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10 November 2020

Bulb Energy

Bulb Energy is a fast-growing green gas and electricity supplier which claims to offer affordable renewable energy. Should you switch to Bulb? We reveal all.
Bulb logo 2018 471927
Sarah Ingrams

Bulb Energy offers just one tariff, with 100% renewable electricity and carbon neutral gas. Bulb was set up in 2015 to ‘make energy simpler, cheaper and greener’.

It says that 10% of its gas is produced from renewable sources, while the remainder is offset by Bulb supporting carbon reduction projects around the world.

Bulb's variable tariff is usually among the cheaper deals available in England, Scotland and Wales. It doesn’t charge exit fees and says it will refund you if your old supplier charges you exit fees to leave and join Bulb.

Bulb Energy says it keeps prices low by investing in technology to reduce costs.

It has grown quickly and now has more than a million customers. In March 2020, it took on 9,000 customers from Gnergy when the smaller firm stopped trading. Homes with prepayment meters can now join Bulb.

Read on to find out how Bulb fared, or compare gas and electricity prices using Which? Switch to find out if you could save money with Bulb.

Bulb customer score

Bulb Energy came joint-third out of 35 energy companies rated by 7,355 members of the public in the annual Which? customer survey – the broadest, most independent, view of energy companies out there.

Its customers gave it the same score as Pure Planet, another firm offering 100% renewable electricity and focusing on digital service. Keep reading to find out why.

Bulb score breakdown

The graphic below shows the breakdown of its score in our latest survey.

Scroll down to read our verdict on Bulb, plus what customers think about different aspects of its service.

Find out how Bulb compares with other energy firms in our guide to the best and worst energy companies.

Which? verdict on Bulb 

Bulb has gained customers quickly since its launch a couple of years ago. Indeed, half of its customers in our survey said they switched to it in the past year. In contrast, just 10% of British Gas customers in our survey joined it in the last year.

Its rapid growth hasn't affected Bulb's ability to keep its customers happy, as shown by its consistently high ranking in our survey over the three years it's been included.

This year, Bulb only missed out on the top spot by five percentage points. Customers were most impressed by its complaints handling and the accuracy of its bills, both of which received five-star ratings. Bulb was one of only two firms to get the highest, five-star, rating for resolving complaints. The other was Octopus Energy.

Customer feedback shows that Bulb does a good job on creating clear bills, its customer service, digital tools and value for money.

Bulb also has one of the lowest levels of complaints among companies included in the survey, and resolved almost all the complaints it received in the first six months of last year within eight weeks. 

While that may not sound terribly speedy, the worst companies resolved less than 80% in the same time period. 

Bulb answered calls in just under 10 minutes on average (9 minutes 56 seconds) in our latest snapshot investigation into energy companies' call-waiting times. This was much faster than last year (19 minutes 2 seconds) but not as fast as the overall median average of the 31 companies we phoned (5 minutes 57 seconds). 

It took a similar amount of time for Bulb to answer live chat, 9 minutes 29 seconds, against an average of 3 minutes 4 seconds for all companies we contacted this way.

Pros: Customers rate it excellent for handling complaints and accurate billing

Cons: Slow to respond on the phone in our snapshot investigation, live chat often unavailable

Bulb electricity sources

Bulb Energy says 10% of its gas is ‘green’. This gas comes from biomethane produced from organic matter such as sewage and manure. The rest is carbon offset.

Discover how much money you can cut from your energy bills. Use Which? Switch to compare gas and electricity prices.

Bulb Energy in the news

August: Bulb paid out £1.76 million to around 61,000 customers in August 2020 for failures relating to switching, billing and not properly maintaining its Priority Services Register. Regulator Ofgem said Bulb has since made changes to improve its processes. Most of the payment comprised compensation and refunds, as well as a £157,350 payment into the energy industry voluntary redress fund to support vulnerable customers.

March: Bulb took on 9,000 customers from Gnergy when the smaller supplier stopped trading. It will odder a competitive tariff, energy regulator Ofgem says, plus honour customers' credit balances and any owing to existing and former customers.

February: While other firms were announcing price rises, Bulb told customers it would lower its gas prices, saving £20 per year, on average. Bulb explained that wholesale gas price have dropped since December, so it’s ‘passing on the saving to our members’.

December: Bulb announced that it had 870,000 customers and that its gross profit rose from £1.1 million to £12.1 million in a year. But it revealed that its losses grew faster in the same time period, which it said was due to the cost of growing its customer base and developing new technology.

November: Customers faced the third price rise of 2018, increasing the price of its tariff by 11.1%. As a result, the average home will pay £102 more per year.

Bulb said that wholesale energy costs had ‘gone up substantially’ since its last price increase in June – and have risen nearly 50% over the past year.

June: Bulb announced its second price increase of the year; adding £44 per year to the average bill from August.

Bulb blamed ‘substantial increases in the wholesale cost of gas and electricity’ for the price increase, affecting all of its 450,000 customers.

February: Bulb announced a price rise of 2.8%, on average, for all of its dual-fuel customers, increasing a customer’s typical bill by £24 per year from April.

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