The higher and more expensive a vehicle's trim, the more plentiful its features are. But some features add weight and complexity, which can affect performance in various ways. In the case of the forthcoming Nissan Leaf E+, getting fancy could sacrifice more than 20 miles of range.

In its base trim, the Nissan Leaf E+ may offer 25 miles more range than higher trims, Automotive News reports, citing a test certificate from the California Air Resources Board (CARB). Taking CARB's Urban Dynamometer Driving Schedule and adapting it to EPA numbers, the base Leaf E+ should pack a range of about 255 miles, with SV and SL trims coming in around 230, by AN's estimates.

As AN notes, Nissan's own estimates are slightly lower, at 226 miles for the base trim and 215 miles for the SV and SL trims. The majority of this discrepancy is likely weight-related, as the base Leaf E+ is some 70 pounds lighter than the other models. The same thing has happened with gas-powered cars in the past, too.

No matter the trim, though, all models receive Nissan's ProPilot Assist semi-automated lane-holding system, in addition to a beefier electric motor that's more powerful than the one on the short-range Leaf.

The automaker "downplayed the CARB estimates" in AN's report, reiterating that the EPA has not yet published its official estimates. When asked to comment on the report, Nissan made the same points, including pointing out weight differences between trims and just how different EPA and CARB measurements are. We shouldn't have to wait too long for the EPA to put out its numbers, though, since the vehicle arrives at dealerships this spring. It will be interesting to see just how big the gulf is between the base Leaf E+ and its higher trims when those numbers become public.

Update, 8:56 a.m. PT: Added manufacturer comment.