A team of scientists from Boston College and Duke University has developed a highly-engineered metamaterial capable of absorbing all of the
light that strikes it – to a scientific standard of perfection – they report in Physical Review Letters.
The team designed and engineered a metamaterial that uses tiny geometric surface
features to successfully capture the electric and magnetic properties of a microwave to the point of total absorption.
“Three things can happen to light when it hits a material,” says Boston College Physicist Willie J. Padilla. “It can be reflected, as in a mirror. It can be
transmitted, as with window glass. Or it can be absorbed and turned into heat. This metamaterial has been engineered to ensure that all light is neither reflected nor transmitted, but is turned completely into heat and absorbed. It shows we can design a metamaterial so that at a specific frequency it can absorb all of the photons that fall onto its surface.”
FURTHER READING
The Physics letters article is hereWe present the design for an absorbing metamaterial (MM) with near unity absorbance A. Our structure consists of two MM resonators that couple separately to electric and magnetic fields so as to absorb all incident radiation within a single unit cell layer. We fabricate, characterize, and analyze a MM absorber with a slightly lower predicted A of 96%. Unlike conventional absorbers, our MM consists solely of metallic elements. The substrate can therefore be optimized for other parameters of interest. We experimentally demonstrate a peak A greater than 88% at 11.5 GHz.
June 03, 2008
New Metamaterial a “Perfect” Absorber of Light
May 20, 2008
Some of T Boone Pickens oil predictions are wrong
T Boone Pickens has made various predictions about oil on MCNBC
"Eighty-five million barrels of oil a day is all the world can produce, and the demand is 87 million," he said. "It's just that simple. It doesn't have anything to do with the value of the dollar."
target=blank>Pickens founded BP Capital and has a 46% interest in the company which runs two hedge funds, Capital Commodity and Capital Equity, both of which invest primarily in oil and natural gas.
Pickens is also investing in wind energy
Pickens says that world oil production will not exceed 85 million bpd. The EIA says that Feb 2008, the world production is at 85.921 million bpd. March and April had 300,000 bpd increase from Saudi Arabia and 42,000 bpd increases in Brazil.
The IEA statistics for total world oil production rose to 87.47 million b/d in February, up from 87.29 million b/d in January, the IEA said, thanks to higher volumes from the Americas and the former Soviet Union.
It would appear by end of 2008, Thunder Horse (Gulf of Mexico deepwater oil rig) will come online in 2008 and produce 250,000 bpd sometime in 2009. More additions in Saudi Arabia in July. More increases in Brazil up to 500,000-600,000 bpd more by end of 2008.
I predict that Pickens is wrong on the production peak.
I predict that the May, 2008 EIA numbers will be 86+ million bpd. (Not April because of the UK strike and other issues in April)
I predict that the Sept, 2008 EIA numbers will be 87+ million bpd.
On the Oilsands
Pickens claimed that the oilsand development would be hindered by a shortage of welders and personnel.
When asked about Canadian Oil sands, he said he had $500 million invested in this segment. He has been there ten years. I pointed out that he has probably made five times on his investment and he agreed. He owns Canadian Oil Sands (CNQ) and Suncor (SU). I then asked him if he was worried about the fact that the Canadian government is going to raise taxes. He said that governments always tax profitable businesses. Chesapeake Energy (CHK) and SandRidge (SD) were two explorers that he mentioned.
Encana is projecting growth in their holdings in the Alberta oilsands from 35,000 barrels a day net to EnCana today to 100,000 next year (2009), to 200,000 by 2012 and to 400,000 barrels a day by 2016.
A third-quarter [2008] startup of the massive Horizon oilsands project will deliver 110,000 barrels per day (bpd) in the first phase. Construction to increase capacity to 250,000 bpd is already underway.
Pickens forecasts $150 a barrel price for oil in 2008
"The only way I see that oil doesn't continue to rise [is] if we had a global recession." he said. "That will happen at some point, but I don't see the Chinese stumbling until after the Olympics."
Pickens says natural gas is the only American resource that can reduce oil imports. He claims the effective use of natural gas could reduce oil imports by 40 percent. [Wind and solar can free up natural gas to replace 40% of oil use in the US within 10 years.] He dismissed ethanol as an alternative.
Prices could rise that high because of a weak dollar, supply/demand imbalance, and any hickup in production (like the Nigerian unrest that is blocking 500,000 to 1 million bpd).
Using nuclear power, wind and solar to free up natural gas would be part of a reasonable energy plan.
April 30, 2008
Solar power breakthroughs SUNRGI 7 cents per kwh 2009 and Israel Solar Power 100 times lower cost
SUNRGI's "concentrated photovoltaic" system relies on lenses to magnify sunlight 2,000 times, letting it produce as much electricity as standard panels with a far smaller system. They say they'll start producing solar panels by mid-2009 that will generate electricity for about 7 cents a kilowatt hour, including installation.
Update: Very cool: Dilbert blog [Scott Adams] has linked to this article.
In terms of Scott Adams idea that Israel with 100 times cheaper solar power could break the Middle East oil stranglehold. The Israeli government announced its support for a broad effort to promote the use of electric cars, embracing a joint venture between an American-Israeli entrepreneur and Renault, of France, and its partner, Nissan Motor, of Japan. The idea, said Shai Agassi, 39, the software entrepreneur behind the new company, is to sell electric car transportation on the model of the cellphone. Purchasers get subsidized hardware - the car - and pay a monthly fee for expected mileage, like minutes on a cellphone plan, eliminating concerns about the fluctuating price of gasoline.
Part of the global effort is the development of ultrabattery (cheaper, higher performance, longer lasting battery/supercapacitor combinations.
Solar panels generate electricity when photons in sunlight knock loose electrons in silicon or another semiconductor. Other concentrated photovoltaic makers magnify sunlight about 500 times. SUNRGI says it can multiply that by four because it has a system to instantly cool its germanium-based semiconductor from 3,300 degrees to 20 degrees above ambient temperature. High temperatures can melt a solar cell.
Also pushing down costs are a highly efficient semiconductor that converts 37% of the sunlight to electricity, more than double the industry average. The unit's compact size allows it to be made at electronics or PC factories, avoiding the need to build new plants.
SUNRGI technology is discussed in greater detail at their website.
