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Documents > The backup problem > “Wind-farm developments have saved virtually zero carbon dioxide emissions”

“Wind-farm developments have saved virtually
zero carbon dioxide emissions”

Cartoon by Steve Hunter (Australia)
Cartoon by Steve Hunter (Australia)

Another study, by an Australian engineer this time, shows that wind farms do not save any fossil fuels if you include backup in the equation, and the duplication of energy-producing facilities on top of that - see earlier studies under "The backup problem" in the right margin of this page.

The prominent newspaper The Australian says: "His analysis shows that despite receiving hundreds of millions of dollars from green energy schemes driven by the renewable energy target, Victoria’s wind-farm developments have saved virtually zero carbon dioxide emissions in the state. A forensic examination of publicly available power-supply data shows Victoria’s carbon-intensive brown-coal power stations do not reduce the amount of coal they burn when wind power is available to the grid."

EPAW is glad to see this truth coming out in the mainstream media at long last. It’s been two decades since wind-sceptics started pointing to the obvious, namely that the back-up of wind’s intermittency causes much more fuel to be burnt, thus probably negating the savings realised by windfarms. Yet no government bothered to investigate this essential aspect, preferring to gobble-up the sales-pitch from the wind industry (1 kWh of wind displaces 1 kWh of coal or gas), and forgetting about due diligence and other principles of democratic governance.

LogoSeptember 1, 2012
by Graham Lloyd, Environment Editor

Hopes of slashing greenhouse emissions
just blowing in the wind

ALONGSIDE the politics of the carbon tax, a floor price, a linking to Europe or whether a direct investment scheme would be better than a market-based scheme, the bottom line surely must be whether any carbon emissions actually are being saved.

The early signs are that a $23 carbon tax has displaced some marginal high-cost generation in South Australia and Queensland, but it is too soon to say whether this is a trend or coincidence.

But any gains are swamped by the findings of a two-year analysis of Victoria's wind-farm developments by mechanical engineer Hamish Cumming.

His analysis shows that despite receiving hundreds of millions of dollars from green energy schemes driven by the renewable energy target, Victoria's wind-farm developments have saved virtually zero carbon dioxide emissions in the state.

A forensic examination of publicly available power-supply data shows Victoria's carbon-intensive brown-coal power stations do not reduce the amount of coal they burn when wind power is available to the grid.

Cumming says surplus energy is wasted to make room for intermittent supplies from wind.

Cumming's findings have been confirmed by Victoria's coal-fired electricity producers and by independent energy analysts who say it is more efficient to keep a brown-coal power-station running than turn it down and then back up.

Without gas or some other form of peaking power supply the Victorian electricity system is not equipped for the vagaries of wind power.

Even in SA, which uses gas, not coal, for base-load power and makes much greater use of wind, Cumming estimates the cost of greenhouse gas abatement at $1484 a tonne.

Cumming used data published by the Australian Energy Market Operator, which tracks power sector generation every five minutes.

The results showed fossil fuel generators, in the same periods when wind turbines had been operating, fluctuated their output to match demand but did not reduce their rate of coal consumption.

In an email to Cumming, electricity generator IPR-GDF SUEZ Australia confirmed his findings.

"Given that the power stations mentioned are all 'baseload', their generation output is relatively constant 24 hours a day, 365 days a year, other than due to minor fluctuations depending on market demand and/or shutdown of generation units for maintenance or repairs," a company spokesman said.

Cumming says his investigation demonstrates how green energy theories do not always match the facts.

A two-year email exchange between Cumming and energy companies and government regulators shows how the industry would prefer to rely on models than real-world data.

In response to questions from Inquirer, the AEMO admits that wind power presents some "challenges" but says it does displace greenhouse gas emissions from coal and gas.

"When wind is blowing and generating electricity it displaces coal and gas-fire plant in the dispatch merit order," AEMO principal media adviser Melissa Baldwin says. "As a result, fossil fuel fired plant burns less coal (or gas)."

In theory, maybe.

Cumming references an AEMO presentation to the Australian Competition & Consumer Commission where the AEMO showed that for the wind farms in SA in 2009 the greenhouse gas abatement was only 3 per cent of the total capacity of the wind farms installed.

This equated to a 0.6 per cent reduction of greenhouse gases for the entire state's electrical generation from fossil fuels.

Since then Cumming says he has established that even with the continued expansion of wind farms in South Australia, the AEMO figures show the abatement has risen to only about 4 per cent of the installed capacity, or just more than 1 per cent greenhouse gas abatement.

This is the same figure that was established in the past three months in The Netherlands and presented to the Dutch parliament. The Netherlands report suggests the greenhouse gas used to build and maintain a wind farm will not be abated even across the total life of the wind farm.

Cumming says this is exactly what he has been telling the state and federal government for the past three years.

He says the greenhouse gas savings in Victoria are even less.

In a letter to Victorian Attorney-General Robert Clark, Cumming said the owners of Yallourn, Hazelwood and Loy Yang power stations had confirmed in writing that the power stations combined consume about 7762 tonnes of coal an hour.

"They have confirmed that the power stations do not change the coal feed intake 24 hours a day, seven days a week, 365 days a year. The coal consumed by these three power stations alone makes base-load power available at a rate of 6650 megawatts," Cumming wrote. "Victoria also burns coal powering an additional emergency standby of 630 megawatts, according to Sustainable Victoria documents that were presented in your Mortlake Planning Panel. Victoria's demand only exceeds 6650MW generally for less than 10 hours every 72, and rarely exceeds 7200MW.

"AEMO five-minute data shows that peaks are picked up (ones that exceed base load) by Hydro or fossil fuel generators."

Cumming has called for Victoria's wind developments to be stripped of public subsidies.

"I have now confirmed that Acciona is not abating any GHG at all, nor has it ever nor will it during the life of the project," Cumming wrote to Clark. "Can you please arrange for a full forensic carbon audit to be performed on Acciona Waubra, and when you also conclude that it is not abating GHG, make it repay the RECs (renewable energy certificates) and other subsidies it is claiming, and ensure Acciona is charged a carbon tax of approximately $15m that it owes."

Hugh Saddler, managing director of Sustainability Advice Team Pty Ltd, says brown-coal power stations in particular are designed and built to operate on a continuous load basis. "You can see that in the longer term, in term of emissions policy, you would get a better outcome from closing down one of the brown-coal power stations altogether and using some more gas for the load following," he says.

In response to Cumming's findings, David Clarke, senior manager, community relations for Acciona Energy, which operates the Waubra wind farm, said a SKM report commissioned by the Clean Energy Council found "a 100MW wind farm operating at 35 per cent capacity factor would each year on average reduce emissions by 26,700 tonnes in the National Electricity Market." And a Sustainability Victoria commissioned report in 2006 found "abatement of between 0.25 and 0.31 million tonnes per annum for the 100MW".

However, Cumming said the reports on greenhouse gas abatement did not take into account the continuation of burning coal during the time the wind farms were operational.

"The reports you refer to are theoretical abatements, not real facts. Coal was still burnt and therefore little if any GHG was really abated," he told Clarke.

"Rather than trying to convince me with reports done by or for the wind industry, or the government departments promoting the industry, I challenge you to give me actual coal consumption data in comparison to wind generation times data that supports your argument.

"The AEMO data for this clearly shows Waubra is not abating any GHG, nor has it since the first day it began operation."

The Australian | September 1, 2012


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