One practical way many churches can take a step on that journey is by choosing a genuine green energy tariff. If your church has been thinking about switching to a greener energy supplier, you might have come across both green electricity and green gas tariffs.
Here's what that means for your church
Choosing a green electricity tariff makes a real difference.
That's because the UK's electricity system is changing rapidly. Every year, more of our electricity comes from renewable and low-carbon sources like wind and solar power. That's why switching to renewable electricity helps support the transition to a low-carbon grid.
To help churches navigate what can be a confusing market, the Church of England worked with sustainability experts Turner & Townsend to develop a robust Green Tariff Definition. We assessed suppliers not only on whether they provide genuinely renewable electricity, but also on their wider environmental and ethical practices.
Only tariffs that meet our low carbon criteria and are providing genuinely renewable electricity are included as green tariff options in the Energy Footprint Tool (EFT), giving churches confidence that their choice is making a genuine difference.
Our Green Tariff definition is speaking prophetically into how the energy market should – and can – do better for people and the planet, in line with our Christian values and beliefs.
How we can help you choose a green supplier
We have developed resources to help you to choose a green tariff, one that you can be confident is truly reducing your carbon emissions and which is not operating unethically. The Great Switch for Creation is a yearly campaign designed to help parishes confidently switch to a genuine green tariff and avoid greenwashing.
You will be able to share this with members of your congregations and communities if they want advice on genuine green tariffs. You can also sign up for our monthly Environment Bulletin and get up to date news and resources delivered straight to your inbox.
How are the suppliers chosen to be on the list of green tariffs?
It is very important that when we publish the Church of England’s carbon footprint, it is an honest and accurate calculation that can stand up to international scrutiny.
So the Church of England worked with specialist consultancy firm Turner & Townsend to rigorously assess the green tariffs available on the market. Many tariffs which are advertised as ‘green’ do not meet our ambitious criteria, for example if they are not supplying actual renewable energy from traceable sources, but instead using a standard certificated approach, or buying offsets. Find a simple explanation of how the energy market allows this ‘greenwashing’ to happen.
What criteria did we use?
Turner & Townsend worked with stakeholders across the Church of England to develop a robust definition and set of criteria to assess the tariffs. Broadly falling into 2 categories:
Low carbon criteria: Is this a genuine low carbon tariff which leads to a real carbon reduction?
Ethical criteria: Is this supplier reporting their emissions, do they invest in fossil fuels or are they building more renewable energy, how ethical are they, do they support their customers?
Find full details in the Green Tariff definition deck.
Green electricity suppliers which meet the Church of England Green Tariff Definition
| Supplier | Tariff | Does this meet our low carbon tariff criteria? | Does this meet the low carbon tariff criteria AND the ethical criteria |
|---|---|---|---|
| 100Green | All | Yes | Yes |
| Ecotricity | All | Yes | Yes |
| Parish Energy (from Ecotricity) | All | Yes | Yes |
| Good Energy | All | Yes | Yes |
| Octopus | All tariffs | Yes | Yes |
| Ovo Energy | Greener Electricity | Yes | Yes |
| Smartest Energy Commercial & Industrial | Traceable Renewable Supply Natural Renewable Supply | Yes | Yes |
| So Energy | So Fixed So Green Tracker So EV So Unique | Yes | Yes |
| SSE (Business Energy) | SSE Protect SSE Choice SSE Shaping SSE Cash Out Green Journey | Yes | Yes |
| EDF | Clean Renewable Select Renewable UK Renewable | Yes | No |
| Engie UK | UK Green UK Green Plus Green Select | Yes | No |
| E.On Next (NOT E.ON) | E.On Next tariffs | Yes | No |
| Scottish Power | Specific green tariffs only | Yes | No |
(Tariffs which met the low carbon criteria for green electricity in 2025 which are no longer available: Opus Energy (no longer trading))
Why is there a list of green tariffs in the EFT?
Choosing a green electricity supplier is an important part of reducing our carbon emissions and caring for God's creation. With this in mind, the EFT allows you to choose from a list of green tariffs when you enter your electricity consumption data.
