Ford’s new F-150 Lightning — the electric pickup truck that can back up your home in the event of a power outage — is 17% cheaper to buy than the gas-powered version of the vehicle. That’s according to a new analysis that examines some of the most popular cars and trucks in the US, then compares the cost to the closest electric equivalent.

“When you’re buying a vehicle, it’s really hard to know what the total cost will be over the life of the vehicle,” said Tom Taylor, policy analyst at Atlas Public Policy, the organization that conducted the analysis. “So this is part of giving people better data to help them reconsider that decision. And then also to simply challenge the prevailing view that electric vehicles are more expensive.”

Others have looked at the cost differential between electric and gas vehicles in the past, but this is the first calculation that looks at specific models and compares costs over an expected eight-year service life. The gas version of the Ford F-150 is the best-selling vehicle in the country and has been for more than four decades. The F-150 Lightning could become the best-selling electric vehicle. (When Ford stopped taking reservations last December when it started production, 200,000 people had signed up.) The base model starts at $39,974, about $10,000 more than its petrol twin. But the $7,500 EV tax credit lowers costs. The analysis did not address government incentives, which may help more. In Maine, for example, there is a $2,000 rebate for electric vehicles, and low-income customers can get a $5,500 rebate.

The real cost benefit comes over time as it costs less to charge the truck than buying petrol, and it also becomes cheaper to maintain as electric vehicles have fewer moving parts. The same applies to other electric cars. “When it comes to fuel costs, there are significant savings for electric vehicles,” says Taylor. “It depends a bit on what vehicle and class it is. But if we look at a light sedan, for example, it’s a very cheap sedan and the fuel cost is effectively 50% of the fuel cost for one [internal combustion engine] Vehicle. So that’s a really significant saving.” (Calculations assume someone charges their vehicle at home most of the time, and public charging costs come from data from Electrify America.)

The analysis also compares the Honda CRV, one of the most popular SUVs, with Volkswagen’s electric ID.4. The electric SUV has 15% lower total cost of ownership. Owning a Tesla Model 3 is almost 5% cheaper than a similar Lexus. Chevy’s electric Bolt is 6% cheaper than a similar Toyota Corolla. (The cost savings are smaller on the cars, as Tesla and Bolt used up their share of the $7,500 EV tax credit.)

The real turning point for EVs is likely to come when the initial sticker price is also lower. That’s likely to happen relatively soon: A forecast by Bloomberg NEF suggests that in less than five years, without subsidies or accounting for fuel savings, electric vehicles could be cheaper to buy than their gas-powered counterparts.