Vt. Governor: Anthony Pollina
Vt. Lieutenant Governor: Ben Mitchell
Vt. State Representative (Hartland–West Windsor): John Bartholomew
U.S. Representative (Vt.): Peter Welch
November 3, 2008
October 30, 2008
Efficiency, capacity factor, and value
To the Editor, Geelong Advertiser:
As a science editor, I share Heinz Dahl's frustration with the inaccurate use of terms in characterizing wind energy on the grid ("Winds of change", Opinion, October 30th).
But while pretending to clarify terms, Mr. Dahl only further confuses them as he evades their unique application to wind energy.
Efficiency is not the issue. It is well understood that burning coal for electricity is only around 30 per cent efficient.
It is also well known that wind turbines generate power at an average rate of around 30 per cent of their full capacity. And although it is technically incorrect to call that their "efficiency", the word nonetheless conveys the problematic nature of wind turbines.
In common use, we don't consider our car to be only 5 per cent efficient because we drive it only an hour or so each day. If we're lucky, we consider it to be 100 per cent efficient because whenever we need it, it runs.
Mr. Dahl says that wind turbines are nearly always available, which is true. Except that if the wind isn't blowing, they aren't. And if the wind is blowing, but not within an ideal range of speed (roughly 30-60 mph), the power generated is much less than the turbines' capacity. In that sense, they are much less efficient than conventional plants which when you turn them on run reliably at full throttle.
That's the difference. Unlike conventional generators, wind turbines respond only to the wind, not to actual demand on the grid.
To pretend that there is some value in that, Mr. Dahl invents a new term, "availability capacity factor", but seems only to apply the attributes of a dispatchable conventional plant to the intermittent and variable nondispatchable output of a wind plant.
He says that when wind energy facilities have a capacity factor of 30 per cent, that means that "30 per cent of the time they are generating at full capacity".
He is completely wrong. That is what a 30 per cent capacity factor means for a conventional power plant, i.e., that it is used 30 per cent of the time.
But because the output from a wind turbine varies with the wind speed, 30 per cent capacity factor for a wind plant means that its output averages 30 per cent of its capacity. In fact, it very rarely reaches full capacity and generates at or above its average rate (i.e., 30 per cent) only about 40 per cent of the time.
Which brings us to the measure that Mr. Dahl ignored: capacity value. When power is needed on the grid, can wind plants provide it? Only by chance. Their capacity value is effectively zero. The rest of the grid still has to be kept up and running.
As a science editor, I share Heinz Dahl's frustration with the inaccurate use of terms in characterizing wind energy on the grid ("Winds of change", Opinion, October 30th).
But while pretending to clarify terms, Mr. Dahl only further confuses them as he evades their unique application to wind energy.
Efficiency is not the issue. It is well understood that burning coal for electricity is only around 30 per cent efficient.
It is also well known that wind turbines generate power at an average rate of around 30 per cent of their full capacity. And although it is technically incorrect to call that their "efficiency", the word nonetheless conveys the problematic nature of wind turbines.
In common use, we don't consider our car to be only 5 per cent efficient because we drive it only an hour or so each day. If we're lucky, we consider it to be 100 per cent efficient because whenever we need it, it runs.
Mr. Dahl says that wind turbines are nearly always available, which is true. Except that if the wind isn't blowing, they aren't. And if the wind is blowing, but not within an ideal range of speed (roughly 30-60 mph), the power generated is much less than the turbines' capacity. In that sense, they are much less efficient than conventional plants which when you turn them on run reliably at full throttle.
That's the difference. Unlike conventional generators, wind turbines respond only to the wind, not to actual demand on the grid.
To pretend that there is some value in that, Mr. Dahl invents a new term, "availability capacity factor", but seems only to apply the attributes of a dispatchable conventional plant to the intermittent and variable nondispatchable output of a wind plant.
He says that when wind energy facilities have a capacity factor of 30 per cent, that means that "30 per cent of the time they are generating at full capacity".
