Next step needed for powerful future
As the new year gets into gear, many hope that a raft of ideas and policies for protecting energy supplies and the environment will be on the way.
One expert says good planning could allow Australia to have it both ways.
Regardless of what powers the future, University of Queensland’s Professor John Quiggin is looking to shift the focus on to better methods of storing energy.
“There is a storage problem to overcome,” Quiggin says.
Prof Quiggin agrees with those who argue that with proper power storage infrastructure, renewable energy technologies are more than ready to meet Australia’s demand.
This is something he says is “crucially important, both to the medium-term future of the Australian economy and to the long-term future of the planet.”
Now that there are a myriad of cheap and effective energy sources – based on fossil-fuels and renewable sources – Prof Quiggin says we need to think about the other side of the coin; storage.
“Going one way, the process uses energy derived from an electricity source that is in excess supply, such as solar panels at noon, or wind turbines turning late at night during low demand. Going the other way, the stored energy is turned back into electricity. Some energy is lost along the way, and other costs must be met, but if the difference in demand is great enough, there is still a net benefit.
“The general nature of the storage problem means that the range of possible solutions is vast. The reversible process might involve chemical energy (as in batteries), heat energy (as in off-peak hot water), kinetic energy (as in flywheels) or potential energy (as in pumped hydro).
“This means that solutions could be found to a wide range of energy storage problems, depending on whether the crucial requirement is cost, speed, or energy density.
“Power stations might prioritise cost-effectiveness, for example, or speed and flexibility. Car batteries, meanwhile, need dense energy storage.
“It will take some time to adapt existing solutions to new requirements, or to develop wholly new solutions,” Quiggin said.
Because of the wide base of possible storage options, the expert says better retention of renewable energy is in many ways preferable to the idea of ‘storing’ carbon emissions after the point of combustion – a process required in Federal Government ‘clean coal’ initiatives, among others.
“The contrast with carbon capture and storage [CSS] is striking,” Quiggin says.
“A CCS technology involves three stages, each with a limited range of technological options.
“First, the carbon dioxide from fossil fuels must be captured before it escapes into the atmosphere. Even the best available technologies involve the loss of up to 30% of the energy generated through combustion.
“Second, the captured carbon dioxide must be transported to a storage site. This could be avoided by building the power station close to a suitable site, but that would probably add costs in terms of fuel transport and long-distance power transmission.
“The final and most difficult step is the storage itself. The current best approach involves pumping the carbon dioxide into an underground repository, which must be stable enough to prevent leakage over an indefinite period.
“This approach has proved too expensive except, ironically, in places where the pressurized gas is used to help recover yet more crude oil from depleted wells.
“To sum up, if investing in energy storage is like backing every horse on a race, investing in CCS is like a parlay bet), which pays off only if we can pick the winners of several races in succession.
“When you think about it like that, it’s not surprising that the smart money is on storing energy, not carbon.”