How well do you know your PHEVs from your Hybrids?

Updated: Jun 4, 2021

Boost Auto was talking to a large corporate a couple of weeks ago about their fleet, and their desire to be lower emissions and greener. The board had agreed that EVs were the way forward, and they had set their procurement team a clear goal (with a tight timeframe) about exiting their ICE (Internal Combustion Engine) fleet.

Two weeks ago the New Zealand Herald talked about 'Electric' sales in their Driven section, and listed which vehicles were selling well.

In both cases Hybrids were included, which were being confused with Plug In Hybrids. Which illustrates why it pays to be pedantic sometimes.

The pioneering Toyota Prius was launched globally in 1996, and from that spawned the Hybrid Synergy Drive (HSD), and the small badge that adorns millions of Toyota around the world. But HSD or Hybrid isn't electric. It has a battery only range of nil, cannot be recharged by a plug and can only be fuelled by petrol. In other words, it is an internal combustion engine car, with battery assist that helps provide additional power the vehicle and helps with stop start traffic to make the car more efficient, particularly in an urban environment. You might already know this, but clearly many don't.

Toyota RAV4 Hybrid has sold out with a waiting list 'longer than 6 months', according to the Toyota NZ website. This isn't because its a good car (it is) but is related to some large companies thinking they are doing the right thing and putting EV's on their fleet (when they aren't).

Here is a quick summary of the terms, and what they mean:

Hybrid (mild hybrid) - has a battery but typically 1.0-1.6 kWh. Only runs on petrol. Battery charged by regenerative braking only. About 20% more efficient and lower emissions than the ICE equivalent. About $3-4K premium over ICE.

Plug in Hybrid Electric Vehicle (PHEV) - has larger battery. Typically 10-15 kWh (Outlander 12 kWh, MG HS 16 kWh, new A-Class 15.6 kWh). Typical range 40-60kms on EV only. Needs plugging in at night - or else when battery is flat, runs only in mild hybrid mode. Range is suitable for 80% of commutes in New Zealand. As the battery is relatively small it is easy to charge at home without 7 kW home charger being installed. Over 70% more efficient than the ICE equivalent, and 65% more efficient than a mild hybrid. About $13K premium over ICE equivalent (and therefore around $10K more than a mild hybrid). Typically offers more power and performance than its petrol only sibling.

Battery Electric Vehicle (BEV) - has a larger battery again, from 36 kWh (Ioniq), or 40 kWh (Nisan Leaf) to 90 kWh (Tesla Model 3). No ICE components. Requires charging infrastructure at home or place of work, although 80% of BEVs have their primary charger at home. The batteries are simply too big to make 8A changing at home anything more than a stop gap solution - it takes too long. Significantly cheaper than an ICE (or PHEV) to service because a BEV has about 20 moving parts compared with an ICE with around1500 moving parts. About 20-25% of the fuel cost of an ICE. Zero emissions.

Then there are the BEV's with REX (Range Extenders) where their is a petrol engine, but the engine is not connected to the wheels. Instead the engine's role is to charge the battery which drives the electric motor. There are some pretty interesting vehicles out there that deploy this type of technology. But it is not mainstream, so we won't go too far down that particular rabbit hole.

So in simple terms if it doesn't have a plug, then it doesn't really count. There may be some practical reasons why a mild hybrid might be better than a diesel vehicle in some circumstances or usage types, especially around light commercial vehicles.

Make sure you and your team know the terminology and the definitions, if you want to make a real difference to your fleet's emissions.

And lastly, you can't just replace one fleet with another fleet; that would be missing the point. You need better utilisation of your fleet (regardless of motor and powertrain) to make a substantial difference. With fleet improved fleet utilisation you might even find the capital cost neutral; then the fuel saving is all upside.

Boost Auto is an automotive consultancy working in five main areas.

  1. Sales and Marketing effectiveness for brands and dealers

  2. Green fleet facilitation for large corporates

  3. Go To Market strategies for emerging brands

  4. Market Insights

  5. Business Planning and facilitation

You can contact us at