Now that it has finally delivered the first retail example of its I-Pace, Jaguar has released official range and MPGe estimates for this new luxurious electric crossover.

As we reported on Monday, the I-Pace is rated at 234 miles of range, a little short of the 240 that Jaguar indicated it was aiming for in earlier press drives.

For comparison, the base Tesla Model X, the closest competitor to the Jaguar I-Pace (though somewhat larger), has a similar range of 238 miles.

DON'T MISS: 2019 Jaguar I-Pace real-world review

It's not exactly apples-to-apples, though, as the Jaguar has a significantly larger battery pack than the base Model X—90 kilowatt-hours, versus 75 kwh for the base Model X. Generally speaking, smaller battery packs tend to contribute to better efficiency, because of reduced resistance-related losses within the pack; but that's clearly not always the case.

The Model X 100D, with a battery somewhat larger but closer to the Jaguar's size, is rated at 295 miles of range.

The smaller Hyundai Kona electric is estimated to get 258 miles of range from a much smaller 64-kwh battery.

2019 Jaguar I-Pace First Edition

Range isn't the only place the I-Pace falls a little short. To be delivered to retail customers, the I-Pace has to have official "fuel economy" ratings from the EPA as well. Electric cars are rated in MPGe, or the distance the car can travel on the amount of energy equivalent to one gallon of gasoline.

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In that score, too, the I-Pace lags. Its ratings of 80 MPGe city, 72 highway, and 76 combined look great compared to a gas car; but the base Model X is rated at 91 city, 95 highway, and 93 MPGe overall. Measured in the equivalent of miles per gallon, the energy saved at these high efficiency levels is minuscule, however. At the national average of 12 cents per kwh, (since it's impossible to account for every user in every place and rate plan), the extra cost to drive an I-Pace over a Model X could amount to $146 a year.

Jaguar claims acceleration from the I-Pace is a little faster than the Model X, at 4.5 seconds from 0 to 60, versus 4.9 seconds for the base Model X (note both are manufacturer claims and not verified by us]. The Jaguar is also lighter than the lightest Model X.

It's not clear why the I-Pace posts so much lower efficiency and range numbers than the larger, heavier Tesla with a smaller battery. It is worth noting that when we spent three days driving an I-Pace, the estimated range was remarkably inconsistent—more so than for other electric vehicles we've driven. Whether that's a hint or not, we'll likely find out as we learn more about the I-Pace.