Lowering bills, cutting carbon


Here's a selection of our most frequently asked questions and some points we thought you should know. More questions? Feel free to contact us

  • What do you mean by 'green energy'?

    We use ‘green’ energy as shorthand for power from renewable sources – sun, wind, water (river dams, tidal or wave power) and biofuels (such as gas released by rotting food or crops*). Unlike electricity generated by burning dirty fossil fuels like oil, coal and gas, green energy is renewable and has very little impact in terms of climate change and air pollution. Although nuclear power has a smaller impact than fossil fuels in terms of climate change, we know a lot of people currently have concerns about buying nuclear energy, so none of the electricity covered by the tariffs on our site includes nuclear power.
    * Although burning gas from decomposing organic matter releases carbon emissions, biofuels are considered renewable and low-carbon because the plants are replaced with new crops, which absorb an equivalent amount of carbon dioxide – one of the main gases contributing to climate change.

  • Isn't green energy expensive?

    No. Most green energy tariffs are now hundreds of pounds cheaper than the standard variable rate tariffs most households in the UK are on. That’s because the cost of generating renewable energy is getting lower and lower. Think about it – once you’ve built a wind turbine or a solar panel, nature does the rest! In fact, wind is now the cheapest form of energy in the UK and other renewables like solar aren’t far behind.

  • How can some electricity be clean? Doesn’t it all come through the same wires?

    Most UK homes are powered by electricity from the National Grid, and their electricity may be produced by any number of regional generators, using both ‘dirty’ and ‘clean’ sources. If you’re wondering how your tariff could be ‘clean’, imagine the Grid being a bit like a pond, with both dirty water and clean water flowing into it. When you sign up to a clean tariff, the supplier guarantees that they’ll put as much clean energy into the pond as the energy you take out. The more people who buy clean electricity, the more clean energy is guaranteed to go into the pond, and the cleaner the pond gets.

  • Is green energy unreliable?

    No. Most homes in the UK get their electricity from the National Grid. When you switch to a green energy supplier, they guarantee that for every unit of electricity you take out of the Grid, they’ll put the same amount of renewable energy back in, helping to clean up our power supply. Better electricity, rain or shine.

  • Can I get green gas as well as electricity?

    Traditionally, our electricity was generated by burning fossil fuels. The energy from this drove turbines, which generated the electricity. By replacing fossil fuels with energy from the sun, wind and water, we can generate green electricity without the pollution and carbon emissions.

    Gas is unfortunately much harder to replace, because we’re directly burning a fossil fuel, rather than using it to generate a different form of power. It is possible to generate gas from plant crops (including food waste). Although this is still a fossil fuel, it has lower carbon emissions, providing the crops used are replaced (because plants absorb carbon dioxide – a greenhouse gas – from the air). However, so far, this lower carbon gas still makes up a very small proportion of the gas used by UK homes – too little for suppliers to be able to offer ‘100% green gas’ in the same way as you can get 100% green electricity.

  • Fixed or variable tariff? What's the difference, and which is right for me?

    If you’ve used our site to compare the prices of different green energy tariffs, you may have noticed that they come in two types – ‘fixed’ or ‘variable’. What’s the difference?

    Fixed tariffs

    When you sign up to a fixed tariff, the amount you’re charged for a unit of energy will stay the same for a set period (usually a year). The total amount you pay could still go up or down depending on how much energy you use.

    If you leave a fixed tariff before the end of that set period, you’ll usually be charged a penalty fee, which will be added to your final bill. And when you come to the end of a fixed tariff, you’ll usually role onto the suppliers’ most expensive variable tariff, so remember to switch again before this happens.

    Variable tariffs

    When you’re on a variable rate tariff, your supplier can increase or decrease the amount they charge you for a unit of energy, providing they give you advanced warning. Unlike fixed tariffs, there’s no charge for leaving a variable tariff, so if the price does change, you’re free to go elsewhere.

    Which is right for you?

