Wind power is more reliable than gas – and much cheaper, too
As Australia’s dance of the seven RET Reviews continues, it seems like a good time to revisit one of the more persistent anti-renewables myths bandied about by fossil fuel types (and most of the Abbott government): that that renewable energy is unreliable in meeting electricity demand.
As UNSW associate professor Mark Diesendorf wrote for The Conversation one-and-a-half years ago, this old myth – long since busted by a UNSW research team, among others – “is based on the incorrect assumption that baseload demand can only be supplied by baseload power stations.”
And the fact that this is simply no longer the case was reiterated at last week’s All Energy Australia conference by Garth Heron, GM Australia for Windlab Limited.
“The argument that we need this baseload power ticking over in the background is basically false,” Heron told RenewEconomy after the conference.
“We don’t have a constant demand, so this idea that we need a constant supply is a myth.”
And as for the suggestion that wind energy is too unreliable to make any kind of meaningful contribution to the National Electricity Market, that’s a myth too, says Heron.
“There are pros and cons with all types of generation; wind and solar are reliant on renewable resources, while gas and coal are reliant on fuel supply,” he said.
“Breakdowns are also something that should to be considered – and on this front, smaller distributed generators have an advantage.
“With a gas-fired power station, you have a small amount of large generators. In the case of a wind farm, you have a large number of small generators.
“With wind, it is very unlikely you will have a simultaneous breakdown of multiple generators, whereas for a gas plant, it only takes one generator to go down and you can lose half your output.”
“In the Australia’s National Electricity Market, the network is designed such that any generator at any time can be dropped off the network and the system will continue to function within acceptable limits,” Heron elaborated in an email to RenewEconomy this week.
“This means that there is always ‘back-up’ generation standing by, waiting to respond to a network event.
“Sudden loss in wind, which in the extreme case happens over a number of minutes is a much less severe event than, for instance, having the main connection for a large power station suddenly trip.”
As if to illustrate his point, in the UK this week a major fire at RWE’s Didcot gas power station in south London on Sunday evening led to the instantaneous loss of 700MW of electricity – the equivalent of losing about half-a-million-homes-worth of power, with zero warning.
As The Guardian’s Damian Carrington has noted, this kind of major energy supply disruption happens more often than we might think.
“The Didcot fire is at least the third at a UK fossil fuel-fired power station in 2014,” he writes. “In February, fire permanently closed E.ON’s 370MW unit at Ironbridge, while in July, two units at SSE’s 1,000MW Ferrybridge coal plant in West Yorkshire were shut after a fire.”
And neither is nuclear immune from shutdowns, adds Carrington, with EDF Energy taking four of its reactors offline in August after a crack was found in a boiler.
The UK grid’s answer to these recent notable outages – together they removed a total of 7 per cent of generation capacity – was to use its regulating reserve, a mix of electricity, including pumped storage and gas power, kept in reserve to compensate for any sudden drop outs.
(Indeed, even nuclear requires a huge amount of back-up. The National Grid said that the new standby generation required to support the 3.2GW Hinckley C power generator would cost £160 million a year. That is $12 billion at current prices over the life of the plant, which is already going to cost more than $45 billion.)
The lesson, here, says Carrington, is not only that traditional fossil generation is intermittent – and dangerously so – but that “the intermittency of some renewables is simply not a problem.
“The same day the Didcot station crashed offline, wind power provided its greatest ever share of UK electricity: 24 per cent. And the lights stayed on.”
Australia experienced a similar problem in January, when a unit of the Loy Yang A brown coal generator, and the Torrens gas fired generator in South Australia, tripped on the same day. Fortunately, there was enough wind and solar generation to minimise the problems and to reduce the surge in peak pricing (much to the chagrin of coal generators who usually make much of their profits from this sort of thing).
According to Heron, big advances in wind mapping and forecasting technology like that developed by Windlab mean that the Australian Energy Market Operator is now moving towards predicting wind and predicting wind output for semi-scheduled generation.
These days, he says, the projected wind output in two hours’ time can be delivered to a high level of accuracy, while forecasts from two days out deliver a reasonable level of accuracy.
So any sudden drop in wind generation levels can be predicted, at minimum, two hours out – offering much more warning to grid operators than, say, the sudden partial shutdown, due to fire, of a Victorian coal power plant which supplies about 20% of the state’s total power.
But the literally unpredictable outages at fossil fuel plants aren’t the only x-factor clouding the horizon of traditional centralised generation networks, says Heron.
The elephant in the room, he says, the point that’s usually missing from the fossil fuels vs renewables debate, is the idea that gas and coal and any fossil fuel have huge volatility on pricing.
“In the case of Australia’s National Electricity Market, the domestic price of gas is very important in setting electricity prices,” Heron said in an email – a factor that he expects will have a huge impact on the Queensland market, in particular.
As we wrote in RenewEconomy last year, the rising cost of gas caused by the LNG boom in central Queensland is widely expected to be the single biggest cause of a future jump in electricity costs that has been estimated at $68 a year.
AGL chief economist Paul Simshauser recently warned that, in a worst-case scenario, we could see gas prices moving from the $4-$5 a gigajoule range to potentially $10 or $11 a gigajoule – a virtual doubling in price at the wholesale level.
“We are moving into a very uncertain period with respect to gas pricing,” Heron said. “Over the next few years Queensland will move from an over-supply of gas into the domestic market to become a major gas exporter with increasing amounts of shortfall in gas supply.
“Given that gas powered generation in Queensland sets the electricity price at least 40 per cent of the time – this will have a direct impact on wholesale electricity prices.”
But increasing the amount of renewables in the mix, Heron adds, particularly in Queensland, “will help to stabilise and lower wholesale electricity prices into the future.”
To illustrate his claim, Heron cites the example of South Australia, where record-breaking wind energy outputs – including one day where wind energy supplied enough electricity to power the entire state – have been shown to smooth supply, reduce the need for energy imports and reduce wholesale power costs.
This comes as no surprise to Heron.
“The whole point of putting renewables in, is to replace fossil fuel generation,” he said. “And obviously, the more generation you put into the system, more supply, always leads to lower cost of supply.”
In the case of South Australia, the added wind capacity has actually meant less reliance on back-up generation, demonstrating that grid volatility is not really increased when more renewables are added to the mix.
Needless to say, all this seems to be lost on the wind turbine hating Abbott government, and its mainstream media supporters.
Meanwhile, Heron and co. at Windlab are working on their own solution to Queensland’s unpredictable power market – a phased development of up to 1,300MW of renewable energy generation near Hughenden, 350km west of Townsville.
Called the Kennedy Wind and Solar Farm, Windlab says the project aims to deliver large-scale clean and reliable electricity to meet the growing needs of North Queensland without relying on the Copperstring Transmission project.
“Queensland is the only Australian state in the national electricity market forecast to grow significantly over the next five years,” says the ACT-based company’s website.
“AEMO forecasts that Queensland’s electricity demand will increase by up to 25% over this period. Most of this demand will be in northern Queensland where there is already a paucity of generation. Unless addressed by the development of generation capacity in North Queensland, transmission losses will continue to escalate adding hundreds of millions of dollars to the state’s community service obligation costs. The Kennedy Wind and Solar Farm will meet most of this increased demand with cheap, clean energy, generated locally in Northern Queensland.”
Note: Original story was published on www.reneweconomy.com.au