SUNRGI panels
A DIFFERENT DEVELOPMENT
Scientists at the University of Tel Aviv in Israel claim they have found a way to construct efficient photovoltaic cells costing at least a hundred times less than conventional silicon based devices, and with 25% energy conversion efficiency.
The reactive element in the researchers' patent pending device is genetically engineered proteins using photosynthesis for production of electrical energy. They also claim that PS I generates a stable charge separation in 200 ns across 6 nm of protein to generate an electric potential of 1 V with quantum efficiency of 1 and absorbed energy conversion efficiency of 47 percent. A further advantage of PS I is said to be its transparency to infrared radiation, which eliminates the need for expensive cooling equipment.
The researchers include Prof. Chanoch Carmeli, Dr. Shachar Richter, Dr. Itai Carmeli and Prof. Yossi Rosenwaks. Ramot, Tel Aviv Universitys technology transfer company, is set to help commercialize the invention.
Larry Loev, director of business development for high technologies at Ramot told EETimes the low cost of the proposed device is based on the low cost of PS I in comparison to silicon. While one square meter of PS I should cost around $1, a similar area made of silicon should cost around $200.
RELATED NEWS
Coolearth's concentrated solar power balloons is my favorite for solar power. SUNRGI appears to be ahead by a few months to a couple of years. Nanosolar and Coolearth concentrated solar balloons are being deployed to municipal and rural areas.
The overall energy plan that I would recommend In the big energy picture solar power is tiny and even with these breakthroughs will take time to have a major impact. Plus without cheap power storage solar is not base load power.
For wind power, kitegen is a more promising architecture
Generation of fuel from algae is the best bet for a lot of efficient biofuel
Nuclear power can and will have far more positive impact than most people believe.
This article points how much risk there is for each energy source and show how rooftop solar can cause more deaths than Chernobyl. The solar options above SUNRGI, the protein pools and Coolearth are installed on the ground.
April 28, 2008
Vasimr 200KW almost flight ready in 2008 and the solar electric sail like a Dandelion seed
I will look at two near term space systems the Vasimr and the solar electric sail. Both could provide a significant increase in the performance of various space missions. Both have their advantages and would be welcome improvements in the capabilities of space systems. Vasimr can go up to higher power levels that are limited by the Vasimr system and the power system. The Solar electric sail uses no propellant while the Vasimr is ten times or more efficient than current chemical systems. Both could be in space flight tests in the next year or three.
The 200 kilowatt VX200 Vasimr system is almost ready for flight tests and the type of missions impacts it would have are discussed. The solar electric sail system which I reviewed last week is discussed again. Comparison is made to dandelion seeds and how the multiple parachute configuration could be used to combine the propulsion of several solar electric sails to move larger objects.
The 200 kilowatt Vasimr plasma engine is expected to reach NASA's technology readiness level 6 in 2008 An initial test firing of the full engine
prototype has been postponed until the 2nd quarter of 2008 in order to give Scientific Magnetics of Culham, UK. the needed time to complete its certification of the superconducting subsystem.
A 12 MW Vasimr system could send a ship to Mars in less than 120 days one way. A 200 MW Vasimr could go to Mars in 39 days.
1-2MW Vasimr lunar cargo vehicle could transfer up to 39% of the mass from low earth orbit to the moon.
The 6 page study of a Vasimr powered lunar cargo vehicle. Five of the 200 kilowatt Vasimr engines could make up a 1 MW plasma powered vehicle.
March 17, Alliant Techsystems (NYSE: ATK) [$4.1 billion company] and the Ad Astra Rocket Company of Houston, Texas signed and executed a Technology
Development Alliance to explore future in-space propulsion systems for lunar and planetary missions.
VASIMR versus the Solar electric Sail
A VASIMR system can get up to 300 kilometers/second and faster while the solar electric sail goes 100 kilometers/second. Both systems could be improved beyond those performance levels. The variable specific impulse magnetoplasma rocket (VASIMR) uses radio waves and magnetic fields to accelerate a propellant. Current VASIMR designs should be capable of producing specific impulses ranging from 10,000-300,000 m/s (1,000-30,000 seconds) - the low end of this range is comparable to some ion thruster designs. 
I was noticing how much like a dandelion seed the solar electric sail system would be. The solar electric sail would be blown by the solar wind.
I also believe that the solar electric sail could have multiple sails attached to one vehicle like a multiple parachute system.
Technology Readiness levels [6-9]
6. System/subsystem model or prototype demonstration in a relevant environment: Representative model or prototype system, which is well beyond the breadboard tested for TRL 5, is tested in a relevant environment. Represents a major step up in a technology's demonstrated readiness. Examples include testing a prototype in a high fidelity laboratory environment or in simulated operational environment.
7. System prototype demonstration in an operational environment Prototype near or at planned operational system. Examples include testing the prototype in a test bed aircraft.
8. Actual system completed and 'flight qualified' through test and demonstration.
9. Actual system 'flight proven' through successful mission operations.
They are expecting to get to a flight test in 2010.
April 24, 2008
Solar Thermal Municipal Power
Nanosolar CEO Martin Roscheisen is focusing on municipal solar power plants of 2 - 10 megawatts in size.
Companies have come to realize that they can avoid most of the bureaucratic snags involved in building plants that produce over 50 megawatts. Furthermore, by grouping their panels into small lots, they’ve been able to grab small tracts of land on the edges of cities and towns, or on land that can be dual-purposed like farms. A secondary advantage is the ability to hook into the existing power grid without the modifications required to channel power from a large plant.
The idea is to build 10 acre lots on the outskirts of small cities that could feed into the municipal power grid directly. Each lot, consisting of several rows of solar panels mounted on rails above ground, could provide up to 2 megawatts, enough to serve 1,000 homes. The panels would be mounted on rails to prevent them from affecting the surrounding wildlife and vegetation. Nanosolar has gotten plenty of attention for its claim that it can sell its cells for as low as 99 cents per watt, low enough to be competitive with non-renewable energy sources, as well as recently raising over $50 million more from EDF Energies Nouvelles.
Coolearth solar who I recently covered claims that they will produce electricity for 18 cents a watt, and hopes to ramp up its production of balloon concentrators to 50 megawatts by next year (2009).
