a Nuclear Engineer who works for Westinghouse. The one post, "Fitting wind onto the electricity grid," has been cross posted on the American Nuclear Society's Nuclear Cafe, and The Energy Collective. Fitting includes an excellent account of the organization of the Grid, along with a discussion of the limitations of wind power, and a case study of how wind generated electricity is integrated into the Bonneville Power Administration grid. Disher points out a number of disadvantages for wind including,
1. Adding windmills decreases the grid stability, and this limits the amount of wind energy that a grid can accommodate.Desher also notes a couple of Wind advantages,
2. Adding windmills to the grid does not add electric capacity. Stating it another way, adding windmills does not replace the need for any other generator. All the generators needed without windmills are still needed with windmills.
3. The pairing of wind with hydro has no emission benefit during periods of excess water flow (the current situation at BPA).
4. If pairing wind and natural gas is used for future capacity, it will increase emissions compared with other sources, such as emission-free nuclear.
1. The pairing of wind with hydro during periods of drought can reduce the rate of hydro head loss and therefore the need for fossil power to make up for the lack of hydro.Desher uses relatively simple conceptual models. For example he ignores Mark Z. Jacobson's contention that coupling with turbines spread out over a large area would make wind generation more reliable, but Jacobson's theory does not take into account the cost of wind redundancy or of an enlarged transmission system. It seems unlikely that Jacobson's reliable wind system would cost less than nuclear generated electricity, and very likely that it would be less much reliable than nuclear power plants.
2. The pairing of wind with natural gas can reduce the fuel used by existing natural gas plants (by about 1/3), thus reducing the emission in this pairing.
Desher take into account the possibility of coupling wind systems with energy storage to enhance wind reliability, but again coupling wind and storage is likely to be more expensive than nuclear power plants, and still would not be as reliable as a system of nuclear power plants.
Although there are some advantages to adding windmills to the grid, these advantages are not generally stated to justify them. The common justification that wind power is emission free and that using more of it will have an environmental benefit is actually not true. When we look at how wind power is accommodated on a real grid such as by BPA, there is very little, if any, environmental benefit. Other grids that have less hydro require adding natural gas plants, such as those proposed for California, and are therefore not emission free.Given the further analysis I have suggested, Desher would appear to be correct in his argument that the disadvantages of wind out weight its advantages.
Windmills can save some fuel, but the main challenge of grid operation is to supply enough capacity to meet the peak load, rather than to save fuel. Windmills do not help overcome this challenge. This is independent of how many windmills are built. Doubling or tripling the number of windmills does not help if the wind is not blowing. The hope that wind-generated power will always be able to meet the peak from some far away wind farm is not reasonable because of transmission losses. The Northeast, for example, does not benefit from the abundance of hydro in the Northwest.
The reasons for having windmills on the grid are not very convincing when looking at both the advantages and the disadvantages. The reason that there are so many wind turbines in the United States and elsewhere is primarily due to environmental politics. It is a measure of the strength of the environmental lobby. It is a forced market created by politics, not by economics or real environmental needs.
Desher followed up his first wind post with a second ANS post on The economics of wind power. The substance of this post will be clear grounds to Nuclear Green readers who have reviewed my past posting on wind. Desher actually underestimates wind construction costs. For example suggesting that a completed wind turbine would cost around $1.75 million per MW. In fact West Texas Wind turbines were costing $2.5 million. The Manzana Wind Project, a 246 megawatts (MW) California wind farm proposed by PG&E was slated to cost $900 million, or $3.66 million per MW, over twice Desher's estimate. But even while he seemingly downplays wind costs, Desher makes a strong case that wind generators are astonishingly expensive. Wing facilities typically produce far less of their rated capacity than nuclear facilities do. Nuclear power plants produce over 90% of their rated capacity, while
A typical wind farm would generate electricity about 30 percent of the time, and not necessarily at times when electricity is needed.Further nuclear plants are shut down for service during periods of low electrical demand, while wind generated electricity may be virtually non-existent during periods of peak electrical demand. Because it is down so often, wind requites backup. But,
This pairing—wind and backup—has limits because of the huge rapid variability of wind that must be compensated for by the backup power source. It is estimated that this pairing can account for only 20 percent of the capacity of the grid.It is often argued that wind can be paired with hydroelectric generators or with natural gas generators. Desher points to problems with hydro-backup.
1. Too much wind on the grid may violate the Endangered Species Act. Placing too much wind on the grid is actually a concern in California, as that state is negotiating with the neighboring Bonneville Power Administration (BPA) grid for renewable energy credits to meet its self-imposed Renewable Energy Standard. In order for the BPA to help meet California’s demand for wind-generated energy, it might need to decrease the hydro generation to the point that the excess water flow over the dams causes harmful effects to migrating salmon during the spawning season due to excess dissolved nitrogen.There are further issues that Desher ignores. The need to provide river flow for navigation is important in the American Middle west and South east. Modern river management by agencies like TVA typically commits 100% of river water to competing uses, thus the generation of more hydroelectric power would interfere with other river uses.
