Green electricity

Green electricity, also called renewable electricity, is electricity generated from renewable sources such as wind, solar, hydropower, biomass and geothermal energy, instead of fossil fuels like coal, oil and gas.

Why the source of your electricity matters

Electricity generation is one of the largest sources of global CO₂ emissions, but how much CO₂ is released per kilowatt-hour varies enormously depending on what powers the local grid. Globally, electricity generation produced an average of 445g CO₂ per kWh in 2024, a figure the International Energy Agency projects will fall to around 400g CO₂/kWh by 2027 as renewable capacity grows (IEA, Electricity 2025). Grids powered mainly by hydropower, wind, nuclear or solar sit far below that global average; grids that still lean heavily on coal or gas sit far above it. Switching to a renewable-certified electricity contract is one of the more effective ways an individual can lower their footprint, particularly where the national grid still relies on fossil fuels.

How "green electricity" contracts actually work

Electricity on a shared grid isn't physically sorted by source, so a green electricity contract doesn't mean different electrons reach your home. These contracts work through certificates that confirm a matching amount of renewable electricity was generated and fed into the grid on your behalf, over the same period you consumed power. In the EU this is called a Guarantee of Origin (REGO in the UK); in the US it's a Renewable Energy Certificate (REC). Buying electricity backed by one of these certificates creates market demand for more renewable generation, even though the power reaching your specific outlet still comes from the shared grid mix.

Not all certifications are equal

A standard Guarantee of Origin or REC only confirms renewable origin. Some certification schemes go further. Sweden's Bra Miljöval label, run by Naturskyddsföreningen, requires hydropower generators to maintain a minimum water flow and follow natural flow patterns to protect plant and animal life, requires wind turbines to be sited outside protected nature areas, and channels part of the revenue into a fund for conservation projects. In the US, Green-e Energy certification applies its own additional environmental and consumer-protection criteria on top of REC eligibility. If minimizing wider ecological impact matters to you, it's worth checking whether your country has an enhanced certification like these, not just a renewable-origin one.

What to look for

Check with your electricity supplier or grid operator whether they offer a renewable or green electricity tariff backed by Guarantees of Origin, RECs, or your country's equivalent scheme, and whether a stricter certification is available if you want to go beyond the baseline.

Curious how much switching to green electricity could reduce your footprint? Calculate your carbon footprint