Global Energy Storage Demand for a 100% Renewable Electricity Supply

This study demonstrates – based on a dynamical simulation of a global, decentralized 100% renewable electricity supply scenario – that a global climate-neutral electricity supply based on the volatile energy sources photovoltaics (PV), wind energy (onshore) and concentrated solar power (CSP) is feasible at decent cost. A central ingredient of this study is a sophisticated model for the hourly electric load demand in >160 countries. To guarantee matching of load demand in each hour, the volatile primary energy sources are complemented by three electricity storage options: batteries, high-temperature thermal energy storage coupled with steam turbine, and renewable power methane (generated via the Power to Gas process) which is reconverted to electricity in gas turbines. The study determines – on a global grid with 1°x1° resolution – the required power plant and storage capacities as well as the hourly dispatch for a 100% renewable electricity supply under the constraint of minimized total system cost (LCOE). Aggregating the results on a national level results in an levelized cost of electricity (LCOE) range of 80-200 EUR/MWh (on a projected cost basis for the year 2020) in this very decentralized approach. As a global average, 142 EUR/MWh are found. Due to the restricted number of technologies considered here, this represents an upper limit for the electricity cost in a fully renewable electricity supply.