There are competing ideas on the best technologies to rapidly decarbonise the energy system, as required to avoid dangerous climate change. Some scenarios emphasise the role of carbon capture and storage to render coal- and gas-fired power plants more climate-friendly. Others point to nuclear energy and a third group is more optimistic on renewable sources. But it’s plausible that even these more optimistic outlooks have greatly underestimated the potential of solar power. In an analysis, just published in Nature Energy, my colleagues and I ask why this has happened and how much solar could contribute to climate mitigation. As solar becomes more central to energy supplies, battery systems and storage become increasingly important. Some states like Vermont already deploy Tesla’s home battery systems to help stabilise the grid. And in Minnesota, a study suggests solar power together with battery storage is a more cost effective way to balance the grid than natural gas. Battery costs are declining even faster than those of solar power. That is a fortunate coincidence, as storage costs rather than photovoltaic costs will be the determining factor for solar investments. Another new study, also just published in Nature Energy, finds that a combination of solar, wind and battery storage can plausibly directly compete with fossil-fuel based electricity options. Of course, effective climate mitigation is not assured even if the use of solar and wind power rise. In the absence of solid measures to remove coal, gas and oil from the energy system, fossil fuels could co-exist in an infelicitous equilibrium with renewable energies for decades to come. Pricing out polluting coal through carbon taxation would complement policy designed to boost solar’s share of the global electricity mix.
Renew Economy 30th Aug 2017 read more »