Energy 25 October 2006

False dawn of solar power

Cosmos Online
Wind and solar power are enormously appealing as planet-friendly sources of energy - but those who think we can completely rely on them in the future are dreaming.
False dawn of solar power

A 210 kW photovoltaic system in Sacramento, California Credit: SMUD

CANBERRA: As we head into another drier, hotter summer, we can expect that every scorching day, every drought-beaten farmer, every dust storm, and every bushfire will be cited as more evidence that we should abandon our reliance on fossil-fueled energy and turn to renewable sources to beat global warming.

Let’s do that. Let’s assume that the government flicks the switch to renewables. Australia’s Prime Minister, John Howard, has a penchant for changing policy to match public opinion and snatch political initiative. He is also known for starting election years with announcements of new funding for science.

Let us assume that in January he announces that his Liberal-National coalition government will invest an extra A$1 billion in wind farms and solar power generators over two years, with the first installations happening within six months, so that they kick in before the election is due in 2007 – as the next drier, hotter summer begins.

Let us assume that successor governments increase that commitment so that A$10 billion is spent on renewable energy infrastructure in the next decade. By January 2017 our hills and sea cliffs would be bristling with windmills, our housetops and car parks would glisten with photovoltaic panels, and solar-thermal mirror farms would sparkle alongside old coal-fired power stations.

Now lets swoop ahead to eastern Australia on a hot Friday evening in late January 2017, when most of us are back at work after the summer break. The climate has been warming steadily since 2007 and will continue to do so. Global greenhouse emissions have continued to rise despite efforts by Australia and some other countries to install renewable and nuclear power generation.

It is one of those stifling, humid nights when the air seems like a hot towel and a bed sheet feels like an electric blanket. The weather forecast offers no hope of relief. The Sun is now an obdurate red ball on the western horizon, too far from the huge arrays of solar generators in eastern Australia to tickle any more juice out of them. They have closed down for the night, ready to restart 12 hours later when the morning Sun rises high enough to stir their molecules into motion.

A few wind generators are lazily turning in response to sea breezes and local storms, but most are idle in the sultry air. Those that are turning are producing too little power, too intermittently, to be useful. The eastern grid managers have switched them to bypass mode, so they too have stopped contributing to the electricity supply.

Australia is playing England in a cricket final at the Sydney Olympic Stadium. It is a night match, beginning at 6 pm and finishing around 2 am, a timing shift from earlier years in response to high daytime temperatures that have become commonplace since 2013, the hottest year on record. With players struggling in 40°C-plus afternoons and spectators opting to watch from their air-conditioned homes, the shift to night matches has revived the annual tournament.

But as the solar generators sleep and the wind farms lie fallow, where will the power come from to flood the arena with light? What will power the trains to take spectators to and from the ground?

What will power the trains in all our eastern cities, the trams in Melbourne and the trolley-buses in Brisbane, to take our workers home through the sweltering dusk? What will power the system of lights and switches that keep those public transport systems functioning? What will power all the traffic lights and street lights that make our roads safe? Where will the energy come from to keep essential data systems alive – like the databases of banks and financial institutions, welfare agencies like Centrelink, and our defence and police systems? Where will the power come from to keep our airports functioning, to pump our water and sewage around, to sustain our hospitals and power our mobile phone networks? What will drive the lifts that so many people need to get to their high-rise apartments?

So many essential things rely on electricity. So do many other things we take for granted. Keeping food and drink cold in refrigerators in our homes and shops. Air-conditioning our homes and offices. Running the television studios and their broadcasting networks to transmit their signals across the continent. Running the printing presses that hum through the night to produce our newspapers, the aluminium smelters that require huge power inputs to keep their processes running non-stop, and the dairy processing factories and bakeries that work through the night to provide fresh food for the morning.

The list goes on. What is clear is that we need electricity at night. Solar generators cannot provide that while wind farms may run overnight and during the day but cannot be relied upon. And there is no technology in sight that would enable power from these renewable sources to be stored during the day and efficiently transmitted overnight to meet baseload demand.

The mundane reality is that the power required to run eastern Australia on a hot night in 2017 will come from fossil-fuelled power stations. That will still be the case even if we spend A$10 billion on renewable generation – or even A$20 billion – over the next decade.

And even though we could get some reliable power levels from renewable sources during the day, we will have to build new fossil-fuelled power stations at the same time to keep up with Australia’s growing demand for electricity. Those power stations will need to keep their fires burning 24/7 because they cannot be turned on and off quickly. So our fossil-fuel emissions will actually increase, despite the massive investment in renewable energy that the prime minister could initiate in 2007.

Which is why he won’t do that. He may announce a few hundred million dollars towards renewable energy research – perhaps skewed to assist potentially reliable sources such as geothermal energy and thermal towers – and for research into storage technologies.

But he knows that if there is A$10 billion to be spent on new greenhouse-neutral power sources in Australia over the next decade, the best bet is nuclear power.

Simon Grose is the science editor of The Canberra Times, in which this article first appeared.

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