Disaster in the Gulf of Mexico may give us the will to shape the future.

Twenty-eight billion is a big number. In tonnes it is a mighty load. It is the sediment eroded globally each year from all our mountains and carried by all our rivers to all our seas. It is also the amount of carbon dioxide pumped into the atmosphere each year from burning fossil fuels. In dollar terms, it is the extra money we would need to spend each year for 10 years to build a zero-emission energy system in Australia.

To make that carbon dioxide, we dig 7 billion tonnes of coal and suck countless litres of oil and gas from the ground. In total, we already excavate more rock from the Earth than nature does. We are almost at the point where oil production will start to decline, and sucking so hard it is creating problems. According to latest estimates, more than one in every 1000 barrels produced each day is now flooding into the Gulf of Mexico from BP's Deepwater Horizon well. At current growth rates, coal will have peaked by mid-century and be largely gone by the end.

Peter Seligman's Australian Sustainable Energy - by the numbers shows how a national renewable energy system can be stabilised by integrating solar, wind and, when available, geothermal energy. Seligman shows how linking it all up with a new super grid, and adding a fraction of pumped hydroelectric storage, would secure supply.

Seligman puts the cost at about $1.40 per person per day - a fraction of our national gambling habit if built over the next 25 years. But what if we wanted to do it faster, say in 10 years? How could we do it, and what would it cost?

That is the challenge outlined in Australian Sustainable energy: Zero Carbon Australia stationary energy plan, jointly published with the research organisation Beyond Zero Emissions. This study, to be launched on July 14, shows how off-the-shelf technologies could deliver a renewable energy system at cost above business-as-usual of $26 billion a year. Another big number, but in individual terms it equates to one cup of coffee per person per day.

Both studies expose as myth the argument that we need coal, gas or nuclear to provide baseload energy.

These studies provide a big vision for Australia as a renewable energy superpower. But a big vision is precisely what is needed.

Mike Sandiford is professor of geology at the University of Melbourne and director of the Melbourne Energy Institute.

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