Drivers failing to capture savings and environmental benefits from electric vehicle tariffs

Electric vehicle (EV) drivers are failing to capture the financial savings, or reductions in carbon emissions and pollution they are seeking from EV ownership, according to new findings from Good Energy, the renewable electricity company.

Commissioned to coincide with the launch of its new EV charge tariff, the research amongst fully electric and plug-in hybrid vehicle drivers reveals that reducing carbon emissions and pollution is the most common motivation for people to choose an electric vehicle, cited by 48% of them, alongside saving money (also 48%).

Electricity tariffs designed for EV drivers often offer lower electricity prices during off peak hours, typically at night, compared to standard tariffs. Requiring a smart meter, they enable customers to charge their vehicles when electricity demand is low, saving money on energy costs.

But while 71% of EV drivers say they charge their vehicles at home using one of these tariffs1, many are not getting the benefits they are looking for.

Many energy suppliers claim to provide ‘100%’ renewable electricity – including through their EV tariffs – while justifying their claims through Renewable Energy Guarantees of Origin (REGOs), which are often traded via a secondary market, meaning suppliers can source energy from fossil fuel sources, and then buy certificates to label a tariff as ‘100% renewable’.

Good Energy analysis of the Matched Clean Power Index – the platform that gives UK consumers the ability to see exactly how much of their electricity comes from renewable sources, hour by hour, all year – reveals that of 11 electricity providers offering specialist EV tariffs, seven provide renewable electricity 33% of the time or less. According to the index, some providers of EV tariffs provide renewable electricity 0% of the time.

The Matched Clean Power Index’s top performer for 2024 to 2025 is Good Energy, with a score of 88% renewable energy across 0.4 TWh of consumption.

Current regulation only mandates suppliers to match the total volume of renewable electricity certificates (REGOs) to the total annual electricity consumption, which means consumers may be using fossil fuel electricity at lower renewable production times, even though they are told they are on a ‘100% renewable’ tariff.

The new findings also suggest that many EV drivers are needlessly wasting money. At least 15% of them aren’t using EV tariffs, meaning they are missing out on off peak savings. A further 7% didn’t know what kind of tariff they used.

Recent research from Easee suggests that charging an EV during peak times when electricity is at its most expensive costs a typical high mileage driver using 40 kWh per week around £372 extra per year.

And, a Cornwall Insight report suggests that specialist off peak EV tariffs can offer motorists average annual savings of up to £1240 compared to petrol, rising to £1780 for high mileage drivers.

The savings could become even more important following reports that the Chancellor is planning on introducing a pay per mile scheme which would charge drivers of electric cars 3p per mile – costing them around £250 a year on average. It comes as a record proportion of used car buyers are choosing pure electric models, according to the motor manufacturers and traders.

Even some motorists with an EV tariff are losing out, as there are significant differences in the off peak rates charged across these tariffs, from 6.5 p per kWh to over 15p per kWH at the other end of the scale.

To help EV drivers who want to save money and help live a greener lifestyle, Good Energy has launched a new tariff with one of the most competitive off peak rates available. Featuring overnight rates of 6.6p per kWh between midnight and 5 am, the energy supplied is matched with 100% renewable electricity bought directly from Good Energy’s community of 3000 generators across the UK.

Donna Slater, head of propositions and pricing, said: ‘Electric vehicle drivers are motivated by environmental concerns and financial savings, but many of them are missing out on both. There is a large disparity between the best and worst rates on the market if they want to capture the benefits of charging their car off peak. And there is an even bigger disparity between the providers genuinely buying renewable electricity from generators, and those relying on a system using certificates and middlemen that can enable energy suppliers to buy most of your power from fossil fuels and sell it to you as ‘100% renewable’.

‘Our new EV tariff is for motorists who want peace of mind that their electricity is as renewable as it can be under the available infrastructure, and be able to charge their car overnight as cost effectively as possible.

‘Customers deserve more transparency around how suppliers source renewable electricity, which is one of the major roadblocks preventing British households and businesses from being able to play an active part in our net zero ambitions. We would like the government to mandate a much higher level of transparency so that people and businesses can be assured that choosing a green supplier helps to create a greener energy system.’

According to the research, other motivations for people to choose an EV include the convenience of being able to charge at home rather than visiting petrol stations (35%); performance benefits such as acceleration and quiet driving (26%) and the ability to access low emission zones without incurring charges (23%).

Being transparent about how power is sourced is key to Good Energy’s ethos. It launched the Good Green Supply earlier this year – setting sourcing principles that matter for transparency and growth of renewables – and called on other renewable suppliers to follow suit.

Its research suggests that consumers are confused by the lack of clarity over renewable electricity supply, duped into thinking the energy they use is 100% renewable when it is not. Over half of consumers (54%) with 100% renewable tariffs believe their supplier gets all of their electricity from renewable sources. Three in four consumers (73%) believe there should be stricter rules for transparency on how energy suppliers market their green claims.