    If you want the certainty of knowing that the price of the energy you’re buying won’t change for a set period, opt for a fixed tariff. If you don’t mind uncertainty (and remember prices can go down as well as up) and would rather not have to switch at the end of every fixed term deal, then a variable rate may be better for you.

    How your quote is calculated

    When you come to the end of a fixed rate tariff, you’re likely to drop onto your supplier’s most expensive variable rate tariff. Our site will take that into account when it generates your quote. As a result, the estimate for how much you’ll pay over a year will factor in any extra cost associated with rolling onto your supplier’s variable rate.

  • Will I be charged for switching?

    Switching is free. The only way you’d be charged is if you signed up to a cheap tariff for a fixed period with your existing supplier. Their terms and conditions may allow them to charge you a penalty for leaving them before the end of that period. However, switching may still be worth your while, if the savings outweigh the penalty. If you think an early-leaving charge might apply to you, give us a ring on 0800 0370 697 and we can talk you through the options.

  • How do I find out my meter number?

    There are two types of meter number – one for gas, known as an MPR (meter point reference) and one for electricity, known as an MPAN (metering point administration number). In most cases, our system can identify these numbers by looking up your address in a national database. Occasionally, however, this information can’t be found in the database, and you’ll need to enter your meter number manually.

    If you can’t find the number on the meter itself, it should be shown on a past bill. If you don’t have a past bill, then you can get your gas MPR by telephoning Xoserve, which manages the data for the UK gas industry, on 0870 608 1524. To find out your electricity MPAN, you’ll need to telephone your local electricity distributor. You can find out who this is by visiting www.energynetworks.org.

  • Should I trust a supplier I've never heard of?

    Many green energy suppliers are actually market leaders when it comes to customer service. Octopus, Ecotricity and So Energy are all recognised for customer service in the top 10 of Which?’s annual survey of UK homes, while many of our suppliers also boast ‘excellent’ ratings on TrustPilot. It turns out being customer-focused is all part of being an ethical company. Plus, they’ve often had plenty of practice – Good Energy has been around since 2002, while Ecotricity was founded in 1996!

  • How does changing supplier work?

    The word ‘supplier’ is actually a bit misleading, because most people’s electricity is supplied by the National Grid. The companies you pay for your electricity and gas should really be called ‘sellers’, because that’s all they do – they sell the energy in the Grid to you. That’s great for consumers, because it means no matter who sells us the energy, it still comes from the Grid. No interruptions of supply, no visits from engineers – just a different name on your bills.

  • I rent my home. Does that mean I can't move to a clean energy supplier?

    If you pay the energy bills, then it’s your choice – if you want cleaner, cheaper energy, you can have it! You can see Ofgem’s guidance for tenants here. If your landlord pays the energy bills, then why not ask them if they’ll switch (and let them know they could save money in the process!).

  • I have a smart meter with my current supplier. Can I still switch?

    You can still switch, but you may have to provide manual meter readings to your new supplier for a while. Most suppliers will soon be rolling out a new generation of smart meters which will allow you to switch providers without losing functionality – if you don’t have one, you can ask your new supplier to install one.

  • I'm on a pre-payment meter. Can I switch?

    Unfortunately green energy options are currently limited for households on pre-payment meters, and only some of the suppliers on our panel – including Bulb – support them. There are signs this is changing, however, and we expect other energy suppliers to be offering tariffs to homes on pre-payment meters in the future. In the meantime, if you’re on a pre-payment meter and need to secure the most competitive tariff, you may be better off using a whole-market price comparison engine like EnergyHelpline.

  • I have (or am thinking about getting) solar panels – can I still switch?

    Yes, absolutely. You are free to switch your supply to a different provider in exactly the same way as a house without solar panels. Your Feed In Tariff arrangement will remain unchanged.

  • When will the switch actually take place?

    Once you’ve completed your switching application on our site, we’ll send your details to your new energy supplier. They will in turn contact your current supplier to let them know you’re moving, and set a date for the switch (which they’ll tell you about in advance). Then on that day, you’ll stop paying your old company for your energy (they’ll send you a final bill up to that date), and start paying the new one. Simple!