2. Too much wind on the grid may violate agreements to provide downstream irrigation needs. During drought situations, it may not be possible to turn down the hydro generation to let wind onto the grid and still meet irrigation needs.
we have passed laws in many states (Washington and California, for example) that do not count existing hydro into the legal definition of renewable energy.Yet hydro fits every definition of clean, sustainable energy. The purpose of such laws is obvious,
The bottom line is that we have allowed laws to be passed that are harmful both to our pocketbooks and to the environment. Without the benefit of these laws, wind developers would have lost their legally mandated status and there would be no windmills on grids with ample hydro.Nor is the pairing of wind with natural gas justified from an economic standpoint.
A simplified comparison shows that the worth of the natural gas saved is less than the cost of building and operating a wind farm. The details of the cost trade off are shown at the end of this article. . . . If the price of natural gas is low, then the worth of the saved fuel does not compensate for the cost of the wind farms. If the price is high, then the use of natural gas is not competitive with other forms of power generation.In addition to direct costs,
There are some additional costs that make the comparison even worse:Desher concludes,
# Transmission losses. Since the transmission lines from a remote wind farm are likely to be longer, a wind farm may need to be larger to provide the same amount of power as the backup. For example, if we assume a 10-percent electricity loss per 100 miles, a wind farm 500 miles away needs to be double in size.
# Transmission line cost. A remote wind farm will need expensive transmission lines to deliver the electricity. For example, a proposed new 12 000-MW high voltage transmission line connecting wind sources in New England would cost $19 billion–$25 billion. Transmission line cost may not be directly born by the power provider, so these costs may be hidden from any direct cost comparisons, but ultimately they are still paid for by the consumer or taxpayer.
there appears to be no economic justification for building windmills except when low-cost alternatives are not available. This is especially true when windmills are placed on a grid with ample hydro, as there are no compensating fuel savings in that situation.So our energy salvation is not written in the wind.
There is no free lunch.
Environmentalist have a strange;y ambivalent attitude toward fossil fuels. In the 1970's Amoey Lovins foresaw a coal bridge to a soft energy future. He argued that by 2011 we would be well on our way to a coal freer energy system, and that by 2020 coal use would be a thing of the past. Yet here we are in 2011, 9 years before the Lovins proclaimed date for the end of coal use, and coal use, as well as coal CO2 emissions is greater now than it was in 1976 when the then youthful Amory Lovins told us that coal would be by 2020 a thing of the past.
To Amory Lovins' coal bridge we must now add a environmentalist Joe Romm's argument that
low cost natural gas makes 2020 CO2 emission targets so damn easy and cheap. In other words, Romm proposes a natural gas bridge to replace Amory Lovins coal bridge to no where.
If we look at future energy plans proposed by environmental groups, we almost invariably find that they include natural gas use, as a back up to renewables, certainly, but also as a bridge to a carbon free, nuclear free future. Hence we even supposedly ultra fanatic Greenpeace propose increased natural gas use until 2030.
Yet this Green enthusiasm for natural gas is not based on a rational study of the impact of natural gas production and use on the environment, or an analysis that conclusively demonstrates that natural gas will contribute to to the mitigation of Anthropogenic Global Warming. Thus it is possible to speak of the Green Natural Gas myths, myths encouraged by propaganda from the natural gas industry, but also supported by anti-nuclear Greens, that natural gas is clean, and is a low cost route to carbon/greenhouse gas mitigation.
ProPublica is an online news source that does serious investigative journalism for a variety of traditional news media outlets. ProPublica began to challenge environmental orthodoxy on the cleanness of fracking, an alternative natural gas recovery technology that has revolutionized the Natural gas industry during the last decade. ProPullica states,
The push to find clean domestic energy has zeroed the country in on one resource it has plenty of: natural gas. Vast deposits large enough to supply the country for decades have become the focus of a drilling boom stretching across 31 states. But water contamination has also been reported in more than a thousand cases where that drilling is taking place, raising questions about the primary drilling method being used to get to the gas.ProPublica reports that
Pennsylvania . . . state officials long ago determined that the methane bubbling up in Dimock's wells was the result of the disruptive drilling processes taking place adjacent to the wells. . . . Scientists have tested the molecular composition of the methane found in Dimock and determined that it came from the Devonian layer of shale, thousands of feet below the surface. In geologic geek-speak, it's called "thermogenic," meaning it is essentially the same kind of gas that the energy companies are drilling for.The methane problem is not limited to Pennsylvania and constitutes a serious threat to some ground water users,
Residents in Dimock and across the country have found thermogenic gas in their water where drilling is taking place. Many people are blaming the invasive and controversial drilling process called hydraulic fracturing, and federal authorities are studying whether that process in particular is endangering water supplies in several states. But whether it was fracking or some other part of the drilling process -- the construction of the wells, for example -- there is little debate among regulators and scientists that the contamination in Dimock is related to the drilling.
