Progressive Maharashtra has rushed to install wind energy plants. But, ask Nidhi Jamwal and Shikha Lakhanpal, reporting from Mumbai and Dhule, why so little electricity is actually generated. Is there another purpose to private interest in wind? Of greater note: If India must develop wind energy, should it go the way of this state?

Go to: “Fanning an Alternative”

Go to: “When the Wind Stops”

Download “Claimed and realistic carbon dioxide emissions savings and electricity generation”

Given the possible scenarios, system-wide carbon emissions offsets are likely to be miniscule throughout most of the nation’s grids. The Electric Power Research Institute in California affirmed this circumstance, agreeing that it is technically incorrect to assume that wind energy will displace fossil generated power and decrease CO2 emissions on a kWh for kWh basis. Its report concludes that in a real operating situation, because large- scale storage of electricity is not possible, any CO2 saving will be small.

Consider an analogy between the internal combustion automobile and a hypothetical windmobile. The auto has a Capacity Factor of about 25%, limited by a combination of operator choice (people generally don’t drive them 24 hours a day each day of the year) and by the need for ongoing maintenance and continual refueling. However, when it is asked to work, it will do so with a high rate of reliability—99.9% of the time. This is its Capacity Value.

Contrast this with the windmobile, which one can never be sure if it will start or not. If that wouldn’t be annoying enough, most of the time its speed lurches between extremes, often stopping without warning. And if the windmobile became popular (due to substantial federal and state financial incentives), there would soon be an array of traffic accommodations created to enable it, such as requiring a host of new traffic controls and patterns, not to mention the borrowed cars, buses, taxis, and late appointments involved in going hither and yon. This activity corresponds to the way the grid is increasingly called upon to provide special means to integrate wind’s unreliable volatility.

A 1600MW coal plant produces a reliable, steady stream of 1600MW day and night throughout the year. It is also contained within a relatively small area and can be equipped with scrubbers to eliminate most noxious emissions, such as sulfur dioxide, nitrous oxide, and mercury. Contrast this with a wind plant consisting of 2650 turbines, each rated at 2.0MW stretched out for hundreds of miles, delivering a skittering annual average of 1600MW based upon a 30% Capacity Factor—but producing no Capacity Value.

Although the annual energy contribution of the two facilities would be equivalent on paper, the wind plant could never replace the coal plant in terms of its capacity. In fact, one should ask how many such wind facilities must be built to equal the Effective Capacity of that single coal plant. Or any conventional generating plant. And then one should ask about the thermal implications, as well as the environmental consequences, of such a vast enterprise.

The essence of “green” technology is that it strives to leave no trace. Wind is not a “leave no trace” technology. The premise behind the idea of whether we should have wind installations instead of conventional generation is badly skewed. Better to ask whether we should have phlogiston instead of oxygen in the air we breathe. Wind is a supernumerary producer of electricity enabled because the slap and tickle of wind propaganda flatters the gullible, exploits the well intentioned, and nurtures the craven. It is made possible because there’s no penalty for lying in the energy marketplace.

Download “Why Wind Won’t Work”

3.9 The unpredictability of wind generation means that the system operator cannot be confident of the output of wind farms more than an hour so into the future. Because it takes longer than one hour to bring one of the large steam turbines at Huntly coal-fired power station from “hot standby” (that is stopped but warmed up and ready to start) to full load, then very often, the system operator will be forced to keep thermal and hydro plant connected to the system and running at less than full load because of the need to have generating capacity available in case the wind drops or the expected wind does not eventuate. This is inefficient and expensive. The costs fall on the consumers. …

4.0 Meeting the Demand for electrical energy

4.1 When determining the need for new generation, sufficient electrical energy must be available to meet the forecast power demand for electricity over the critical autumn-winter period in a dry hydro year when hydro-inflows are 15-20% lower than average and the power demand is at its maximum. The autumn and winters of 1998, 2001, 2006 and 2008 are typical examples. If insufficient energy is available, the lake levels will fall, prices will rise dramatically and an electricity savings campaign may be needed to minimise or avoid the risk of power cuts.

4.2 Wind farms generate electrical energy whenever the wind is blowing. If the energy is not needed at the time that it is generated, it can often be stored in hydro storage lakes. But there are important caveats to this because, as I show below, on average, the output from the wind farms in New Zealand is about 9% below annual average output during the March to August period when lake levels are most likely to be low and there is a risk of a serious shortage. The output of the wind farms is at its highest level during the spring time. This is when the snow melts and supplies additional water into the hydro lakes. As a result of the snow melt and spring rains, the prices are often very low in the late spring and early summer thus demonstrating that any extra electricity generated during this period is of less value to our power system. …

5.12 The above and Exhibit 2 demonstrate that the System Operator’s policy of assuming that there will be no output from wind farms when scheduling generation for the day, is realistic and prudent.

