Ecotricity is a British energy company based in Stroud, Gloucestershire, specialising in selling green energy to consumers that it primarily generates from its 87.2-megawatt wind power portfolio. It is built on the principle of heavily reinvesting its profit in building more of its own green energy generation.

EDF Energy is a British integrated energy company, wholly owned by the French state-owned EDF (Électricité de France), with operations spanning electricity generation and the sale of natural gas and electricity to homes and businesses throughout the United Kingdom. It employs 11,717 people, and handles 5.22 million…

Renewable energy progress in the European Union (EU) is driven by the European Commission's 2023 revision of the Renewable Energy Directive, which raised the EU's binding renewable energy target for 2030 to at least 42.5%, up from the previous target of 32%. Effective since November 20, 2023, across all EU countries,…

A power purchase agreement (PPA), or electricity power agreement, is a long-term contract between an electricity generator and a customer, usually a utility, government or company. PPAs may last anywhere between 5 and 20 years, during which time the power purchaser buys energy at a pre-negotiated price.

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.

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.

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

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.

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.