Blowing your money on a wind turbine
I've already blogged on the completely dreadful economics of solar power... now it's time to have a look at micro wind power, of the type favoured by David Cameron (see Guardian article)
First the basics... underpinning the physics of wind power is a 'cubic law' - the power output of a wind turbine is approximately proportional to the cube of wind speed. So double the wind speed and the power goes up by eight times (2x2x2) - halve it, and it falls to one eighth, roughly.
So the value for money of a domestic wind turbine and its cost of reducing carbon depends very sensitively on the average wind speed at the site. And this, it turns out is why domestic wind turbines a sucha rotten green-buy...
The DTI has a national wind speed database which is best accessed, with useful supporting information, from the British Wind Energy Association web site. I used this to calculated the wind speed for my own area, and it comes to 4.8 metres per second at 10m above ground.
However, the rated power of the typical wind turbine (I picked the Futurenergy 1kW system at random) is based on wind speed of 12.5 m/sec... in other words, a force 6 "strong breeze". In fact, there are very few locations that have an average wind speed this high... see wind speed map of the UK - most of the country is below 6 m/sec - and this map is for wind speed at 25 metres above ground (a domestic turbine would be 5-10).
So for typical wind speeds expect much less power than it says on the tin. The main chart is derived from the better generation (an excellent site about practical green energy) and shows the approximate cubic relationship between wind speed and power output, but based on real measurements for real micro wind turbines - I've added the manufacturer's rated power and wind speed and power for my location to it. You can see a 90% fall in performance - I get about 100 watts for every rated kilowatt. But the cost doesn't change. So if I slip on the energy-numbers anorak, I calculate that a 1kW system costing just under £2,000 fully installed, would produce electricity at 22p/kWh and save carbon emissions at a cost of €450 per tonne of CO2 - more than 40 times the cost of the EU Emissions Trading System. The economics are very poor (though not as bad as for solar PV). See all data on this spreadsheet [XLS version].
Other issues arise from attaching a moving structure to your house: the advice is 'don't'. These things need to be mounted on a pole or the noise and vibration will drive you mad, and a stiff wind might damage your house.
Aren't people just trying to make a difference?
Some will object that people just want to make a green gesture - but I think people should be told when they are doing things that are terrible value for money and encouraged to spend it well, which usually means energy saving. Otherwise, there is a risk of a breach of trust and descent into cynicism about personal action and investment in the environment.
What about large wind turbines?
Large wind turbines are much better value for money, though of course with impacts of their own. They are placed in high wind-speed sites, high above the ground, and their blades have large swept area - the power output is proportional to the square of the rotor diameter as well as cube of wind speed. This is why large wind turbines have important economies of scale and why they are leading the rise of renewables.
2 comments:
MANDATORY RENEWABLE ENERGY – THE ENERGY EVOLUTION –R11
In order to insure energy and economic independence as well as better economic growth without being blackmailed by foreign countries, our country, the United States of America’s Utilization of Energy sources must change.
"Energy drives our entire economy." We must protect it. "Let's face it, without energy the whole economy and economic society we have set up would come to a halt. So you want to have control over such an important resource that you need for your society and your economy." The American way of life is not negotiable.
Our continued dependence on fossil fuels could and will lead to catastrophic consequences.
The federal, state and local government should implement a mandatory renewable energy installation program for residential and commercial property on new construction and remodeling projects with the use of energy efficient material, mechanical systems, appliances, lighting, etc. The source of energy must by renewable energy such as Solar-Photovoltaic, Geothermal, Wind, Biofuels, Ocean-Tidal, etc. including utilizing water from lakes, rivers and oceans to circulate in cooling towers to produce air conditioning and the utilization of proper landscaping to reduce energy consumption. (Sales tax on renewable energy products should be reduced or eliminated)
The implementation of mandatory renewable energy could be done on a gradual scale over the next 10 years. At the end of the 10 year period all construction and energy use in the structures throughout the United States must be 100% powered by renewable energy. (This can be done by amending building code)
In addition, the governments must impose laws, rules and regulations whereby the utility companies must comply with a fair “NET METERING” (the buying of excess generation from the consumer at market price), including the promotion of research and production of “renewable energy technology” with various long term incentives and grants. The various foundations in existence should be used to contribute to this cause.
A mandatory time table should also be established for the automobile industry to gradually produce an automobile powered by renewable energy. The American automobile industry is surely capable of accomplishing this task. As an inducement to buy hybrid automobiles (sales tax should be reduced or eliminated on American manufactured automobiles).
This is a way to expedite our energy independence and economic growth. (This will also create a substantial amount of new jobs). It will take maximum effort and a relentless pursuit of the private, commercial and industrial government sectors commitment to renewable energy – energy generation (wind, solar, hydro, biofuels, geothermal, energy storage (fuel cells, advance batteries), energy infrastructure (management, transmission) and energy efficiency (lighting, sensors, automation, conservation) (rainwater harvesting, water conservation) (energy and natural resources conservation) in order to achieve our energy independence.