Coolearth Solars target is 29 cents per watt INSTALLED by 2010. 18 cents per watt for materials. 18 cents / Wattp (Watt panel)
CoolEarth Solar's plans
FY07+ - 10-50 kW installations
FY08+: 50 kW - 1 MW installations
FY10+: 1-10 MW Micro-utility franchises
There are several solar thermal companies and some are described by Al Fin
SolFocus, for example, makes large solar concentrator panels, which use mirrors to focus more light onto highly efficient solar photovoltaics. It raised $63.6 million.
April 21, 2008
Concentrated solar power balloons
Giant solar energy balloons floating high in the air may be a cheap way to provide electricity to areas lacking the land and infrastructure needed for traditional power systems. Solar balloons, designed by a team from the Technion Institute of Technology, could be used to harness the sun's energy in those remote areas. However, the Coolearth concentrated solar power balloon concept which is described after the Israeli plan is far better. Coolearth is targeting a cost 25 times less than regular solar PV.
The helium-filled balloons, covered with thin solar panels, hover as high as a few hundred metres in the air, and are connected via a wire cable to an inverter, which converts the electricity into a form households can use.
It will be about a year before the system is ready, Gurfil said. But initial research, both computerised and using a crude prototype, showed a balloon with a three metre (10 ft) diameter could provide about one kilowatt of energy, the same as 25 square metres (269 square feet) of traditional solar panels. While 25 square metres of traditional solar panels may cost about $10,000, the target cost of the balloon is less than $4,000.
Another company that is working on solar concentrating balloons is Coolearth. The Coolearth approach looks superior. Coolearth was funded for $21 million. There advantages are inflatable mirrors are 400 times cheaper than polished aluminum mirrors and their rigging uses about 60 times less steel than truss work and with minimal grounds preparation.
Here is a diagram of coolearth's system.
Each balloon, measuring two meters (6 1/2 feet) in diameter, can generate 500 watts of electricity and will eventually cost less than $2. With low maintenance and replacement costs, he believes the system will significantly reduce the cost of solar energy from the current price of around $4 per watt of installed capacity to levels where is competes directly with fossil fuel-based energy sources. They are confident that their minimum-material design and use of commodity materials will cut the cost of photovoltaic electricity in a 1 megawatt installation to 29 cents per watt by 2010. They want to install on farms. The advantages of installing in rural areas is the abundance of land that is easy to access and maintain (far easier than up on a rooftop), the ease of setting up large power plants (at roughly eight acres per megawatt of electricity.
FURTHER READING
Some background on concentrated solar power
OTHER ENVIRONMENTAL READING
Making homes more energy efficient with better water heaters. Could save 2400 kwh our of the total 11000 kwh used by an average US household. Better and cheaper than rooftop solar and would work well with concentrated solar balloons and other power sources.
Kitegen is the best potential wind power generation system
Electric and hybrid motorcycles and scooters
April 16, 2008
Solar Wind Electric Sail Propulsion planning test mission
A simplified picture of the electric sail. An actual system would have 50 to 100 or more 20 kilometer wires. 100 kg spaceships could be accelerated to final speeds of 40-100 km/second. The electric sail is an extremely promising new propulsion technique which is nearly ready to be tested. If electron heating turns out to be successful performance may be increased even more. Costs for solar system missions will go down and new capabilities and performance will be possible.
The electric solar wind sail developed at the Finnish Meteorological Institute two years ago has moved rapidly from invention towards implementation. The main parts of the device are long metallic tethers and a solar-powered electron gun which keeps the tethers positively charged. The solar wind exerts a small but continuous thrust on the tethers and the spacecraft.
"We haven't encountered major problems in any of the technical fields thus far. This has already enabled us to start planning the first test mission,” says Dr. Pekka Janhunen. An important subgoal was reached when the Electronics Research Laboratory of the University of Helsinki managed to develop a method for constructing a multiline micrometeoroid-resistant tether out of very thin metal wires using ultrasonic welding. The newly developed technique allows the bonding together of thin metal wires in any geometry; thus, the method might also have spinoff applications outside the electric sail.
The electric sail could enable faster and cheaper solar system exploration. It might also enable economic utilisation of asteroid resources for, e.g. producing rocket fuel in orbit.
Deploying the wiresAn ideal (i.e. fully reflecting) solar sail receives a radiation pressure force of 9μN/m2 at 1AU distance from the Sun. Let us calculate how thin a solar sail should be, to reach the same specific acceleration as an electric sail wire plus electron gun subsystems. Using an 82 km/s final speed, one obtains that the solar sail should have an areal density of 1.1 g/m**2, which translates to 200 nm thickness if the material is aluminium and 50% of the mass is assumed to go to support structures. This is 5–10 times thinner than present technology.
The electric sail resembles the solar sail in that it provides small but inexhaustible thrust which is directed outward from the Sun, with a modest control of the thrust direction allowed (probably by a few tens of degrees). Some possible missions:
1. Missions going outward in the solar system and aiming for >50 km/s final speed, such as missions going out of the heliosphere and fast and cheap flyby missions of any target in the outer solar system. 2-4 years to Pluto instead of 10 years with chemical rockets and gravity slingshots.
2. By inclining the sail to some angle it can also be used to spiral inward in the solar system to study e.g. Mercury and Sun. Also a nonzero inclination with respect to the ecliptic plane is possible to achieve which may be beneficial for observing the Sun. Also the return trip back to Earth from the inner solar system is possible, as is cruising back and forth in the inner solar system and visiting multiple targets such as asteroids.
3. the electric sail could be used to implement a solar wind monitoring spacecraft which is placed permanently between Earth and Sun at somewhere else than the Lagrange point, thus providing a space weather service with more than one hour of warning time. Propulsion and data taking phases probably must be interleaved because ion measurements are not possible when the platform is charged to high positive voltage, although the plasma density and dynamic pressure of the solar wind can probably be sensed by an electron detector and accelerometer even when the electric sail voltage is turned on.
4. Once accelerated to a high outward speed an electric sailing spacecraft cannot by itself stop to orbit a remote target because the radial component of the thrust is always positive. For stopping under those circumstances one has to use aerocapture or some other traditional technique. Although the electric sail does not provide a marked speed benefit for such missions, being propellantless it might still provide cost saving; this remains to be studied. In interstellar space the plasma flow is rather slow. Thus the electric sail cannot be used for acceleration, but it can instead be used for braking the spacecraft.