He is completely wrong. That is what a 30 per cent capacity factor means for a conventional power plant, i.e., that it is used 30 per cent of the time.
But because the output from a wind turbine varies with the wind speed, 30 per cent capacity factor for a wind plant means that its output averages 30 per cent of its capacity. In fact, it very rarely reaches full capacity and generates at or above its average rate (i.e., 30 per cent) only about 40 per cent of the time.
Which brings us to the measure that Mr. Dahl ignored: capacity value. When power is needed on the grid, can wind plants provide it? Only by chance. Their capacity value is effectively zero. The rest of the grid still has to be kept up and running.
October 24, 2008
October 23, 2008
Eating as if the climate mattered
By Bruce Friedrich
The National Council for Science and the Environment (NCSE) held a climate-change conference, January 16 to 18 2008 in Washington DC, which focused on solutions to the problem of human-induced climate change. And the same week, in Paris, the head of the Intergovernmental Panel on Climate Change (IPCC), which is sharing the Nobel Peace Prize with Al Gore, held a press conference to discuss "the importance of lifestyle choices" in combating global warming.
Notably, all food at the NCSE conference was vegan, and there were table-top brochures with quotes from the U.N. report on the meat industry, discussed more below. And the IPCC head, Dr. Rajendra Pachauri declared, as the Agence France-Presse (AFP) sums it up, "Don't eat meat, ride a bike, and be a frugal shopper."
The New York Times, also, seems to be jumping on the anticonsumption bandwagon. First, they ran an editorial on New Year's Day stating that global warming is "the overriding environmental issue of these times" and that we Americans are "going to have to change [our] lifestyles". The next day, they ran a superb opinion piece by Professor Jared Diamond about the fact that those of us in the developed world consume 32 times as many resources as people in the developing world and 11 times as much as China. Diamond ends optimistically, stating that "whether we get there willingly or not, we shall soon have lower consumption rates, because our present rates are unsustainable." It is reasonable for all of us to review our lives and to ask where we can cut down on our consumption--because it's necessary, and because living according to our values is what people of integrity do.
In November 2007, the United Nations environmental researchers released a report that everyone who cares about the environment should review. Called Livestock's Long Shadow, this 408-page thoroughly researched scientific report indicts the consumption of chickens, pigs, and other meats-concluding that the meat industry is "one of the ... most significant contributors to the most serious environmental problems, at every scale from local to global", and that eating meat contributes to "problems of land degradation; climate change and air pollution; water shortage and water pollution; and loss of biodiversity."
The environmental problems of meat fill books, but the intuitive argument can be put more succinctly into two points:
1) A 135-pound woman will burn off at least 1,200 calories a day even if she never gets out of bed. She uses most of what she consumes simply to power her body. Similarly, it requires exponentially more resources to eat chickens, pigs, and other animals, because most of what we feed to them is required to keep them alive, and much of the rest is turned into bones and other bits we don't eat; only a fraction of those crops is turned into meat. So you have to grow all the crops required to raise the animals to cat the animals, which is vastly wasteful relative to eating the crops directly.
2) It also requires many extra stages of polluting and energy-intensive production to get chicken, pork, and other meats to the table, including feed mills, factory farms, and slaughterhouses, all of which are riot used in the production of vegetarian foods. And then there are the additional stages of gas-guzzling, pollution-spewing transportation of moving crops, feed, animals, and meat-relative to simply growing the crops and processing them into vegetarian foods.
So when the U.N. added it all up, what they found is that eating chickens, pigs, and other animals contributes to "problems of land degradation; climate change and air pollution; water shortage and water pollution; and loss of biodiversity," and that meat-eating is "one of the ... most significant contributors to the most serious environmental problems, at every scale from local to global."