The federal government is warning residents in a small Wyoming town with extensive natural gas development not to drink their water, and to use fans and ventilation when showering or washing clothes in order to avoid the risk of an explosion.In addition to methane, the Propublica story tells us,
Environmental Protection Agency Researchers found benzene, metals, naphthalene, phenols and methane in wells and in groundwater. They also confirmed the presence of other compounds that they had tentatively identified last summer and that may be linked to drilling activities.What does this have ti di with fracking for natural gas?
EnCana, the oil and gas company that owns most of the wells near Pavillion, has agreed to contribute to the cost of supplying residents with drinking water, even though the company has not accepted responsibility for the contamination.EPA scientist investigating Pavillion water wells found,
It found low levels of hydrocarbon compounds -- various substances that make up oil -- in 89 percent of the drinking water wells it tested. Methane gas was detected in seven of the wells and was determined to have come from the gas reservoir being tapped for energy. Eleven of the wells contained low levels of the compound 2-butoxyethanol phosphate -- a compound associated with drilling processes but that is also used as a fire retardant and a plasticizer.Propublica asserts, based on its own investigation,
An investigation by ProPublica, which visited Sublette County (Wyoming) and six other contamination sites, found that water contamination in drilling areas around the country is far more prevalent than the EPA asserts. Our investigation also found that the 2004 EPA study was not as conclusive as it claimed to be. A close review shows that the body of the study contains damaging information that wasn't mentioned in the conclusion. In fact, the study foreshadowed many of the problems now being reported across the country.A 2004 EPA report found that some chemicals used in the fracjing process are
biocides and lubricants that “can cause kidney, liver, heart, blood, and brain damage through prolonged or repeated exposure." It found that as much as a third of injected fluids, benzene in particular, remains in the ground after drilling and is “likely to be transported by groundwater."Yet environmentalists hail natural gas produced by fracking as clean. ProPublica is not ignoring radium-228, another part of the fracking story. Water used in the fracking process is typically recivered and then dumped, despite the presence if toxic chemicals including radioactive Radium-228. New York's Department of Environmental Conservation,
analyzed 13 samples of wastewater brought thousands of feet to the surface from drilling and found that they contain levels of radium-226, a derivative of uranium, as high as 267 times the limit safe for discharge into the environment and thousands of times the limit safe for people to drink.In addition to radioactive radium brought to the surface by water recovered from fracking wells, radioactive radon gas travels to the surface along with natural gas, and is released into homes, by water and space heating and by cooking with gas. I concluded about the safety issues related to
radioactive radon gas, transported to North Texas homes, from Barnett Shale gas wells, almost next door, constitutes a significant ganger to the health of North Texans. Needless to say, this problem is being ignored by gas companies, the governments of Texas, and the United States. Interestingly, it is also being ignored by critics of nuclear power who complain about the radiation dangers of nuclear power, but are unconcerned about the radiation associated with natural gas. How much is radon from natural gas effecting the health of Texans? No one knows.Thus natural gas production is far from clean, and it poses radiation threats that may be far more dangerous than those posed by nuclear power. But will it save the planet from global warming? ProPublica tells us,
Advocates for natural gas routinely assert that it produces 50 percent less greenhouse gases than coal and is a significant step toward a greener energy future. But those assumptions are based on emissions from the tailpipe or smokestack and don’t account for the methane and other pollution emitted when gas is extracted and piped to power plants and other customers.But leaks of methane gas from the natural gas indistry, raises troubling questions about natural gas as a Anthropogenic Global Warming mitigation tool. ProPublica notes,
The EPA’s new analysis doubles its previous estimates for the amount of methane gas that leaks from loose pipe fittings and is vented from gas wells, drastically changing the picture of the nation’s emissions that the agency painted as recently as April. Calculations for some gas-field emissions jumped by several hundred percent. Methane levels from the hydraulic fracturing of shale gas were 9,000 times higher than previously reported.If that were not bad enough,
When all these emissions are counted, gas may be as little as 25 percent cleaner than coal, or perhaps even less.
roughly half of the 1,600 gas-fired power plants in the United States operate at the lowest end of the efficiency spectrum. And even before the EPA sharply revised its data, these plants were only 32 percent cleaner than coal, . . . Now that the EPA has doubled its emissions estimates, the advantages are slimmer still. Based on the new numbers, the median gas-powered plant in the United States is just 40 percent cleaner than coal, according to calculations ProPublica made . . . Those 800 inefficient plants offer only a 25 percent improvement.It is far from clear that Natural Gas is the panasia for global warming. Indeed it may turn out to be another energy bridge to no where if we rely on it too much.
Other scientists say the pollution gap between gas and coal could shrink even more. That’s in part because the primary pollutant from natural gas, methane, is far more potent than other greenhouse gases, and scientists are still trying to understand its effect on the climate—and because it continues to be difficult to measure exactly how much methane is being emitted.