5. It might also provide cheap transportation of raw materials such as water mined from asteroids and used for in-situ fuel making at high Earth orbit.
March 14, 2008
Deaths per TWh for all energy sources: Rooftop solar power is actually more dangerous than Chernobyl
Comparing deaths/TWh for all energy sources
Update: A superior form of solar power would be the Coolearth concentrated solar power system which would be installed on the ground or wires over a ground installation.
The ExternE calculation of death/TWh from different energy sources (not including global warming effects and is the average for European nations). 
This draws on data from 4290 energy-related accidents, 1943 of them classified as severe, and compares different energy sources. It considers over 15,000 fatalities related to oil, over 8000 related to coal and 5000 from hydro.
Deaths statistics from the fuel chain for coal and nuclear
Higher level of deaths from coal in public health would be related to the increased deaths from particulates. The deaths totals are more from coal occupation are mining.
The World Health Organization and other sources attribute about 1 million deaths/year to coal air pollution. Coal generates about 6200 TWh out of the world total of 15500 TWh of electricity. This would be 161 deaths per TWh.
In the USA about 30,000 deaths/year from coal pollution from 2000 TWh. 15 deaths per TWh.
In China about 500,000 deaths/year from coal pollution from 1800 TWh. 278 deaths per TWh.
The construction of existing 1970-vintage U.S. nuclear power plants required 40 metric tons (MT) of steel and 190 cubic meters (m3) of concrete per average megawatt of electricity (MW(e)) generating capacity. For comparison, a typical wind energy system operating with 6.5 meters-per-second average wind speed requires construction inputs of 460 MT of steel and 870 m**3 of concrete per average MW(e). Coal uses 98 MT of steel and 160 m**3 of concrete per average MW(e); & natural-gas combined cycle plants use 3.3 MT steel and 27 m**3 concrete.
Wind power generation was 95 GW at the end of 2007.
1 MW produces 3,066 MWh if 35% efficient.
20 GW in Germany generated 30 TWh in 2006.
95GW would be generating about 150TWh.
95000GW would have taken 43.7 million tons of steel and 82.7 million tons of concrete. 3% of one year of global steel production. 4% of one year of the world’s concrete production. Half of one year’s production in the US for steel. About 15 deaths if corresponded to half of one years metal/nonmetal mining fatalities. 0.1 deaths per TWh. If the metal and concrete had come from China about 2700 metal/nonmetal mining deaths per year for 5 times the amount of steel. 270 deaths to get the metal for the wind turbines. 1.9 deaths per TWh. These construction related deaths are amortized over the life of the wind turbines of 30 years. Other wind power deaths need to factor in dangers associated with working with very tall structures (50 stories tall) and with deep water work associated with building and anchoring offshore. Wind power proponent and author Paul Gipe estimated in Wind Energy Comes of Age that the mortality rate for wind power from 1980–1994 was 0.4 deaths per terawatt-hour. Paul Gipe's estimate as of end 2000 was 0.15 deaths per TWh, a decline attributed to greater total cumulative generation. By comparison, hydroelectric power was found to to have a fatality rate of 0.10 per TWh (883 fatalities for every TW·yr) in the period 1969–1996. This includes the Banqiao Dam collapse in 1975 that killed thousands.
Metal/Nonmetal fatalities in the USA (iron and concrete components mainly)
(3.1 GWp generated 2TWh in Germany for solar)
Coal and fossil fuel deaths usually do not include deaths caused during transportation. The more trucking and rail transport is used then the more deaths there are. The transportation deaths are a larger component of the deaths in the USA than direct industry deaths. Moving 1.2 billion tons of coal takes up 40% of the freight rail traffic and a few percent of the trucking in the USA.
Uranium mining is a lot safer because insitu leaching (the main method of uranium mining) involves flushing acid down pipes. No workers are digging underground anymore. Only about 60,000 tons of uranium are needed each year so that is 200 times less material being moved than for coal plants.
But what about Chernobyl ?
The World Health Organization study in 2005 indicated that 50 people died to that point as a direct result of Chernobyl. 4000 people may eventually die earlier as a result of Chernobyl, but those deaths would be more than 20 years after the fact and the cause and effect becomes more tenuous.
He explains that there have been 4000 cases of thyroid cancer, mainly in children, but that except for nine deaths, all of them have recovered. "Otherwise, the team of international experts found no evidence for any increases in the incidence of leukemia and cancer among affected residents."
Averaging about 2100 TWh from 1985-2005 or a total of 42,000 TWh. So those 50 deaths would be 0.0012 deaths/TWh. If those possible 4000 deaths occur over the next 25 years, then with 2800 TWh being assumed average for 2005 through 2030, then it would be 4000 deaths over 112,000 TWh generated over 45 years or 0.037 deaths/TWh. There are no reactors in existence that are as unsafe as the Chernobyl reactor was. Even the eight of that type that exist have containment domes and operate with lower void co-efficients.
The safety issues with Rooftop solar installations
Those who talk about PV solar power (millions of roofs) need to consider roof worker safety. About 1000 construction fatalities per year in the US alone. 33% from working at heights.
Falls are the leading cause of fatalities in the construction industry. An average of 362 fatal falls occurred each year from 1995 to 1999, with the trend on the increase. 269 deaths (combined falls from ladders and roofs in 2002). UPDATE: Based on a more detailed analysis of the fatal fall statistic reports I would now estimate the fatal falls that would match the solar panel roof installations as 100-150. Only 30-40 are classified as being a professional roofer but deaths for laborer or general construction worker or a private individual count as deaths.
Roofing is the 6th most dangerous job. Roofers had a fatality rate in 2002 of 37 per 100,000 workers.
In 2001, there were 107 million homes in the United States; of those, 73.7 million were single-family homes. Roughly 5 million new homes are built each year and old roofs need to significant work or replacement every 20 years. So 9-10 million roofing jobs in the US alone. In 2007, Solar power was at 12.4 GW or about 12.6 TWh. The 2006 figure for Germany PV was only 1TWh from about 1.5GW from $4 billion/yr. The German rate of solar power generation would mean 12.4GW would generate 8TWh. 2.8GW generates 2 TWh for Germany, assuming other places are 50% sunnier on average, then the 9.6GW would generate 10.6 TWh.
$4 billion is about the cost of one of the new 1.5 GW nuclear power plants, which would generate 12 TWh/year. Nuclear power plants (104) rated at a total 100GW generated 800 Twh in 2007.