And on the issue of global warming, the issue the New York Times deems critical enough to demand that we "change [our] lifestyles" and for which Al Gore and the IPCC received the Nobel Peace Prize, the United Nations' scientists conclude that eating animals causes 40 percent more global warming than all planes, cars, trucks, and other forms of transport combined, which is why the Live Earth Global Warming Survival Handbook says that "refusing meat [is] the single most effective thing you can do to reduce your carbon footprint."
There is a lot of important attention paid to population, and that's a critical issue too, but if we're consuming I I times as much as people in China and 32 times as much as people in the third world, then it's not just about population; it's also about consumption.
NCSE, IPPC, and the U.N. deserve accolades for calling on people to stop supporting the inefficient, fossil fuel intensive, and polluting meat industry. The head of the IPCC, who received the Nobel Prize with Mr. Gore and who held last week's press conference in Paris, puts his money where his mouth is: He's a vegetarian.
The NCSE's all-vegan 3,000-person conference In January, also, sends a positive signal that other environmentalists would be wise to listen to. Thus far, among the large environmental organizations, only Greenpeace ensures that all official functions are vegetarian. Other environmental groups should follow suit.
It's empowering really, when you think about it: By choosing vegetarian foods, we're making compassionate choices that are good for our bodies, and we're living our environmental values at every meal.
American Vegan 8-1, Summer 2008, pages 12-13
The National Council for Science and the Environment (NCSE) held a climate-change conference, January 16 to 18 2008 in Washington DC, which focused on solutions to the problem of human-induced climate change. And the same week, in Paris, the head of the Intergovernmental Panel on Climate Change (IPCC), which is sharing the Nobel Peace Prize with Al Gore, held a press conference to discuss "the importance of lifestyle choices" in combating global warming.
Notably, all food at the NCSE conference was vegan, and there were table-top brochures with quotes from the U.N. report on the meat industry, discussed more below. And the IPCC head, Dr. Rajendra Pachauri declared, as the Agence France-Presse (AFP) sums it up, "Don't eat meat, ride a bike, and be a frugal shopper."
The New York Times, also, seems to be jumping on the anticonsumption bandwagon. First, they ran an editorial on New Year's Day stating that global warming is "the overriding environmental issue of these times" and that we Americans are "going to have to change [our] lifestyles". The next day, they ran a superb opinion piece by Professor Jared Diamond about the fact that those of us in the developed world consume 32 times as many resources as people in the developing world and 11 times as much as China. Diamond ends optimistically, stating that "whether we get there willingly or not, we shall soon have lower consumption rates, because our present rates are unsustainable." It is reasonable for all of us to review our lives and to ask where we can cut down on our consumption--because it's necessary, and because living according to our values is what people of integrity do.
In November 2007, the United Nations environmental researchers released a report that everyone who cares about the environment should review. Called Livestock's Long Shadow, this 408-page thoroughly researched scientific report indicts the consumption of chickens, pigs, and other meats-concluding that the meat industry is "one of the ... most significant contributors to the most serious environmental problems, at every scale from local to global", and that eating meat contributes to "problems of land degradation; climate change and air pollution; water shortage and water pollution; and loss of biodiversity."
The environmental problems of meat fill books, but the intuitive argument can be put more succinctly into two points:
1) A 135-pound woman will burn off at least 1,200 calories a day even if she never gets out of bed. She uses most of what she consumes simply to power her body. Similarly, it requires exponentially more resources to eat chickens, pigs, and other animals, because most of what we feed to them is required to keep them alive, and much of the rest is turned into bones and other bits we don't eat; only a fraction of those crops is turned into meat. So you have to grow all the crops required to raise the animals to cat the animals, which is vastly wasteful relative to eating the crops directly.
2) It also requires many extra stages of polluting and energy-intensive production to get chicken, pork, and other meats to the table, including feed mills, factory farms, and slaughterhouses, all of which are riot used in the production of vegetarian foods. And then there are the additional stages of gas-guzzling, pollution-spewing transportation of moving crops, feed, animals, and meat-relative to simply growing the crops and processing them into vegetarian foods.
