Definition and scope of renewable energy

Summary

Renewable energy is energy harnessed from natural processes that are replenished faster than they are consumed. It is commonly defined by the International Energy Agency as energy derived from natural processes that renew themselves on a timescale quicker than human use. Widely recognized renewable sources include solar power, wind power, hydropower, geothermal energy, and biomass. In terms of scope, renewable energy can be used across multiple end-uses, notably for electricity generation, hot water and space heating, transportation, and rural/off-grid energy services. Renewable energy is often discussed as a way to reduce greenhouse-gas emissions and other forms of pollution compared with fossil fuels, but it is not identical to “low-carbon” or “sustainable” energy: some renewables can still be carbon-intensive (for example, certain biomass pathways), and sustainability depends on broader long-term environmental impacts beyond carbon alone.

Key Points

• 1

  Renewable energy is defined as energy from natural processes replenished faster than they are consumed.

• 2

  Main renewable sources include solar, wind, hydropower, geothermal, and biomass.

• 3

  Renewables can serve electricity, heating, transportation, and off-grid/rural energy needs.

• 4

  Renewable energy is generally lower-emissions and less polluting than fossil fuels, but the terms “renewable,” “low-carbon,” and “sustainable” are not always synonymous.