It’s unlikely that fossil fuel power stations that capture and store their CO2 emissions could supply eastern Australia’s electricity more cheaply than renewable energy technologies like solar and wind power. That’s according to a study based on hour-by-hour analysis of electricity demand by Ben Elliston, Iain MacGill and Mark Diesendorf from the University of New South Wales in Sydney. Although renewables are often seen as expensive, these findings highlight that they can be competitive after accounting for the impact of burning coal and gas on our climate. “Our studies, and those conducted by other research groups around the world, find that it is possible to operate reliable national and subnational electricity systems on predominantly renewable energy generated by commercially available technologies and that these systems are affordable,” Mark told me.
Ben is a PhD student, supervised by Iain and Mark, and together the three have sought to answer key questions about renewable energy. Is it possible to supply a whole electricity grid’s needs with these technologies, or are some ‘base-load’ coal or gas power stations needed to fall back on? And if it is possible, would it be affordable?
To answer these questions, Ben designed a computer programme to simulate running an electricity supply system. His program can go through a year’s hourly data on electricity demands, wind and sunshine over the region in a fraction of a second. “Everything else follows from this, provided of course one asks the right questions,” Mark noted.
Over the last two years they have published work exploiting that programme, first showing that it’s possible to reliably supply 100% of eastern Australia’s electricity using renewable energy. Wind and solar power supplied most of the electricity, but output from these technologies varies due to changes in weather. But rather than filling gaps with fossil fuels, they showed existing hydroelectric power stations and gas turbines burning biofuels could be used to meet the grid’s reliability standard. Read the rest of this entry »