Hundred percent Renewable
Renewable energy theory
Renewable energy sources are called such because they can be replenished by natural processes within a timescale that humans find useful. This means for the goals of human systems, exhausted resources will recover in an economically calculable period.
Sustainable use of energy would therefore be logically a use of a resource that does not exceed the natural restoration capacity. Fossil resources are utilized far above this limit, so are considered 'non-renewable'.
It is important to note the difference between 'primary energy carrier' and 'secondary energy carrier'. Energy carriers are substances that can release their energy content through energy conversion processes. 'Primary energy carriers' are the energy sources that are available from nature: e.g. fossil fuels (petroleum, coal, natural gas) in their extracted state, uranium, biomass, gravity (e.g., water in dams), kinetic energy (e.g. wind), radiation (e.g. sunlight), thermal (earth crustal heat). Secondary energy carriers are produced only after conversion of primary or other secondary energy sources by humans: e.g. fuels, biofuels, electrical energy: e.g. derived fuels from petroleum cracking (petrol, diesel), ethanol (biofuel), electrical energy, thermal pumps.
Fossil energy sources regenerate over millions of years. Fossil fuels, such as mineral oil, natural gas, and coal, release their chemical energy mainly through combustion. In this process, they cause environmental pollution. Therefore, the popular interpretation of the expression 'non-renewable' has extended beyond 'exhaustive' to include 'dirty' and 'polluting'.
All renewable energy sources are freely available through natural processes. The origin of solar and wind energy is solar radiation. Photovoltaic panels and solar collectors convert the solar radiation directly into electric current or heating. Wind uses the energy of the wind, which is air that is set in motion by solar energy. Hydropower comes from gravity acting on water - water which is lifted by evaporation into clouds by solar radiation.
Tidal energy comes from the effects of the gravity of the moon. Geothermal energy is due to the heat that results from radioactive elements in the earth's mantle.
However, despite the great need for alternatives to fossil fuels, solar, wind, and geothermal plants produce only 3% of the world's electricity. Hydropower, on the other hand, contributes 16%.
Renewable heat is the thermal energy that is extracted from bioenergy, solar thermal energy or geothermal energy. A common (and permissible) synonym for electricity from renewable energy sources is green power.
Solar incident radiation brings 3.9 YJ of energy in to the Earth atmosphere each year.
Annual potential of RE:
- Solar = 3.9 x 1024 J (3.9 YJ yottajoule). This equates to an average of = 1.236 x 1017 W (0.1236 EW exawatt) constant power over the year.
- Geothermal = 1.0 x 1021 J (1.0 ZJ zettajoule) = 31.6 x 1012 W (31.6 TW terawatt).
- Gravitation (tidal) = 94 x 1018 J (94 EJ exajoule) = 2.98 x 1012 W (2.98 TW terawatt).
For comparison, the International Energy Agency IEA estimates that in 2013 the total world energy consumption was 3.89 × 1020 joules (9,301 Mtoe), equal to an average power consumption of 12.3 terawatts.
Hence, total human energy demand is of the order of 0.1% (one-thousandth) of available solar incident energy, 39% of geothermal energy, and 4.1 times available tidal energy. Note that solar energy produces wind and wave energy sources as well.
UN Economic and Social Council
United Nations Economic and Social Council. A United Nations organisation with 54 members, ECOSOC coordinates the economic, social and related work of 14 UN agencies, regional commissions, functional commissions, and specialised agencies.
Some NGOs have consultative status with the council, including Global Water Partnership, Intergovernmental Forum on Mining, Minerals, Metals and Sustainable Development, Regional Organization for the Protection of the Marine Environment, World Deserts Foundation.
The functional commissions involved with ECOSOC include: United Nations Forum on Forests, Commission on Population and Development, High-level Political Forum on Sustainable Development (replacing CSD, Commission on Sustainable Development), Commission on Science and Technology for Development (CSTD). The specialised agency United Nations Environment Programme (UNEP), like many other autonomous agencies, operates through the ECOSOC mechanism.