"To succeed, you have to believe in something with such a passion that it becomes a reality."
Jay Draiman, Energy Consultant
Northridge, CA. 91325
Jan. 28, 2007
P.S. I have a very deep belief in America's capabilities. Within the next 10 years we can accomplish our energy independence, if we as a nation truly set our goals to accomplish this.
I happen to believe that we can do it. In another crisis--the one in 1942--President Franklin D. Roosevelt said this country would build 60,000 [50,000] military aircraft. By 1943, production in that program had reached 125,000 aircraft annually. They did it then. We can do it now.
The American people resilience and determination to retain the way of life is unconquerable and we as a nation will succeed in this endeavor of Energy Independence.
Solar energy is the source of all energy on the earth (excepting volcanic geothermal). Wind, wave and fossil fuels all get their energy from the sun. Fossil fuels are only a battery which will eventually run out. The sooner we can exploit all forms of Solar energy (cost effectively or not against dubiously cheap FFs) the better off we will all be. If the battery runs out first, the survivors will all be living like in the 18th century again.
Every new home built should come with a solar package. A 1.5 kW per bedroom is a good rule of thumb. The formula 1.5 X's 5 hrs per day X's 30 days will produce about 225 kWh per bedroom monthly. This peak production period will offset 17 to 2
4 cents per kWh with a potential of $160 per month or about $60,000 over the 30-year mortgage period for a three-bedroom home. It is economically feasible at the current energy price and the interest portion of the loan is deductible. Why not?
Title 24 has been mandated forcing developers to build energy efficient homes. Their bull-headedness put them in that position and now they see that Title 24 works with little added cost. Solar should also be mandated and if the developer designs a home that solar is impossible to do then they should pay an equivalent mitigation fee allowing others to put solar on in place of their negligence. (Installation should be paid “performance based”)
Installation of renewable energy and its performance should be paid to the installer and manufacturer based on "performance based" (that means they are held accountable for the performance of the product - that includes the automobile industry). This will gain the trust and confidence of the end-user to proceed with such a project; it will also prove to the public that it is a viable avenue of energy conservation.
Installing renewable energy system on your home or business increases the value of the property and provides a marketing advantage.
Nations of the world should unite and join together in a cohesive effort to develop and implement MANDATORY RENEWABLE ENERGY for the sake of humankind and future generations.
Jay Draiman
Northridge, CA 91325
Email: renewableenergy2@msn.com
Energy Independence begins with Energy efficiency
Updated
MANDATORY RENEWABLE ENERGY – THE ENERGY EVOLUTION –R15
By Jay Draiman, Energy Consultant
In order to insure energy and economic independence as well as better economic growth without being blackmailed by foreign countries, our country, the United States of America’s Utilization of Energy Sources must change.
"Energy drives our entire economy.” We must protect it. "Let's face it, without energy the whole economy and economic society we have set up would come to a halt. So you want to have control over such an important resource that you need for your society and your economy." The American way of life is not negotiable.
Our continued dependence on fossil fuels could and will lead to catastrophic consequences.
The federal, state and local government should implement a mandatory renewable energy installation program for residential and commercial property on new construction and remodeling projects, replacement of appliances, motors, HVAC with the use of energy efficient materials-products, mechanical systems, appliances, lighting, insulation, retrofits etc. The source of energy must be by renewable energy such as Solar-Photovoltaic, Geothermal, Wind, Biofuels, Ocean-Tidal, Hydrogen-Fuel Cell etc. This includes the utilizing of water from lakes, rivers and oceans to circulate in cooling towers to produce air conditioning and the utilization of proper landscaping to reduce energy consumption. (Sales tax on renewable energy products and energy efficiency should be reduced or eliminated)
The implementation of mandatory renewable energy could be done on a gradual scale over the next 10 years. At the end of the 10 year period all construction and energy use in the structures throughout the United States must be 100% powered by renewable energy. (This can be done by amending building code)
In addition, the governments must impose laws, rules and regulations whereby the utility companies must comply with a fair “NET METERING” (the buying of excess generation from the consumer at market price), including the promotion of research and production of “renewable energy technology” with various long term incentives and grants. The various foundations in existence should be used to contribute to this cause.
A mandatory time table should also be established for the automobile industry to gradually produce an automobile powered by renewable energy. The American automobile industry is surely capable of accomplishing this task. As an inducement to buy hybrid automobiles (sales tax should be reduced or eliminated on American manufactured automobiles).
