Dave Elliott: It is often said that the central problem with renewable energy is that it is intermittent and dealing with this will add substantially to the cost. But new insights from a range of recent studies suggest that this may not be the case. For example, since balancing systems allow variable energy supply and demand to be matched more efficiently and can avoid the need for expensive new generation, the UK National Infrastructure Commission’s influential new report ‘Smart Power’ says a mix of storage, smart grid demand management and supergrid interconnectors could save UK consumers up to £8bn p.a by 2030. So grid balancing can save money – not least by avoiding wasteful curtailment of surplus output but also by trading net excesses. There will clearly be costs for adding balancing systems. However, that will be offset by the resultant system-wide cost savings, and given technology development and higher carbon prices, the International Energy Agency says the scale and impact of the extra costs should fall dramatically. The German Agora Energiewende group agrees, especially given the savings from reduced use of fossil fuel that will be enabled by wider use of renewables. That goes against the more usual view that using and balancing variable renewables will add substantially to energy costs. It ties in with a recent study from the International Renewable Energy Agency suggesting that on-shore wind would be cheaper than anything else, even with full balancing costs added. It is also often claimed that renewables will need 100% fossil (and/or nuclear) backup. However, the influential Energy Research Partnership study says that, while backup will be needed, only a 12% fossil input would be required to meet occasional demand peaks in a hypothetical 100% UK renewable scenario with wind and PV solar meeting most electricity needs most of the time, assuming that the necessary balancing facilities were in place. That translates to almost the same small fossil capacity figure as had been suggested as being needed in an earlier Poyry 2050 scenario, with renewables supplying 94% of electricity The Pugwash 80% by 2050 UK renewables study came to a similar conclusion, although it suggested that the fossil residual could be reduced further using Power to Gas conversion of surpluses.
Ambient Energy 7th July 2016 read more »