Towards an electricity-powered world

The purpose of this review is examination of the present scenario of electricity production and investigation of whether an electricity powered world is possible, indicating which primary energy forms should be preferably utilized. Currently, most of the primary energy used by mankind, including that employed to generate electricity, comes from fossil fuels, which need to be phased out because they bring about severe damage to climate, environment, and human health and, additionally, their stock will be largely depleted during the present century. All the energy technologies poised to replace those based on fossil fuels, namely nuclear and renewables (wind, hydro, concentrated solar power, photovoltaics, biomass, geothermal, tidal, wave) essentially produce electricity, and this suggests that we will progressively shift to an electricity-based economy over the course of the 21st century. The economic, technical, ethical and social issues entangled with nuclear technologies and the unexpectedly fast expansion of renewable energies (particularly wind and solar) point to an increasingly important role of the latter in electricity generation. The present one way utility-to-customer energy system, designed over one century ago, will need substantial reshaping to enable the build up of a smart grid capable of dealing with variable renewable supply and fluctuating end-user demand by exchange of information between customer and utility. To accomplish this result, effort in research and development of storage devices and facilities on the small (e.g., batteries, capacitors) and large (e.g., pumped hydro, compressed air storage, electrolytic hydrogen) scale is needed. In the medium and long term, the expansion of electricity production will also likely lead to progressive replacement of internal combustion engines with electric motors in the automotive sector, accompanied by a shift from individual to mass transportation systems. We have still a long way out of the fossil fuel era, but this challenge can be won only if carbon-free electricity largely replaces the direct combustion of irreplaceable and climate-altering fossil fuel resources.