The maximum technical potential of renewable energies in Western Countries is very important
For electrical renewable energies, for example, the maximum theoretical potential based on the areas available in adequacy with the regulations and the quality of the deposits is estimated at more than 1,500 TWh/year (i.e. 3 times more than current French electricity demand), including 130 TWh of photovoltaic production on large commercial and industrial roofing.
The mobilization of forest biomass also presents significant potential since it would be possible, by modifying silvicultural practices, to mobilize 40% more wood by 2035 for the energy production needs.
In Green Movement prospective visions, the use of biomass remains mainly oriented towards heat production, even if significant diversification uses are envisaged (heat / electricity cogeneration, gasification, biofuels).
Green gas deposits are also significant: up to 300 TWh of green gas could be theoretically produced by 2050 from a biomass source, mainly via the anaerobic digestion and gasification.
This estimate is based on fairly ambitious assumptions of crop yield and biomass mobilization, which should be considered in an approach sustainable taking into account other dimensions: food, soil life, biodiversity, storage of carbon, biomaterials. It also depends on the ways of energy recovery from biomass (in heat, fuels, electricity or gas) which depend on arbitrations on the joint evolution of systems electrical, gas and heating networks.
Before resorting to renewable energy production, waste heat recovery aims to recover part of the heat lost in industrial or heating / cooling processes to supply heat to industrial or heating networks. The industry has a fatal heat potential of 109.5 TWh, or 36% of its fuel consumption, of which 52.9 TWh are lost above 100. To this deposit is added 8.4 TWh of heat rejected at the level of Household Waste Incineration Plants, wastewater treatment plants and data centers. In addition, 16.7 TWh of fatal heat above 60 ℃ are identified near a existing heating network, i.e. more than 70% of the energy delivered in 2013 by heating networks in developed countries. This potential represents slightly more than 1.66 million housing equivalents.
Beyond these theoretical potentials including some of the constraints, it is also necessary to take has other deployment constraints (industrial deployment capacities, etc.) or mobilization of the resource (biomass), of access to the resource (geothermal), the evolution of technology costs or still the social acceptability of their deployment.
In its plans, Green Movements proposes ambitious but realistic trajectories for the development of renewable energies in developed countries, going beyond the objectives set by law. They could represent 40% of gross final energy consumption in 2035 and 70% in 2050.
These same studies also show that the mobilization of common materials (concrete, steel, copper, aluminum) necessary for an energy transition to renewables does not lead to overconsumption incompatible with annual global production, or geological reserves existing. Work is underway to analyze more precisely the consumption of raw materials, especially those considered "critical" for the energy transition. Finally, the technologies of renewable energies do not generate significant consumption of rare earths, and in most cases wh ere they are used, substitution possibilities exist.
Many avenues exist to further mitigate the residual environmental impacts, and the diversity renewable energies can adapt the installation to the environmental and social contexts of the sites implantation. For example, setting up a geothermal hot / cold production facility for needs of a heritage building of great architectural or historical value allows to enhance a RE in all discretion, and with very low impacts. Another example, for the photovoltaic sector, a device was put in place in the Tenders to favor modules with CO2 impact the most low ; which leads manufacturers to favor the least emitting manufacturing processes.