The Importance of Energy Storage in Delivering a Sustainable Future
Australia’s dependency on fossil fuels is often criticised – why do we rely on coal and natural gas to provide 91 % of the power to our country? Shouldn’t we be like Iceland, who use fossil fuels for less than 0.2 % of their power (relying on geothermal and hydroelectric), or Denmark, who can pull 39 % of their energy from the wind? How should we move forward as our resources are depleted, and we become starved for energy?
An oft-quoted answer is solar power. We are the sunburnt country – a dry climate and convenient latitude allow us many hours of high powered sunlight, to be harnessed by everything from rooftop panels to solar farms. Which is fantastic, right up until it’s cloudy. Or night. Or winter.
Inconsistent power supplies cannot meet the demands of a consistent society. It is not acceptable for the lights to go out when it is overcast. The elevator cannot stop working after sundown. We need some method of storing this energy – and to the surprise of many this simply doesn’t exist.
The current best method of storing electricity is through hydroelectric dams. When we have excess energy, we pump water up a hill. Then, when we are low on energy, we run the water back down, spin some turbines and supplement the grid. Pumped height storage is surprisingly efficient (over 70 %), however due to the huge infrastructure requirements, and geographical locations being a long way from the city, this only works in certain circumstances.
This problem can be solved with batteries. Batteries can store this excess energy when it is available, and release it when it is not. They are unlikely to achieve the same efficiency as hydro – but they are not geographically restricted, and can be installed without huge infrastructure commitments. Powerful batteries are the keystone in the arch of electricity generation, and as the technology develops we will see the harnessed capability of renewables explode.
If Tesla is able to bring their 100 MW array to South Australia – it will inspire confidence in this new technology. Implementing this will allow the development of renewable infrastructure around South Australia with incredible increases in efficiency, and push the energy policy of the world into the future.