The report from the Energy and Climate Intelligence Unit (ECIU) warns of the risk that slower roll-out of new EVs could reduce the size of the second-hand market, and force low-income drivers to pay more to continue running petrol cars.
The ECIU is calling on the government to increase its proposed level for the incoming zero-emission vehicle (ZEV) mandate to avoid this scenario.
The ZEV mandate will require UK manufacturers to increase the proportion of new zero-emission cars and vans they sell in the UK. The proportion has currently been set at 22 per cent for 2024, rising each year until 2035, when 100 per cent of sales must be zero emission.
However, this plan is set to lead to 2.1 million fewer used small and mid-sized EVs being placed on sale by 2033, compared with a scenario in which ministers adopt the car industry's "high" EV sales projections, ECIU predicts.
The non-profit points out an analysis from the Society of Motor Manufacturers and Traders which suggests that in a scenario where the take-up of EVs is "high", their market share would hit 34 per cent in 2024, and 60 per cent in 2027.
The ECIU estimates that a reduction in available used EVs would cost UK motorists around £9bn in missed savings by 2043 - based on calculations that small to mid-sized EVs can save their owners between £500 and £800 a year in running costs.
"Even with record-high electricity costs driven up by the gas crisis, EVs are still around three times cheaper to run than their petrol equivalents," said ECIU transport analyst Colin Walker.
"But with 82 per cent of car sales in the UK being second-hand, this market is critical if many more families across the UK are going to be able to access these savings.
"If government policy on new EVs goes slow, the growth of the second-hand EV market will be held back, potentially consigning families to more expensive motoring."
The ECIU believes manufacturers could choose to sell more of their EV stock in the UK if the country sets a tougher ZEV mandate than the European Union.
A Department for Transport spokesman commented: "We're working closely with industry on the path to all new cars being zero emission by 2035, and carefully considering any issues raised as we consult on our mandate.
"More widely, we've put more than £2 billion into helping consumers transition to electric vehicles."
Recent modelling by the RAC Foundation found that the reduction in total carbon emissions from cars necessary to meet the UK's climate change goals could be achieved without drivers travelling less overall.
"From the point of view of the planet, the next car people buy is critical," said RAC Foundation director Steve Gooding.
"For those thinking of going electric but wavering – perhaps put off by the up-front price – there is a case for pausing to see how things play out in the next year or two, rather than falling back to petrol."
The analysis found that a 40 per cent reduction in CO2 emissions from cars between 2021 and 2030 can be achieved by big changes in other areas, such as battery electric cars accounting for 35 per cent of the total car fleet in 2030.
Last week, the Society of Motor Manufacturers and Traders (SMMT) said that electric, plug-in hybrid and hybrid electric vehicle volumes were up 49.9 per cent to 28,329 units.
In 2021, the UK car industry saw the worst output for the month of July since 1956 as the sector struggled with ongoing staff shortages alongside strained supplies of semiconductors. The sector started to recover last summer as the global chip shortage began to ease.
During 2022, fewer than 9,000 public EV charging devices were installed in the UK, leading to claims that the infrastructure is not keeping up with demand.
To address this issue, the UK Department for Transport (DfT) has announced that 2,400 new chargepoints will be installed in locations across England using public and industry funding.