5.13 I am confident that, even with widely distributed windpower, it would be risky to assume that as much as 20% of the capacity would be available during system peak demand times. Assuming that 10% would be available would be less risky because it would happen less often and, if the system operator was wrong, the chances are that there would be sufficient capacity available on the system to substitute for the missing 10%. …

Download “Likely cost of electricity from Project Hayes”

‘The results indicate that the frequent claims, electrical grids could be predominantly wind-supplied, are unrealistic. The simple reason is the discrepancy between the grid load and the variations of the spatial wind field; the grid load could only be modified by measures seriously affecting industrial activities (such as the temporary power cuts in the Californian energy crisis), while the wind field follows meteorological and aerodynamic laws and cannot be altered at all. By including wind power generation in the grid control, unpredictable power surges and high infeed to a lightly loaded grid could be mitigated, but this is not in the interest of the wind farm operators.

‘These effects might be reduced by spreading the “control energy” for wind over larger areas, which would require the legal obligations in Germany (EEG) for accepting this energy at high cost to be extended to other countries. It is unlikely that a European consensus can be reached, where countries with large hydro and pumped storage facilities would provide the needed control energy because they too may have to import thermally produced energy in dry years; there is already concern in the Scandinavian system regarding the fluctuations caused by the heavy windpower infeed and the local combinedheat- and-power plants in Denmark which require much control energy and might necessitate strengthening the high voltage grid; there are intervals when the grid operator is giving away surplus energy or paying dearly to cover power deficits. Europe-wide balancing of wind power from 25 000 MW offshore generation would definitely call for expanding the high voltage system, and transmission losses would also have to be taken into account.’

Electra, No. 204, October 2002

“Balancing Fluctuating Wind Energy with Fossil-Fuel Power Stations”

11 The most important consideration for the future electricity supply has to be security of that supply. …

12 Security of supply implies firm generation capacity with a margin above the peak (winter) demand. The firm generation is supplied by baseload power stations (such as nuclear) and despatchable (controlled by the grid) power (such as coal, gas and certain renewables such as hydro-electric — including pumped-storage schemes such as Dinorwig). Neither on-shore nor off-shore wind power stations contribute significantly to the security of supply because the electricity is intermittent, unpredictable and embedded on the grid (not despatchable). Invariably peak winter demand occurs during extreme cold weather when a high pressure system settles across northern Europe and drags in cold continental air with little wind. Even with wind turbines distributed widely across the UK, under these low wind conditions, little electricity would be generated by wind turbines. …

15 In answer to your second issue, the barriers to greater deployment of wind power stations are suitable on-shore sites, supply of wind turbine components and shortage of equipment needed for off-shore construction. In addition, serious planning issues confront on-shore wind power stations. These include the visual (landscape) and other environmental impacts, military objections (radar interference) and more recently the effect from the current large wind turbines (heights in excess of 100m) of noise and its consequential health impact. …

17 I now turn in greater detail to the technological concerns with wind turbines. As a physicist, it offends my learning, experience and intelligence to attempt to produce electricity on a large scale from wind power. This is for four reasons. Firstly, because of the very low energy density of wind (the energy per volume of moving air): For comparison and in round terms, the energy density of moving water is about 1,000 times as great, that of fossil fuels (coal, oil, liquefied gas) is about 1 billion times as great and that of nuclear is about 1 million billion times as great. Thus wind turbines have to be enormous to capture a useful amount of energy. [emphasis added] Secondly, because the power of the wind is a function of the cube of the wind speed, the electrical output is very sensitive to the wind speed. Thirdly, because of the variability of the wind, wind turbines only produce electricity at about 25% to 30% of their rated output (capacity or load factor). Fourthly, because of the intermittency and unpredictability of wind, the electricity production bears no relation to the demand for electricity. In summary, wind turbines are enormous, produce a pathetically small amount of electricity, intermittently, unpredictably and not when it is most required. [emphasis added]

18 The CO2 emissions saved by wind turbines have been calculated based on the CO2 emissions from displaced plant (coal and gas-fired power stations). A consensus figure of 430 kg/MWh is currently used. However, this figure is only part of the equation needed to calculate the CO2 emissions saved. Also to be included in the equation are the CO2 emissions resulting from the manufacture and construction of the turbine (estimated by various people at the equivalent of between several months to many years of operation — the payback period); the electricity losses down the low voltage distribution line to the consumers (estimated at between 5% and 15% of the electricity generated, due to the long distance as the result of the remoteness of many turbines); and the CO2 emissions produced by conventional power stations operating very inefficiently on standby (and burning fuel) ready as backup to meet the electricity demand when the wind drops. Evidence from Denmark and Germany suggests that CO2 emissions savings from the use of wind turbines are at best small and at worst, they may actually lead to an increase in CO2 emissions. [emphasis added]

19 Although the wind is a renewable source of energy, wind turbines can only operate on the grid in conjunction with backup generation to ensure demand is met when the wind fails. For this reason, it has been claimed that wind-generated electricity cannot be classed as renewable.

