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

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

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…

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

Constellation Energy Corporation is an American energy company headquartered in Baltimore, Maryland. The company provides electric power, natural gas, and energy management services.

The energy policy of the United Kingdom refers to the United Kingdom's efforts towards reducing energy intensity, reducing energy poverty, and maintaining energy supply reliability. The United Kingdom has had success in this, though energy intensity remains high.

Open energy-system models are energy-system models that are open source. These models can also be known as open energy models or open-source energy-system models or some combination thereof.

The energy policy of the European Union focuses on ensuring energy security and affordability, integrating the energy markets of European Union member states, improving energy efficiency, expanding renewable energy and reducing greenhouse gas emissions. Climate policy has become a central part of EU energy policy,…

Octopus Energy Group Limited (formerly Octopus Energy Limited and Octopus Energy Holdings Limited), known as Octopus Energy, is a British company operating in the fields of energy generation and supply. It was founded in 2015 with the backing of Octopus Group, a British asset management company.

O.Y. Nofar Energy Ltd., commonly known as Nofar Energy (Hebrew: ע.י. נופר אנרג'י בע"מ), is an Israeli renewable energy company headquartered in Kfar Saba.