The world total was from about 1.5 million solar roofed homes. 30% of the solar power was from roof installed units. 1/6th of the 9 million roofing job accidents would be about 50 deaths from installing 1.5 million roofs if other countries had similar to US safety. The amount of roof installations is increasing as a percentage. 4 TWh from roofs PV. So 12.5 deaths per TWh from solar roof installations. Assuming 15 years as the average functional life or time until major maintenance or upgrade is required. The average yearly deaths from rooftop solar is 0.83/TWh. Those who want a lower bound estimate can double the life of the solar panels (0.44deaths/TWh). This is worse than the occupational safety issues associated with coal and nuclear power. (see table below). 12 to 25 times less safe than the projected upper bound end effect of Chernobyl (from WHO figures). The fifty actual deaths from roof installation accidents for 1.5 million roof installations is equal to the actual deaths experienced so far from Chernobyl. If all 80 million residential roofs in the USA had solar power installed then one would expect 9 times the annual roofing deaths of 300 people or 2700 people (roofers to die). This would generate about 240 TWh of power each year. (30% of the power generated from nuclear power in the USA). 90 people per year over an optimistic life of 30 years for the panels not including maintenance or any electrical shock incidents.
Maintenance and Functional life of solar panels
[Q26. Do they require any maintenance?
A26: Only an occasional wipe to ensure optimal performance of the solar panel.]
15. How long will the panels last?
Generally, systems last 20-30 years since the waterproof seals on the panels tend to deteriorate over time.
16. If I move home, can I take the solar panels with me?
You could take your solar power system down and re-install it at your new house provided the roof of the new house is suitable. Or, you could include it in the selling price of your house. If your house is in a remote area and the solar power system is the sole source of power, the purchaser of your house would be wise to make sure the solar power system is included in the price, or they’ll be left without electricity.
[Generally hail resistant but a storm big enough to damage a regular roof would also damage a rooftop solar panel system.]
http://www.gepower.com/prod_serv/products/solar/en/faqs/resid_sys.htm#faq24
http://www.gepower.com/prod_serv/products/solar/en/faqs/resid_sys.htm#faq28http://www.heatmyhome.co.uk/pv-solar-panels.htm
The 10 most dangerous jobs
Occupation Fatalities per 100,000
Timber cutters 117.8
Fishers 71.1
Pilots and navigators 69.8
Structural metal workers 58.2
Drivers-sales workers 37.9
Roofers 37
Electrical power installers 32.5 [also, solar power related]
Farm occupations 28
Construction laborers 27.7
Truck drivers 25
Source: Bureau of Labor Statistics; survey of occupations with minimum 30 fatalities and 45,000 workers in 2002
Conclusion:
Nothing is perfectly safe. Chasing perfection can cause us to ignore just improving and trading worse for a lot better. Non-roof installations of solar is safer than roof installation. Nuclear, wind, non-roof solar and hydro are a lot safer than coal and oil. Natural gas is safer but not as much as nuclear and those others. The focus needs to be on getting rid of the most dangerous energy sources which are coal and oil first. Then after that decades long project is done to look at the other energy sources. Safety and improvements for all energy sources should be made as we go.
UPDATE:
Rooftop solar is still a hundred times safer than coal and oil power because of air pollution deaths. Other ways to make solar power safer:
1. Increase safety for all rooftop work (can reduce deaths by half or more)
2. Rooftop solar tiles installed on new buildings might not have any more incremental deaths as opposed to panels that are separate from the roof tiles or systems installed that replace roof tiles before they would normally be replaced.
3. Create some new installation system where people stay on the ground using some forklift or crane to raise and place a solar power system onto a roof. Have to ensure that the heavy machinery system is safer than the roofing process being replaced.
Some responders online are in denial that people who work on a roof can fall off regardless of the reason they went up there. If I go up there to replace roofing tiles or go up there to install solar panels, the risk of falling is pretty much the same especially when the number of times being compared heads to large numbers like millions of times for each. As I noted in the comments, statistics show that 70% of fatal construction falls occur at height of 3 stories or less.
Some have also claimed that someone who went up onto a roof to install a solar panel but then fell is not a death associated with solar power. Similarly then if someone is killed in a coal mine then that is not a coal power death because the coal was not in the power plant yet or they might have some other reason for being underground and would have been crushed anyway.
FURTHER READING
189 page pdf from the 1997 Externe analysis of energy sources and fuel cycles.
RELATED NEWS
Canada is increasing the planned number of nuclear reactors in Alberta to 4 plants generating 4 GW. The plan is to complete them by 2017.
Southern California Edison (SCE) plans to spend $875 million over the next five years putting solar panels onto commercial roofs to generate 250 megawatts of solar capacity. The panels will be on 65 million square feet of roof.
San Jose has a 15 year green vision to install 100,000 solar power roofs.
San Jose was chosen a Solar America City by the U.S. Department of Energy and will share $2.4 million in funding with 11 other cities. Other cities designated as Solar America Cities include Sacramento, Santa Rosa, Seattle, Wash.; Houston, Texas; Knoxville, Tenn.; Milwaukee, Wis.; Minneapolis & St. Paul, Minn.; Orlando, Fla.; Philadelphia, Penn.; and San Antonio, Texas.
Severin Borenstein, director of the U.C. Energy Institute and a professor at the University of California, Berkeley's business school, called existing technology "a loser" in a research paper. "We are throwing money away by installing the current solar PV technology," he said.Borenstein calls for more state and federal money to be spent on research into better technology, rather than on subsidies for residential solar power systems. In his analysis, Borenstein found that a typical PV system costs between $86,000 and $91,000 to install, while the value of its power over its lifetime ranges from $19,000 to $51,000. Even assuming a 5 percent annual increase in electric costs and a 1 percent interest rate, the cost of a PV system is 80 percent greater than the value of the electricity it will produce. In his paper, Borenstein also factored in the value of greenhouse gas reductions into his calculations, and found that at current prices the PV technology still doesn't deliver.
California's Million Solar Roofs Plan, signed into law in 2006, which will provide 3,000 megawatts of additional clean energy and reduce the output of greenhouse gases by 3 million tons. The 2.9-billion-dollar incentive plan for homeowners and building owners who install solar electric systems will lead to 1 million solar roofs in California by the year 2018.