20 Because of the intermittency and unpredictability of the wind and thus of the electricity generated by wind turbines, wind turbines cannot replace a significant number of conventional power stations. Thus wind turbines are being constructed as a secondary source of electricity. In essence, the consumer is paying for two sets of electricity generation; the conventional despatchable power stations, necessary to meet demand at all times and wind turbines which operate only when the wind blows and which then displace despatchable power stations.

21 Wind turbines are usually connected to the low voltage distribution grid, rather than the high voltage transmission grid to which conventional power stations are connected. Wind-generated [power] is embedded on the grid as it is not despatchable and cannot be controlled. The national Grid was designed so that electricity flows from the power stations on the efficient high voltage transmission lines and is transformed (stepped) down progressively on the distribution grid to consumers. Thus electricity flows one way and by the most efficient route. However, embedded electricity can flow the wrong way if there is not sufficient downstream demand. This can cause grid problems.

22 Electricity cannot be stored on the grid and grid voltage and frequency are maintained in tight margins to protect sensitive equipment. This is not normally a problem, the grid having operated successfully for over 60 years. This is because demand is accurately predictable and despatchable power sources of various response times are available to match the grid. However, with increasing amounts of intermittent and unpredictable embedded generation on the grid, control becomes increasingly more difficult. This can lead to grid failure and collapse as has happened recently across a large part of Europe and in Texas.

23 In answer to your sixth issue, because of the low energy density of wind and the large separation distance required between individual turbines, the area of land affected by wind power stations is proportionally greater than that of traditional power stations. For example 100m tall wind turbines of 2MW rated power need to be spaced several hundred metres apart and not close to dwellings and roads. Thus except in remote areas, about four wind turbines can be accommodated per square kilometre of land. This is not dissimilar to the figure for nuclear power stations or gas-fired power stations. For comparison purposes, and taking into account capacity (or load factors), the land area covered by a wind power station of the same energy output as a nuclear power station would be about 2000 times as great (or an area of land 20km by 25km would be covered by wind turbines to produce the same electrical output as one nuclear power station occupying an area of land 500m square). Furthermore, the wind turbines are of greater height and rotate so that their visual impact is amplified. A considerable infrastructure in terms of possibly improved roads and access tracks is required for wind turbines. In addition, the wind turbines provide few if any jobs in the district, and possibly destroy employment due to the loss of tourism-related business. …

These external costs in terms of environmental and other impacts should be compared in terms of benefits and disbenefits for each technology on a like-for-like basis … The like-for-like basis must be in terms of energy output (i.e. MWh, GWh or TWh of electricity generated per year) rather than installed capacity (MW). Thus, for example the benefits and disbenefits of a nuclear power station of 1600MW rating with a capacity factor of 90% producing 12.6TWh of electricity per year should be compared with a wind power station consisting of 2880 2MW turbines with a capacity factor of 25% also producing 12.6TWh of electricity per year. …

Dr P A W Bratby
15th May 2008

Download “Evidence to the House of Lords Economic Affairs Committee inquiry into ‘The Economics of Renewable Energy’”

Ireland (Eirgrid): hourly wind generation and total system demand

Germany: hourly production

Spain: real-time production
Spain: balance of all sources

Ontario: hourly load by generating facility

‘Reading the sections about projected CO₂ emission savings, the report appears to be a rehashing of prior work, with little (if any) new information or data provided. It is further diminished by technical errors, conflicting information, and a frequent lack of citations to independent sources supporting the aggressive recommendations, etc. This is likely due to the fact that the only non-governmental partners in this project are AWEA (American Wind Energy Association), and consultants Black & Vaetch (who proudly proclaim on their website, “We helped launch the modern wind power industry in 1975”). … The end result is a slick AWEA promotion piece. …’

Download “How DOE + AWEA = DOA”

According to the American Wind Energy Association, the installed capacity in the San Gorgonio Pass is 565 MW. The production in 2006 was 732,561,714 kWh, or 14% of capacity (from a high in 2002 of 19.5%).

Download “SCE wind energy production records”