The Energiewende (German for 'energy turnaround') (pronounced [ʔenɐˈɡiːˌvɛndə] ) is the ongoing energy transition by Germany. The new system intends to rely heavily on renewable energy (particularly wind, photovoltaics, and hydroelectricity), energy efficiency, and energy demand management.

An energy transition (or energy system transformation) is a major structural change to energy supply and consumption in an energy system. Currently, a transition to sustainable energy is underway to limit climate change.

NRG Energy, Inc. is an American energy company, headquartered in Houston, Texas.

Tesla Energy Operations, Inc. is the sustainable energy division of Tesla, Inc.

Renewable energy (also called green energy) is energy made from renewable natural resources that are replenished on a human timescale. The most widely used renewable energy types are solar energy, wind power, bioenergy/biomass, and hydropower.

The energy policy of India is to increase the locally produced energy in India and reduce energy poverty, with more focus on developing alternative sources of energy, particularly nuclear, solar and wind energy. Net energy import dependency was 40.9% in 2021-22.

In energy economics and ecological energetics, energy return on investment (EROI), also sometimes called energy returned on energy invested (ERoEI), is the ratio of the amount of usable energy (the exergy) delivered from a particular energy resource to the amount of exergy used to obtain that energy…

Energy storage is the capture of energy produced at one time for use at a later time to reduce imbalances between energy demand and energy production. A device that stores energy is generally called an accumulator or battery.

Renewable energy in developing countries is an increasingly used alternative to fossil fuel energy, as these countries scale up their energy supplies and address energy poverty. Renewable energy technology was once seen as unaffordable for developing countries.

Geothermal energy is thermal energy extracted from the Earth's crust. It combines energy from the planet's formation and from radioactive decay.