FURTHER READING
Sample solar power installation instructions
More rooftop solar panel installation instructions
Solar thermal panels for hot water heating are typically 36-75kg in weight per panel.
Solar PV panels are currently about 40-60 pounds (20-30kg).
US energy use by source
March 09, 2008
Variable sized quantum dots could lead to more efficient and partially transparent solar cells
Electron transport through a structure of nanoparticles (left) and more ordered nanotubes (center) is shown. At right, different wavelengths of light can be absorbed by different-sized quantum dots layered in a “rainbow” solar cell. Image credit: Kongkanand, et al. ©2008 ACS.
Solar cells made of different-sized quantum dots, each tuned to a specific wavelength of light could be turned into 30% efficient solar energy producing colored windows In the Notre Dame study, the scientists assembled cadmium selenide (CdSe) quantum dots in a single layer on the surface of nano films and tubes made of titanium dioxide (TiO2). After absorbing light, the quantum dots inject electrons into the TiO2 structures, which are then collected at a conducting electrode that generates photocurrent.
“Anchoring CdSe quantum dots on TiO2 nanotubes allowed us to create an ordered assembly of nanostructures,” Kamat told PhysOrg.com. “This architecture facilitated efficient transport of electrons to the collecting electrode surface and allowed us to achieve efficiency improvement.”
The researchers used four different sizes of quantum dots (between 2.3 and 3.7 nm in diameter) which exhibited absorbent peaks at different wavelengths (between 505 and 580 nm). The group observed a trade-off in performance corresponding with quantum dot size: smaller quantum dots could convert photons to electrons at a faster rate than larger quantum dots, but larger quantum dots absorbed a greater percentage of incoming photons than smaller dots. The 3-nm quantum dots offered the best compromise, but the researchers plan to improve both the conversion and absorption performances in future prototypes.
Besides investigating the quantum dots’ size quantization effect, the researchers also experimented with two different nano architectures – particle films and nanotubes – that act as scaffolds for transporting electrons from the quantum dots to the electrodes. The group found that the hollow 8000-nm-long nanotubes, where both the inner and outer surfaces were accessible to quantum dots, could transport electrons more efficiently than films.
“Usually, silicon-based photovoltaic panels operate with an efficiency of 15-20%,” Kamat said. “Silicon solar cells generate only one electron-hole pair per incident photons, irrespective of their energy. Thus, the higher energy of blue light is simply wasted in terms of heat. The obvious question is, can nanotechnology provide new ways to harvest these higher energy photons more efficiently?
“Semiconductor quantum dots seem to be the answer. They are capable of producing multiple charge carriers when excited with high energy light. If we succeed in capturing these charge carriers, we can expect significantly higher efficiencies. The target is to reach efficiency values greater than 30% using quantum dot rainbow solar cells.”
To achieve this efficiency, Kamat explained that there are two main challenges. The first is organizing the light harvesting nanostructures so that they efficiently absorb light in the visible and near infrared region, and transport electrons within the films. Secondly, the quantum dots should generate multiple charge carriers to be captured to generate photocurrent.
February 26, 2008
the Moving target for energy dominance
Members of the [NAE Engineering Grand Challenges] panel are "confident that we are not that far away from a tipping point where energy from solar will be [economically] competitive with fossil fuels," Kurzweil said, adding that it could happen within five years.
"We also see an exponential progression in the use of solar energy," he said. "It is doubling now every two years. Doubling every two years means multiplying by 1,000 in 20 years. At that rate we'll meet 100 percent of our energy needs in 20 years."
I reviewed the 14 21st century engineering grand challenges and MIT's ten emerging technologies for 2008
The National Academy of Engineering has a page that discusses the challenges for economical solar power.
The US DOE has an analysis of projected energy costs until 2030 The chart shown does not have the adjustment for operating load factors. It takes three times as much wind MW to generate the same as 1 MW of nuclear power.
The total fuel costs of a nuclear power plant in the OECD are typically about a third of those for a coal-fired plant and between a quarter and a fifth of those for a gas combined-cycle plant.
In January 2007, the approx. US $ cost to get 1 kg of uranium as UO2 reactor fuel at likely contract prices (about one third of current spot price):
Uranium: 8.9 kg U3O8 x $53 472
Conversion: 7.5 kg U x $12 90
Enrichment: 7.3 SWU x $135 985
Fuel fabrication: per kg 240
Total, approx: US$ 1787
At 45,000 MWd/t burn-up this gives 360,000 kWh electrical per kg, hence fuel cost: 0.50 c/kWh.
If assuming a higher uranium price, say two thirds of current spot price: 8.9 kg x 108 = 961, giving a total of $2286, or 0.635 c/kWh.
Fuel costs are one area of steadily increasing efficiency and cost reduction. For instance, in Spain nuclear electricity cost was reduced by 29% over 1995-2001. This involved boosting enrichment levels and burn-up to achieve 40% fuel cost reduction. Prospectively, a further 8% increase in burn-up will give another 5% reduction in fuel cost.
50 GWd/t standard burn up could go up to 65 GWd/t while still 5% enrichment Up to 100GWd/t burnup could be reached with existing reactors but would need 8-10% enrichment.
Accelerator enhanced constant reprocessing would enable Ultra high burnup of 700 GWd/t. [pg 96-102 discusses Possible Transmutation Strategies Based on Pebble Bed ADS (accelerator driven systems) Reactors for a Nuclear Fuel Cycle without Pu Recycling in Critical Reactors.]
There are many advanced fission reactor designs that are in development There are several possibilities for reducing the DOE estimated overnight construction cost in half and for reducing fueling and operating costs by four times by 2015-2020. It will take several completions of any new power plants and a few years of operations before cost reductions are recognized. China has ordered four AP1000 plants for $5.3 billion. However, until several are completed the new cost savings will not be recognized. Utilities are also continuing to order other plants which may be more expensive because Westinghouse is only able to build at a certain maximum rate.
South Africa's Pebble Bed Modular Reactor (PBMR) aims for a step change in safety, economics and proliferation resistance. Production units will be 165 MWe. They will have a direct-cycle gas turbine generator and thermal efficiency about 42%. Up to 450,000 fuel pebbles recycle through the reactor continuously (about six times each) until they are expended, giving an average enrichment in the fuel load of 4-5% and average burn-up of 90 GWday/t U (eventual target burn-ups are 200 GWd/t) [start two times as effiencient with fuel and then four times]. This means on-line refuelling as expended pebbles are replaced, giving high capacity factor.
