Switching to Renewable Energy Tariffs Explained

What a renewable energy tariff actually means

When you flick a switch, the electricity arriving at your socket comes from the shared national grid — a mix of wind, solar, nuclear, gas and other sources all flowing together. No supplier can send only wind power down the wires to your particular home. So a green tariff is not about the electrons in your kettle. It is about how your supplier buys and accounts for electricity on your behalf, and what it does with the money you pay each month.

In practice, a renewable tariff is a promise about sourcing. Your supplier agrees to buy, or to match your usage with, electricity generated from renewable sources such as wind, solar, hydro and anaerobic digestion. That promise is what you are paying for, and it is worth understanding before you sign up.

Where the green electricity comes from — and how it is certified

In the UK, suppliers prove their green claims using Renewable Energy Guarantees of Origin, usually shortened to REGOs. These are certificates issued for every megawatt hour of renewable electricity generated, and they are tracked by the energy regulator. When a supplier says a tariff is 100% renewable, it generally means enough REGOs have been purchased to cover your annual usage.

Here is the nuance that catches people out. REGOs can be bought from wind farms and solar sites that already exist, sometimes years after the electricity was generated. That keeps the paperwork green, but it does not necessarily bring a single new turbine into the world. Tariffs that genuinely add to renewable capacity tend to say so plainly — for example by funding new projects, owning generation outright, or paying a price that supports development. If additionality matters to you, ask about it directly.

The main types of green tariff

• 100% renewable electricity — matched with REGOs from wind, solar or hydro. The most common option, and usually the cheapest to offer.
• Renewable electricity plus green gas — gas is typically a blend of biomethane and carbon-offset natural gas. Offsets vary hugely in quality, so ask how they are verified.
• Investment or "green fund" tariffs — a portion of your bill goes towards building new renewable generation. Often slightly dearer, with a clearer claim to additionality.
• Community and local tariffs — smaller schemes linked to a specific project nearby. Availability depends on where you live.

Some suppliers also offer tariffs that are simply the standard grid mix with a green label attached. That is not dishonest, but it is not the same thing as driving new renewable capacity, and it is reasonable to want to know which one you are choosing.

What it costs, and whether it makes a difference

Green tariffs are no longer the premium product they once were. Many now sit at or near the price of a standard variable tariff, and some fixed green deals undercut the default rates. Prices move constantly, so compare on total annual cost rather than the headline unit rate — and check the standing charge too, because it can quietly add £100 or more a year.

Do watch for exit fees on fixed green deals, which can be £30–£60 per fuel if you leave early. If you are likely to move home or switch again soon, flexible options may suit you better.

On impact: switching one household does not change the grid overnight. But the collective effect is real. When suppliers see steady demand for certified renewable electricity, they buy more of it, and the economics of new wind and solar projects improve. Your tariff is a small vote, cast every month.

Questions to ask before you switch

• Is the electricity 100% renewable, and is that backed by REGOs?
• Does the tariff support new generation, or does it rely on existing certificates?
• What is the total annual cost, including standing charges, at my actual usage?
• Are there exit fees, and how long is the contract?
• What happens to the green credentials if the supplier changes its sourcing?
• If gas is included, is the green gas certified, and how are offsets verified?

A good supplier will answer these without hedging. If the reply is vague, that tells you something useful.

Small switches, steady change

Ethical living rarely arrives in one dramatic gesture. It builds from ordinary decisions — the tariff you choose, the appliances you run at off-peak times, the washing you dry on the line instead of in a tumble dryer. Renewable tariffs work best alongside modest reductions in how much energy you use, and both together cut your bills as well as your footprint.

There is a kindness in this too. Every household that chooses a genuinely green tariff makes it slightly easier for the next one, and for the suppliers weighing up whether to invest in new generation. Take an hour this week: dig out a recent bill, note your usage, and ask the questions above. You do not need to be perfect. You just need to know what you are buying.