Energy & Utilities

Green Energy Tariffs UK — Are They Worth It?

What green energy tariffs actually mean, how they work, whether they're truly renewable, and how to choose a genuinely green energy supplier.

Green energy tariffs claim to supply your home with renewable electricity (and sometimes gas). But the reality is more nuanced. Here is what green tariffs actually mean and how to choose a genuinely sustainable option.

How Green Tariffs Work

Concept Reality
Physical electricity All goes into one National Grid — you can’t choose which electrons reach your home
What suppliers do Match your usage with renewable energy certificates (REGOs)
REGO Renewable Energy Guarantee of Origin — certificate proving 1MWh of renewable generation
The impact Suppliers buy from or invest in renewable generation

Types of Green Tariff

Type What It Means Genuineness
REGO-backed Supplier buys certificates to match your usage Basic green claim
Direct PPA Supplier has Power Purchase Agreements with specific renewable generators More genuine
Own generation Supplier owns wind/solar farms Most genuine
Green gas Includes biomethane or renewable gas Look for actual green gas, not just offsets
Carbon offset Offsets emissions rather than true renewables Least genuine (greenwashing risk)

Evaluating Genuineness

Questions to Ask

Question Good Answer Red Flag
Where does the energy come from? Named wind/solar farms, direct PPAs “Various renewable sources”
Do you own any generation? Yes Just buy REGOs
What % is backed by PPAs? High (50%+) 0% — just certificates
Is gas green? Biomethane or green hydrogen “Carbon offset” only
Investment in new renewables? Yes, X MW being built No investment

Rating Scales

Rating Source Top Rated Suppliers What They Measure
Which? Eco Providers Good Energy, Ecotricity, Octopus Transparency, investment, fuel mix
Uswitch Green Accreditation Various Minimum green standards
Your own research Check supplier’s fuel mix disclosure Annual reports, websites

Best Green Energy Suppliers

Supplier Own Generation Green Gas Rating
Good Energy Yes (solar, wind) Biomethane Top
Ecotricity Yes (significant wind) “Green gas” Top
Octopus Energy Growing generation + PPAs Carbon offsets (some criticism) Good
Bulb (now Octopus) PPAs, investment Carbon offsets Good
EDF Nuclear (low carbon, not renewable) Some offsets Mixed
Ovo PPAs, tree planting Offsets Mixed
Big Six on green tariffs Mostly REGO-backed Offsets Basic

Cost Comparison

Tariff Type Cost vs Price Cap
Best green tariffs Often at or below cap
Premium green (small suppliers) Sometimes 5–15% above cap
Big supplier green tariffs Usually at cap level
Standard (non-green) At cap (SVT)

Key point: Being green does not have to cost more. Compare prices — the best green deals compete with any tariff.

Green Gas: The Challenge

Issue Detail
Gas is harder to green Most UK heating is gas-based
Biomethane Genuine green gas from organic waste — limited supply
Hydrogen Future potential, not widely available
Carbon offsets Common but less genuine
Long-term solution Heat pumps, insulation, electrification

What “Green Gas” Usually Means

Claim Typical Reality
“100% green gas” May be offset rather than biomethane
“Carbon neutral” Often includes tree planting or offset projects
“Biomethane backed” Genuine green gas certificates
“Green future” Investment in future solutions

Beyond Green Tariffs

Action Impact
Reduce energy use Biggest impact regardless of tariff
Home insulation Reduces need for any energy
Solar panels Generate your own renewable electricity
Heat pump Electric heating from renewable grid
Switch transport EV charged on green tariff
Demand shifting Use energy when grid is greenest (wind, solar)

How to Choose

Priorities Guide

Your Priority Look For
Cheapest green option Price compare, green filter
Most genuine Good Energy, Ecotricity, Octopus
Balance of price and green Octopus, Ovo
Simple switch Any major supplier’s green tariff

Checklist Before Switching

Factor Check
☐ Price vs price cap Competitive?
☐ Fuel mix What % renewables?
☐ Certificate sourcing PPAs or just REGOs?
☐ Own generation Does supplier own wind/solar?
☐ Green gas Biomethane or just offsets?
☐ Customer reviews Service quality?
☐ Investment Adding new renewable capacity?

The Bigger Picture

Action Your Impact
Sign up for green tariff Signals demand for renewables
Choose genuinely green Supports suppliers investing in generation
Reduce consumption Biggest personal impact
Advocate for change Policy changes have largest effect

Green tariffs are one part of the puzzle. Combined with efficiency measures, they help — but the grid is decarbonising regardless as the UK builds more renewable capacity.

For more on managing energy costs, see our switching energy supplier guide and energy price cap guide.