Overnight construction cost (when in clusters of eight units) is expected to be US$ 1000/kW and generating cost below 3 US cents/kWh. A demonstration plant is due to be built in 2007 for commercial operation in 2010. A design certification application to the US Nuclear Regulatory Commission is expected in 2008, with approval expected in 2012, opening up world markets.
UPDATE: More recent estimates suggest that production costs could be US$2500-3500/kW for pebble bed reactors. Inflation in the cost of steel, cement and other materials is increasing the cost of all energy production.
According to Business Report, it could cost between $9.9 billion (R67 billion) and $13.8 billion to build 24 reactor installations, which together could generate 3,960 megawatts. That's expensive power coming in at $3,500/Kw at the upper end of the cost estimate.
A larger US design, the Modular Helium Reactor (MHR , formerly the GT-MHR), will be built as modules of up to 600 MWt. In its electrical application each would directly drive a gas turbine at 47% thermal efficiency, giving 280 MWe. It can also be used for hydrogen production (100,000 t/yr claimed) and other high temperature process heat applications. Half the core is replaced every 18 months. Burn-up is up to 220 GWd/t, and coolant outlet temperature is 850°C with a target of 1000°C.
The Westinghouse AP-1000 has received several design certifications. Overnight capital costs are projected at $1200 per kilowatt and modular design will reduce construction time to 36 months. The 1100 MWe AP-1000 generating costs are expected to be below US$ 3.5 cents/kWh and its has a 60 year operating life.
Another US-origin but international project which is a few years behind the AP-1000 is the International Reactor Innovative & Secure (IRIS). IRIS is a modular 335 MWe pressurised water reactor with integral steam generators and primary coolant system all within the pressure vessel. It is nominally 335 MWe but can be less, eg 100 MWe. Fuel is initially similar to present LWRs with 5% enrichment and burn-up of 60,000 MWd/t with fuelling interval of 3 to 3.5 years, but is designed ultimately for 10% enrichment and 80 GWd/t burn-up with an 8 year cycle, or equivalent MOX core. The core has low power density. IRIS could be deployed in the next decade (2015), and US design certification is at pre-application stage. Multiple modules are expected to cost US$ 1000-1200 per kW for power generation. They expect that construction of the first IRIS unit will be completed in three years, with subsequent reduction to only two years.
The Remote-Site Modular Helium Reactor (RS-MHR) of 10-25 MWe has been proposed by General Atomics. The fuel would be 20% enriched and refuelling interval would be 6-8 years.
Another full-size HTR design is Areva's Very High Temperature Reactor (VHTR) being put forward by Areva NP. It is based on the MHR and has also involved Fuji. Reference design is 600 MW (thermal) with prismatic block fuel like the MHR. HTRs can potentially use thorium-based fuels, such as HEU or LEU with Th, U-233 with Th, and Pu with Th. Most of the experience with thorium fuels has been in HTRs. General Atomics say that the MHR has a neutron spectrum is such and the TRISO fuel so stable that the reactor can be powered fully with separated transuranic wastes (neptunium, plutonium, americium and curium) from light water reactor used fuel. The fertile actinides enable reactivity control and very high burn-up can be achieved with it - over 500 GWd/t - the Deep Burn concept and hence DB-MHR design. Over 95% of the Pu-239 and 60% of other actinides are destroyed in a single pass.
Nuclear fusion success offers the possibility of $500/kw to $20/kw of installed power. However, there is still great uncertainty of any success with nuclear fusion.
Thermoelectrics could boost the efficiency and total power generated from high heat central power such as nuclear, coal and natural gas power plants Increasing the efficiency of power plant heat conversion to 150-200% of what they are now would greatly reduce the costs of existing plants and these types of plants. The thermoelectrics have many commonalities with advanced solar power. Broad success with solar power should also mean broad success with thermoelectronics for alternative power plants. Thermoelectronics could provide an across the board boost of 30-50% in cost efficiency for nuclear, coal and natural gas by 2020.
Kitegen offers the possibility of greatly reducing the cost and increasing the total power generated by wind while reducing the materials used in construction per MW
The Uranium hydride [nuclear battery] could be mass produced at factories starting with $1400/kw prices in 2012
So there are several possibilities getting into the range of $1000/kw overnight costs for new nuclear reactors. Advanced thermoelectronics and further advances in nuclear fuel and nuclear design could provide $500/kw prices in 2020-2030 and would have far lower variable and operating costs. Nuclear fusion could push off the day of solar power price supremacy indefinitely into the future. This will not matter if we are building nuclear fission with far less waste and no air pollution, or clean aneutronic nuclear fusion or efficient wind power. Any future with clean and abundant power would be a pretty good future.
February 15, 2008
Feed in Tariffs- support for renewable power
Some call Feed in Tariffs justified to make up for unpaid externalities from other energy sources like coal and natural gas but the incremental Feed in tariff payment is support. Even Ren21 of France calls it support. Feed in tariffs are paying a subsidy for 20 years on renewable capacity that is installed. 5.3 billion Euro is an older estimate from 2001 and the amount has gone up since then with a bigger program in Spain and other places. I like wind and solar power, but I think it is wrong to say that wind and solar are not getting enough support relative to nuclear power.
Feed in Tariff's at wikipedia
Feed in tariff is an incentive structure that boosts the adoption of renewable energy through government legislation. The regional or national electricity utilities are obligated to buy renewable electricity (electricity generated from renewable sources such as solar photovoltaics, wind power, biomass, and geothermal power) at above market rates.
Feed in tariff presentation
Not just Germany but Spain and Denmark have big feed in tariff systems. Many other European countries and Canada also have feed in tariff systems (they are just smaller programs than the German one)
Estimated impact on end use electricity prices (according to european commmission)
Between 4% and 5% for Germany and Spain
Around 15% for Denmark
Back in 2001: The Netherlands (more than EUR 1.5 billion), the UK (circa EUR 1.5 billion) and Germany (circa EUR 1.8 billion) provided substantial off -budget support to electricity consumption. The Feed in tariff support has gone up since then.
