BMW i3s vs BYD Dolphin Surf

The BMW i3s costs £19,020 more than the BYD Dolphin Surf. For that premium it adds 40 miles more WLTP range, 70 kW more power and a 4.2s quicker 0-62mph time. On EVcarsguide's combined category scores, the BYD Dolphin Surf comes out ahead overall.

The BYD Dolphin Surf is £19,020 cheaper to buy. Running costs are almost identical - about £184 a year either way, at 8,000 miles on an off-peak home tariff. Add 5 years of charging and the BYD Dolphin Surf comes out roughly £19,020 cheaper overall. These figures cover list price and home charging only - insurance, servicing, tyres and depreciation will move the real total.

EVcarsguide estimates a real-world motorway range of about 118 miles for the BMW i3s and 87 miles for the BYD Dolphin Surf - both below their WLTP figures, because sustained high speed is the hardest case for an EV. The BMW i3s goes roughly 31 miles further between charging stops. A rapid charge to 80% takes around 42 minutes in the BMW i3s and 30 in the BYD Dolphin Surf, so the BYD Dolphin Surf loses less time at each stop. So the BMW i3s stops less often while the BYD Dolphin Surf stops for less time - pick on which you would rather do.

The BYD Dolphin Surf is the easier car for tight UK car parks: it is 71 mm narrower than the BMW i3s. In a standard 2,400 mm bay that leaves about 680 mm of total clearance for the BYD Dolphin Surf and about 609 mm of total clearance for the BMW i3s. The BMW i3s also turns in a 0.5 m tighter circle, which helps with U-turns and multi-storey ramps.

Over a 8-year ownership window EVcarsguide's degradation model projects roughly 84% battery health for the BMW i3s and 90% for the BYD Dolphin Surf. That gives the BYD Dolphin Surf a modest edge in retained real-world range. The BYD Dolphin Surf's LFP-type pack tolerates daily 100% charging, while the BMW i3s's NMC-type pack lasts longest kept to about 80% for everyday use.