Plug-in hybrids are getting smaller, it seems, as BYD launches the latest Dolphin variant. Simon Harris tests it out.

What is it?: Compact plug-in hybrid  How much?: From £20,000 (estimated)  Economy: 108.6-201.8mpg  Emissions: 32-60g/km

This slideshow requires JavaScript.

The small car sector is about to witness an unusual competitive experiment with the arrival of the BYD Dolphin G DM-i. While the commercial landscape for compact hatchbacks is currently populated by a handful of full-hybrids, mild hybrids and standard petrol engines, BYD is attempting to break new ground by introducing a full plug-in hybrid powertrain to this specific segment.

Prices start from £23,990 but it is worth pointing out that the entry-level Active model features a notably small 7.42kWh battery, limiting its pure electric range to just 25 miles. However, BYD UK anticipates that the higher-specification Comfort grade will be the most popular choice by far. As with the Boost model that sits below it, this version steps up to a much more substantial 18.3kWh pack, pushing the zero-emission range to a highly competitive 65 miles.

Behind the wheel, the initial driving experience feels pretty good. The powertrain relies on a naturally aspirated 1.5-litre petrol engine that functions primarily as a generator for a front-mounted electric motor. Because the engine is rarely tasked with driving the wheels directly, BYD has avoided a traditional turbocharger in favour of ultimate thermal efficiency. It operates on the Atkinson cycle (as with Toyota hybrids) and runs an exceptionally high 15.5:1 compression ratio. This setup ensures the car delivers an EV-led driving style, pulling away from a standstill with smooth, quiet authority. The transition between electric power and petrol intervention is remarkably seamless, making it a relaxed commuter tool.

Spending time with the car reveals a couple of distinct quirks. The most noticeable interior anomaly is the indicator noise. Instead of a standard, monotonous click, the system emits a dual tone that alters its pattern based on your intention. It switches from a high[1]-low chime to a low-high sequence depending on whether you are signalling left or right, a trait that once noticed, becomes a focal point.

We also discovered during the launch that the G in the nomenclature stands for ‘genius’. Whether that title is fully justified remains to be seen, not least because

BYD’s current product strategy in this segment looks slightly puzzling. Filling the compact car market with three separate models all carrying the Dolphin badge, including the standard Dolphin EV, the smaller Dolphin Surf city car, and now this Dolphin G DM-i, creates potential risk of customer confusion.

The positioning of this new hybrid becomes easier to understand if you look further down the line. We anticipate that the original Dolphin EV is the next model due for a significant makeover. A subsequent refresh could push the pure-electric version slightly higher up the price and specification ladder, which would finally allow the hybrid Dolphin G to make more structural sense in its market positioning.

The true potential for this vehicle lies with urban fleets. For operations requiring predictable, zero-emission city mileage without the immediate need to install a costly workplace charging grid, this competitively priced plug-in hybrid makes absolute sense.

In Brief:

Key fleet model: Comfort

For: Competent; comfortable; EV range

Against: Small battery version; confusing sector strategy

Summary: First compact hatch plug-in hybrid impresses

Also consider: Toyota Yaris; Renault Clio Hybrid; Honda Jazz