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.

A rooftop solar power system, or rooftop PV system, is a photovoltaic (PV) system that has its electricity-generating solar panels mounted on the rooftop of a residential or commercial building or structure. The various components of such a system include photovoltaic modules, mounting systems, cables, solar inverters…

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 renewable-energy industry is the part of the energy industry focusing on new and appropriate renewable energy technologies. Investors worldwide are increasingly paying greater attention to this emerging industry.

China is the world's top electricity producer from renewable energy sources. China's renewable energy capacity is growing faster than its fossil fuels and nuclear power capacity.

An energy superpower is a country that supplies large amounts of energy resources (crude oil, natural gas, coal, etc.) to a significant number of other countries - and therefore has the potential to influence world markets for political or economic gains. Energy superpower status might be exercised, for example, by…

Renewable energy in the United Kingdom refers to energy from renewable sources used for electricity generation, heat and transport in the United Kingdom. In 2024, renewables accounted for 50.4% of UK electricity generation and 16.2% of gross final energy consumption.

Variable renewable energy (VRE) or intermittent renewable energy sources (IRES) are renewable energy sources that are not dispatchable (adjustable on demand) due to their fluctuating nature, such as wind power and solar power, as opposed to controllable renewable energy sources, such as dammed hydroelectricity or…

Renewable energy in Germany comes mainly from wind power, solar power and biomass and is a central component of the country's Energiewende. In 2025, renewable sources accounted for 23.8% of Germany's gross final energy consumption.

Renewable energy commercialization involves the deployment of three generations of renewable energy technologies dating back more than 100 years. First-generation technologies, which are already mature and economically competitive, include biomass, hydroelectricity, geothermal power and heat.