So when the U.N. added it all up, what they found is that eating chickens, pigs, and other animals contributes to "problems of land degradation; climate change and air pollution; water shortage and water pollution; and loss of biodiversity," and that meat-eating is "one of the ... most significant contributors to the most serious environmental problems, at every scale from local to global."
And on the issue of global warming, the issue the New York Times deems critical enough to demand that we "change [our] lifestyles" and for which Al Gore and the IPCC received the Nobel Peace Prize, the United Nations' scientists conclude that eating animals causes 40 percent more global warming than all planes, cars, trucks, and other forms of transport combined, which is why the Live Earth Global Warming Survival Handbook says that "refusing meat [is] the single most effective thing you can do to reduce your carbon footprint."
There is a lot of important attention paid to population, and that's a critical issue too, but if we're consuming I I times as much as people in China and 32 times as much as people in the third world, then it's not just about population; it's also about consumption.
NCSE, IPPC, and the U.N. deserve accolades for calling on people to stop supporting the inefficient, fossil fuel intensive, and polluting meat industry. The head of the IPCC, who received the Nobel Prize with Mr. Gore and who held last week's press conference in Paris, puts his money where his mouth is: He's a vegetarian.
The NCSE's all-vegan 3,000-person conference In January, also, sends a positive signal that other environmentalists would be wise to listen to. Thus far, among the large environmental organizations, only Greenpeace ensures that all official functions are vegetarian. Other environmental groups should follow suit.
It's empowering really, when you think about it: By choosing vegetarian foods, we're making compassionate choices that are good for our bodies, and we're living our environmental values at every meal.
American Vegan 8-1, Summer 2008, pages 12-13
October 22, 2008
October 20, 2008
Two S.D. universities claim to be 100% wind powered while getting the same electricity as everyone else
An Oct. 15 press release from Babcock & Brown states:
wind power, wind energy
The 51-megawatt (MW) Wessington Springs Wind Farm will provide clean and renewable energy to the University of South Dakota (USD) and South Dakota State University (SDSU), which become the first universities in the Midwest to be powered with 100% renewable energy.It also says:
The power produced will connect to the Western Area Power Administration (WAPA) transmission system and be purchased by Heartland through a long-term power purchase agreement.In other words, the two universities are still getting their electricity from the same grid as everyone else. They can no more claim to be wind powered than any other customer on the system.
wind power, wind energy
October 16, 2008
Oil and coal/nuclear/wind: nothing to do with each other
The debate last night between Senators Obama and McCain illustrated a common laziness in lumping all energy together, failing to differentiate their different uses. Here are the relevant excerpts:
Therefore, clean coal, nuclear, and wind have nothing to do with oil, imported or otherwise.
As for natural gas and wind, go here.
McCain: ... We have to have nuclear power. We have to stop sending $700 billion a year to countries that don't like us very much. It's wind, tide, solar, natural gas, nuclear, off-shore drilling, ...When you talk about nuclear, coal, and wind, you are talking exclusively about electrical energy. When you talk about oil, you're talking about transport and heating. Less than 3% of the electricity in the U.S. is produced from oil, and most of that is with the otherwise unusable sludge left over from gasoline refining.
Schieffer: ... Would each of you give us a number, a specific number of how much you believe we can reduce our foreign oil imports during your first term?
McCain: ... We can eliminate our dependence on foreign oil by building 45 new nuclear plants, power plants, right away. ... with nuclear power, with wind, tide, solar, natural gas, with development of flex fuel, hybrid, clean coal technology, clean coal technology is key ...
Obama: ... And I think that we should look at offshore drilling and implement it in a way that allows us to get some additional oil. But understand, we only have three to four percent of the world's oil reserves and we use 25 percent of the world's oil, which means that we can't drill our way out of the problem. That's why I've focused on putting resources into solar, wind, biodiesel, geothermal. ...
Therefore, clean coal, nuclear, and wind have nothing to do with oil, imported or otherwise.
As for natural gas and wind, go here.
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