PNNL

Abstract

Renewable electricity generation will need to be scaled in unprecedented ways to address climate change and other environmental challenges. Doing so effectively will require an understanding of resource availability. We review estimates of the global technical potential for renewable electricity, which is defined as the amount of electricity that could be produced with current technologies accounting for geographical and technical limitations, such as land suitability and conversion efficiencies. We consider utility-scale and rooftop solar photovoltaics (PV), concentrated solar power (CSP), onshore wind, offshore wind (OSW), hydropower, geothermal electricity, ocean (wave, tidal, ocean thermal energy current (OTEC), and salinity gradient energy). We find that the reported technical potential for each energy resource ranges several orders of magnitude -- across technologies and often within technologies. Overall, when including all these energy sources, the global technical potential ranges from 1.64x102 to 2.72x104 PWh/y if we consider the minimum and maximum for each resource type and assume they are additive (no competition between resources for land, resource, etc.), which is 6.6 to 1,101 time the 2021 electricity consumption of 2.47x101 PWh/y. Utility-scale solar PV, CSP, onshore wind, and OSW have a technical global potential larger than 100 PWh per year. Geothermal electricity has a technical potential larger than 10 PWh per year, and potentially larger than 100 PWh per year if enhanced geothermal systems become sustainable. Rooftop solar PV, hydropower, and OTEC have a technical potential larger than 10 PWh per year. Wave, tidal, and salinity gradient energies are estimated to have a technical potential larger than 1 PWh per year. The technical potential provides a first order indication , since other constraints, such as economics, social and environmental concerns, or mineral scarcity may limit the overall technology deployment. Few studies have estimated the economic potential of renewables, which considers market competition with other energy sources. However, authors agree that there are no economic limitations to provide more than IEA’s future electricity demand in 2050 . Even fewer studies calculated feasible potentials, which considers societal and environmental constraints, and is therefore complicated to perform on a global scale. More studies estimating feasible should be conducted to determine the global potential of all renewables.