This is a way to expedite our energy independence and economic growth. (This will also create a substantial amount of new jobs). It will take maximum effort and a relentless pursuit of the private, commercial and industrial government sectors’ commitment to renewable energy – energy generation (wind, solar, hydro, biofuels, geothermal, energy storage (fuel cells, advance batteries), energy infrastructure (management, transmission) and energy efficiency (lighting, sensors, automation, conservation) (rainwater harvesting, water conservation) (energy and natural resources conservation) in order to achieve our energy independence.
"To succeed, you have to believe in something with such a passion that it becomes a reality."
Jay Draiman, Energy Consultant
Northridge, CA. 91325
May 31, 2007
P.S. I have a very deep belief in America's capabilities. Within the next 10 years we can accomplish our energy independence, if we as a nation truly set our goals to accomplish this.
I happen to believe that we can do it. In another crisis--the one in 1942--President Franklin D. Roosevelt said this country would build 60,000 [50,000] military aircraft. By 1943, production in that program had reached 125,000 aircraft annually. They did it then. We can do it now.
"the way we produce and use energy must fundamentally change."
The American people resilience and determination to retain the way of life is unconquerable and we as a nation will succeed in this endeavor of Energy Independence.
The Oil Companies should be required to invest a substantial percentage of their profit in renewable energy R&D and implementation. Those who do not will be panelized by the public at large by boy cutting their products.
Solar energy is the source of all energy on the earth (excepting volcanic geothermal). Wind, wave and fossil fuels all get their energy from the sun. Fossil fuels are only a battery which will eventually run out. The sooner we can exploit all forms of Solar energy (cost effectively or not against dubiously cheap FFs) the better off we will all be. If the battery runs out first, the survivors will all be living like in the 18th century again.
Every new home built should come with a solar package. A 1.5 kW per bedroom is a good rule of thumb. The formula 1.5 X's 5 hrs per day X's 30 days will produce about 225 kWh per bedroom monthly. This peak production period will offset 17 to 2
4 cents per kWh with a potential of $160 per month or about $60,000 over the 30-year mortgage period for a three-bedroom home. It is economically feasible at the current energy price and the interest portion of the loan is deductible. Why not?
Title 24 has been mandated forcing developers to build energy efficient homes. Their bull-headedness put them in that position and now they see that Title 24 works with little added cost. Solar should also be mandated and if the developer designs a home that solar is impossible to do then they should pay an equivalent mitigation fee allowing others to put solar on in place of their negligence. (Installation should be paid “performance based”).
Installation of renewable energy and its performance should be paid to the installer and manufacturer based on "performance based" (that means they are held accountable for the performance of the product - that includes the automobile industry). This will gain the trust and confidence of the end-user to proceed with such a project; it will also prove to the public that it is a viable avenue of energy conservation.
Installing a renewable energy system on your home or business increases the value of the property and provides a marketing advantage. It also decreases our trade deficit.
Nations of the world should unite and join together in a cohesive effort to develop and implement MANDATORY RENEWABLE ENERGY for the sake of humankind and future generations.
The head of the U.S. government's renewable energy lab said Monday (Feb. 5) that the federal government is doing "embarrassingly few things" to foster renewable energy, leaving leadership to the states at a time of opportunity to change the nation's energy future. "I see little happening at the federal level. Much more needs to happen." What's needed, he said, is a change of our national mind set. Instead of viewing the hurdles that still face renewable sources and setting national energy goals with those hurdles in mind, we should set ambitious national renewable energy goals and set about overcoming the hurdles to meet them. We have an opportunity, an opportunity we can take advantage of or an opportunity we can squander and let go,"
solar energy - the direct conversion of sunlight with solar cells, either into electricity or hydrogen, faces cost hurdles independent of their intrinsic efficiency. Ways must be found to lower production costs and design better conversion and storage systems.
Disenco Energy of the UK has announced it has reached important
milestones leading to full commercialization, such as the completion of
field trials for its home, micro combined heat and power plant (m-CHP).
The company expects to begin a product roll out in the second quarter of
2008.
Operating at over 90 percent efficiency, the m-CHP will be able to
provide 15 kilowatts of thermal energy (about 50,000 Btu’s) for heat and
hot water and generate 3 kilowatts of electricity. The m-CHP uses a
Stirling engine generator and would be a direct replacement for a home’s
boiler.
Running on piped-in natural gas the unit would create some independence
from the power grid, but still remain connected to the gas supply
network.
Whereas heat is supplied only when the generator is running (or
conversely electricity is generated only when heat is needed) a back-up
battery system and heavily insulated hot water storage tank seem
eventual options for more complete energy independence.
FEDERAL BUILDINGS WITH SOLAR ENERGY – Renewable Energy
All government buildings, Federal, State, County, City etc. should be mandated to be energy efficient and must use renewable energy on all new structures and structures that are been remodeled/upgraded.
"The government should serve as an example to its citizens"
Jay Draiman, Energy Consultant
Northridge, CA 91325
Email: renewableenergy2@msn.com.
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