that would bear fruit more quickly."
The above quotation from the Times of May 7th demonstrates how misguided and disconnected bureaucrats and elected officials are from the real world of energy. Transporting hydrogen has never been a good idea. Why are they even thinking about it?
On March 9, 2009, only two months ago, the following news was released by the Department of Energy:
"Solid Oxide Fuel Cell Successfully Powers Truck Cab and Sleeper in DOE-Sponsored Test
DOE, Delphi, Peterbilt Join to Test Auxiliary Power Unit for Commercial Trucks"
The fuel cell was constructed by Delphi Corporation and ran on straight-from-the-pump diesel fuel. The release went on to say, "The unit is compact and can be configured to use natural gas, bio-diesel, propane, gasoline, coal-derived fuel, or military logistics fuel."
If Dr. Chu and our government would like to focus on projects that will bear fruit more quickly, they need to start paying attention to their own research apparatus at the DOE and the money tax payers are spending on this really outstanding research.
The current liquid fuels transportation infrastructure can support fuel cells run on methanol and diesel. This is the future of automotive propulsion.
The above quotation from the Times of May 7th demonstrates how misguided and disconnected bureaucrats and elected officials are from the real world of energy. Transporting hydrogen has never been a good idea. Why are they even thinking about it?
On March 9, 2009, only two months ago, the following news was released by the Department of Energy:
"Solid Oxide Fuel Cell Successfully Powers Truck Cab and Sleeper in DOE-Sponsored Test
DOE, Delphi, Peterbilt Join to Test Auxiliary Power Unit for Commercial Trucks"
The fuel cell was constructed by Delphi Corporation and ran on straight-from-the-pump diesel fuel. The release went on to say, "The unit is compact and can be configured to use natural gas, bio-diesel, propane, gasoline, coal-derived fuel, or military logistics fuel."
If Dr. Chu and our government would like to focus on projects that will bear fruit more quickly, they need to start paying attention to their own research apparatus at the DOE and the money tax payers are spending on this really outstanding research.
The current liquid fuels transportation infrastructure can support fuel cells run on methanol and diesel. This is the future of automotive propulsion.
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