Calculation of Renewable Electricity Storage Cost for Future

Abstract

Electricity systems in remote areas and on islands can use electricity storage to integrate renewable generation and help meet continually varying electricity demand. Electricity storage technologies vary widely in design, technological maturity and cost. There is no single best storage technology, and storage is not necessarily appropriate for all island electricity systems. The most competitive energy storage technologies had LCOS of 50-200 $/MWh. By 2030, a much wider range of technologies offered LCOS below 100 $/MWh. Looking to 2030, it is particularly striking that battery technology becomes much more competitive. The levelized costs are higher for the wind-storage case than the solar-storage case, because of the high sensitivity of the LCOS to the number of discharge cycles per year, and the suboptimal energy-to-power ratios required for the wind-storage case as defined. An important aspect about the LCOS of storage is that it will always depend on the load factor for discharging and therefore the way it is used cannot be ignored. Battery technologies followed by sensible thermal, latent thermal and supercapacitors show the greatest reduction in cost. Battery technologies show a reduction from around 100-700 $/MWh to 50-190 $/MWh in 2030 is a reduction of over 70% in the upper cost limit in the coming years. Pumped storage shows the lowest cost reduction, due to the current maturity level of the technology, followed by compressed air energy storage.