European Environment Agency figures in 2004 gave indicative estimates of total energy subsidies in the EU-15 for 2001: solid fuel (coal) EUR 13.0, oil & gas EUR 8.7, nuclear EUR 2.2, renewables EUR 5.3 billion.
Ren21 in France (pro-renewables) calls Feed in Tariffs support.
The European Environment Agency estimated at least $0.8 billion in on-budget support and $6 billion in offbudget support for renewable energy in Europe in 2001. A large share of the off-budget support was due to feed-in tariffs, with purchase obligations and competitive tendering representing other forms of off-budget support
UPDATE:
Calculating the difference between the Feed in Tariff and the market price to get the level of support.
40 billion kwh X 3 cents Euro (8 cents for wind less 5 cent market price) per kwh. Euro 1.2 billion.
That is only Germany and not the Spain and Denmark subsidies. Spain and Denmark combined have about the same wind as Germany. So that would double up differential only subsidy. 2.4 billion. Still have over a dozen other European countries like France and UK but those programs are smaller.
The solar PV tax credit is about 8 to twenty times the market rate. So subtracting out that part of the subsidy is not that different.
About 2 billion kwh for solar in Germany at 30 cents per kwh or a 25 cent premium. Some figures I have seen for the solar feed in tariff are 71 cents/kwh. 400 million more including the solar part. Double that for the rest of Europe or triple to get to the world figure.
So 2.4 billion for wind (europe only) and 800 million for solar europe only for the differential above market price for $3.2 billion Europe only feed in tariff estimate. About 30 other countries have feed in tariffs for renewables. US, Canada, Japan and other countries also have subsidies.
Most utilities in the USA charge 2-32 cent/kwh added charges for wind.
Figure from the American wind energy association
Plus there is the 1.5 cent per kwh production tax credit
Wind production incentives
Also, I don't agree with the subtract carbon emissions from that total. The carbon emissions should be counted separately as an externality or subsidy for coal, oil and natural gas. Otherwise it would be an adjustment for nuclear.
Some estimates for Solar have fairly high greenhouse gas emissions although still better than coal and natural gas
The Solar PV incentives swamp the market price figure.
So solar and wind should be supported, but it is not true that they are not getting enough support. Coal and oil are the things that should be penalized and shifted away from and it will take support for every other energy source to make that happen in a timely way.
February 13, 2008
Ultimate airships from Warren Design Vision and others
Back in 1997, Mike deGyurky, a program manager at the Jet Propulsion Laboratory (JPL), had a design for a giant blimp, perhaps a mile in length. With a cargo capacity of 50,000 tons or more.
Mike and others at JPL had the skytrain concept, which were a bunch of blimp "box cars" connected together for less drag and more fuel efficiency. The largest of the box car designs was about 45,000 tons of cargo. Updated designs would be even better now because they were depending on thin film material for the skin and for thin film solar cells for power. Both of those have seen a lot of improvement and more improvement is anticipated.
JPL was and is not in the business of building airships, but was directly connected to an institution that was; The California Institute of Technology (CalTech). CalTech had been involved in Zeppelin research during the early 1930's. Theodore von Karman, a professor of aerodynamics at CalTech and a person who had participated in airship research in Germany (including the construction of the Zeppelin "Los Angeles" as part of wartime reparations to the US.) had proposed high speed dirigibles in his autobiography . This connection was first noted by deGyurky.
There were a number of design questions that arose and a number of which remained unanswered at the time. Among them, how would the system be powered? Elements of the SkyTrain could be covered with new ultra light weight solar cells to the point of being completely solar powered. A conventionally fueled backup would be necessary for staging operations. The 1994 analysis showed that this would reduce the pure solar SkyTrain cruising speed to around 43 mph. [a proposed Skycat airship design should have a speed of 97mph. The old Zeppelin's had a maximum speed of about 65 mph, There is an Aeroscraft, hybrid airship, that has a top speed of 174 miles per hour.]
1994 analysis developed the concept in a simple minded comparative analysis of three prototypical airships, each autonomously powered and controlled, able to link and unlink to sibling cars at will.
The first SkyBoxCar analyzed was a small technology demonstrator. It was sized so that 50% of its buoyant capacity was used for lifting cargo. As a demonstrator, it would fly at relatively low altitudes and would be unable to take advantage of favorable clines in wind and solar irradiance. It would cruise at 31,000 feet at a speed of 30.7 miles per hour with a cargo capacity of 4000 pounds. It would be 125 feet long and would cost $2.5 million dollars.
The second SkyBoxCar analyzed corresponded to that of a Mack truck. It was sized to carry 45,000 pounds of payload. This increase in scale produced an efficiency increase to 74% compared to the 50% of its smaller sibling. It would cruise at 31,500 feet at a speed of approximately 43.4 mph. At 244 feet long it is four fifths the length of a football field. It would cost approximately $9,485,000.
In the interest of sheer immensity, a third SkyBoxCar was modeled with a cargo capacity 45,000 metric tons. This radical increase in size produces an efficiency increase to 98% compared to the 74% of its smaller sibling. Like its sibling however it would cruise at 33,500 feet at a speed of 43.4 mph. At 2900 feet long, it would be over half a mile in length and would cost a little over 1.3 billion dollars. A SkyBoxCar of this size violates the concept of bite-sized chunks, but is of academic interest because of its lifting efficiency and flight envelope.
"With a train of 50 airships, as opposed to 50 independent airships, you could realize perhaps a 50 [-98%] percent savings in energy, and the savings go up as the speed of travel increases.
Mass produced airships could have a projected cost of 10 cents per ton-mile, compared with the 40-to-50 cents per ton-mile charged by standard air carriers.
Skycat airship. A completed ship should be flying in 2008 and production models in early 2009.
If we had cheap carbon nanotubes [prices likely falling from $200/kg to $4/kg over the next few years] that were able to provide most of the strength to the macroscale and next generation solar cells, then Skycats that were made on the scale of the giant airships would be able to travel at 300-600mph and carry over one hundred thousand tons. Something that could make sense in the 2015-2025 timeframe.
P-791, an experimental aerostatic/aerodynamic hybrid airship developed by Lockheed-Martin corporation. The first flight of the P-791 was made on 31 January 2006. The P-791 appears to be essentially identical in design to the SkyCat design
The cancelled DARPA Walrus airship (500-1000 tons of cargo) whose work continues with Skycat and P-791.