When you tell us that you are using one of the approved green electricity tariffs, the EFT will calculate a reduction in your church's carbon footprint. However, if you are on a green gas tariff, the way this is being handled in the 2025 report onwards has changed. For more details on the reasons for this please see 'Why is green gas different' below.
The energy market analysis that we commissioned showed that the way we calculated it before 2025 wasn't accurate enough. So now that we know which tariffs offer genuine low carbon electricity your EFT report will only show a carbon saving when these genuinely green tariffs are being used.
What is the impact on parishes?
The impact of this is that some parishes may have been expecting to see a reduction in their carbon footprint and are unhappy that didn't happen if their supplier is not listed in the EFT.
Parishes are also no longer able to tick a box to say, 'I am on a green tariff but it is not listed here'. This is because the EFT can only calculate a carbon reduction when an approved tariff in the list has been selected.
Why is green gas different?
As our understanding has developed, we've updated the way we talk about green gas as part of the Church of England's journey to net zero carbon.
As a Programme, our understanding of the energy market has improved, and we want to make sure the Church of England's carbon reporting is accurate and in line with international standards.
The Church of England’s Net Zero Carbon Programme has reviewed the situation with green gas tariffs and no longer considers green gas tariffs to form part of our net zero carbon future for the following reasons:
The mains gas network is not expected to decarbonise in the same way as the electricity grid
The UK government has set a “Clean Power 2030” target for electricity, aiming for it to come almost entirely from low‑carbon sources by 2030. In practice, it is more likely that the grid becomes very close to fully low carbon in the mid‑2030s, although progress to date has been strong and this could happen sooner
There is no equivalent plan to fully decarbonise the gas grid. While there are proposals to introduce small amounts of biomethane and hydrogen, these are limited in scale. Today, over 99% of the gas in the grid is fossil fuel, and even in the long term it is expected to remain largely fossil-based
This means that choosing a “green gas” tariff does not change the physical gas used in your building. Instead, these tariffs typically match your usage with small amounts of biomethane added elsewhere to the grid, or use carbon offsetting. Because there is only a very limited supply of genuinely low‑carbon gas, and no clear pathway for the gas grid to become fully low carbon, green gas tariffs cannot be relied on as a way to reach net zero carbon. For this reason, international reporting standards don’t recognise green gas tariffs as a method of reducing carbon emissions
Green gas (100% biomethane) tariffs are also more expensive
For these reasons, we recommend focusing investment on reducing energy use and improving building efficiency, which will have a much greater impact on both emissions and energy costs. Our position will be regularly reviewed to ensure it remains aligned with international reporting standards and market innovations.
In reassessing its position on green gas tariffs, the Programme has consulted the Net Zero Carbon & Building Services Committee of the Church Buildings Council.
What if my PCC still want to choose a green gas tariff?
We understand that replacing gas boilers with electric heating is often a complex project that takes time, and many churches will continue to use mains gas while they transition to net zero carbon. In order to provide information to PCCs who wish to choose green gas we will continue to assess green gas tariffs available on the market. Below is the only tariff which has met the definition.
| Supplier | Tariff | Does this meet our low carbon tariff criteria | Does this meet the low carbon tariff criteria AND the ethical criteria |
|---|---|---|---|
| 100Green (previously Green Energy UK) | EKO Energy Sparkling Fixed Sparkling SVT | Yes | Yes |
(Tariffs which met the low carbon criteria for green gas in 2025 but not for 2026: Crown Gas and Power (100% Biogas only) – not met as there is evidence of purpose-grown crops; SSE Business Energy Green Gas Plus (also used to supply Green Journey 100% Biogas) – not sufficient evidence to meet criteria at this time.)
Why didn’t the Parish Energy Green Gas tariff meet the definition?
Parish Energy offers three gas tariffs for churches, all supplied by Corona Energy:
Standard gas
Gas with carbon offsetting
Biomethane (“green gas”)
The biomethane tariff comes close to meeting the criteria, but does not fully qualify because some of the biomethane is produced using purpose-grown crops rather than organic waste materials.
The Church of England’s criteria are intentionally ambitious. The restriction on purpose-grown crops reflects wider sustainability concerns, particularly the use of agricultural land for energy production instead of food, as well as the associated environmental impacts.