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Plug-in hybrid vehicles among the 'highest-polluting' company cars

Newly-released data from TMC highlights worryingly-high fuel consumption and emissions in real-world driving for hybrid vehicles.

The data has been released as official car registration figures for August show a 47% rise in hybrid car sales compared to last year, and some leasing companies report a 300% increase in orders for plug-in hybrids.

TMC’s real-world driving data shows plug-in hybrid vehicles (PHEVs) to be among the highest-polluting company cars in terms of greenhouse gas emissions during real-world use by corporate fleets.

The analysis has shown that their average CO2 output is 168g/km in day-to-day use. As such, the PHEVs analysed by TMC would attract the top rate of company car tax in three years’ time if they were assessed on their real emissions instead of on laboratory test results.

TMC analysed fuel consumption data on 14 models of hybrid and 7 models of PHEV. All the cars in the sample, representing 12 different manufacturers, are in regular fleet use. The data for the analysis came from TMC’s Mileage Capture and Audit system, which holds detailed records of fuel transactions and total mileage for each vehicle.

The PHEVs in the sample achieved an average of almost 45mpg compared with their average advertised consumption of 130 mpg. This average fuel use is equivalent to actual CO2 emissions of 168g/km. That compares with the cars’ advertised emissions (which determine the drivers’ benefit-in-kind tax rates), which averaged 55g/km.

Moreover, PHEVs in TMC’s sample tended to emit more CO2 in real-world driving than ordinary diesel company cars. Earlier this year, TMC analysed real-world fuel consumption and CO2 data of 20,000 conventional fleet diesels. The diesels’ emissions averaged 159g/km compared with the PHEVs’ average of 168g/km.

Drivers of standard hybrid cars used nearly 10% less fuel on their day-to-day journeys than drivers of the (theoretically more-economical) plug-in versions. The real-world fuel economy of the standard hybrids tended to be closer to advertised performance than that of PHEVs. In real-world use, drivers of plug-in hybrids consumed three more fuel than official figures would suggest.

’Fake’ low-emission cars

While TMC was compiling its analysis, Belgium’s government announced that it will abolish corporate tax breaks for what it calls ‘fake’ low-emission vehicles such as hybrid cars with limited zero-emissions potential. From 2020, plug-in cars in Belgium will be only granted tax relief on a sliding scale linked to their battery’s storage capacity in relation to the total weight of the vehicle.

UK company car drivers will encounter a similar tax regime from 2020, when benefit-in-kind tax concessions for electric vehicles, PHEVs and hybrids will be tied to how many miles the car can travel on battery power alone.

Paul Hollick, managing director of TMC, said: “There is a real risk that fleet managers are adopting a PHEV strategy for completely the right reasons but unknowingly actually increasing their fuel bills, while the only beneficiary is the driver paying lower BIK on the car.

“It is vital that a fleet deploys a mixed fuel strategy, using real world data or support from a company like TMC.

“Deploying PHEVs is not at all a straightforward decision for fleets. Managers need to allow for the fact that their fuel cost per mile can increase substantially on longer journeys. PHEVs can be a cost-effective choice where drivers cover only moderate mileages; but only if the cars’ batteries are recharged daily.

“On the evidence of our sample, one has to question whether some PHEVs ever see a charging cable.  In a lot of cases, we see PHEVs never being charged, doing longer drives and this is not a good fit for a lot of business car users. A robust PHEV deployment policy is essential.

“Of course, it is fantastic that drivers are latching onto the idea of PHEVs but it must be done for the right reasons. Until now, almost any vehicle with battery assistance tended to attract a generous tax subsidy. After 2019, only pure EVs will attract sizeable tax breaks.

“Hybrids and PHEVs will increasingly stand or fall on the strength of their total cost of operation in the real world. Our data sample, though small and therefore not definitive, clearly suggests that PHEVs as a class may struggle to maintain their appeal on a real-world basis.

“As hybrids lose their special tax status and conventional vehicles– especially diesels – face increasing air quality penalties, it will become harder for fleet users to identify cars sitting in the ‘sweet spot’ on running costs, range, taxation and emissions.

“Mobility managers will need access to more-complex data models, with comprehensive information on real-world fuel costs and emissions, to identify the best company car contenders in future."

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  • Mr.Bean - 20/09/2017 09:22

    Really! This isn't new and people who buy a car assuming it will do 135mpg, are in simple terms uneducated and should research before buying a car or anything. I'm tired seeing these articles coming time to time with no new facts. The only reason why people buy these cars is for BIK. Yes, some want to be green, but most is to save money.

  • Nigel Boyle - 20/09/2017 11:17

    The Mitsubishi PHEV is the biggest culpret. Advertised as a planet saver, but a big SUV with a petrol engin e that guzzles fuel. THat is apart from the first 10 miles of a journet when it runs on battery

    • Gordy - 20/09/2017 12:31

      Yes! Time to get rid of your Outlanders! Residuals.....! Only REAL world emissions will benefit us. Taking one hour to rapid charge to get 20 miles is a bit of a joke when new Leaf will do 230 or maybe 300+ with the bigger battery, for the same time on a rapid charger. Inefficient hybrids using charging points will only exacerbate the growing problem of charge rage. They are actually creating a problem. So is £315 tax for 5 years on EVs over £40 grand and the mileage / fuel rate debarcle for EVs doesn't reflect fairly in the initial outlay cost for EVs especially executives EVs. Come on government, get the sham hybrids off the roads and start rolling out chargers much more quickly (16 times more quickly please).

  • Ben Cowell - 20/09/2017 11:41

    A plug in hybrid has more weight of batteries to carry round, so when only running on fossil fuel there will be a weight penalty and associated increase in fuel consumption. The problem with all fuel economy tests is that existing tests use such a light throttle that every vehicle is much better than "real life" or the forthcoming emissions tests.

  • Peter Egerton - 20/09/2017 11:44

    @Nigel Boyle Usually PHEVs will balance between electric and petrol power depending on the situation. So it's not all electric and then all petrol. For example, from a standing start the electric motor will work hard initially, then the petrol engine will come in. At constant speed the electric motor will come back in to maintain the vehicle's speed. It's possible that drivers aren't fully charging their cars and are only using the petrol engine.

  • 30 mile range - 20/09/2017 11:50

    Why has it taken so long to realise this? The "success" of the Mitsubishi Outlander PHEV is due to one thing; low BIK for the driver. PHEVs may be viable for low mileage office based commuters but for most higher mileage company car drivers they are more expensive than an equivalent diesel, with mid-20s MPG not uncommon. Take away the electric motor and the Outlander PHEV is a virtually worthless mid-sized petrol SUV. How come so called professional fleet managers were duped? Or is it just ticking the "we operate a green fleet" box like the majority of public sector fleets. Environmentally friendly? Probably not, expensive and poor value, almost certainly, but that "green" box is ticked so our conscience is clear.

    • Paul Holden - 20/09/2017 12:12

      If we had dismissed the first internal combustion engines because they were less reliable and slower than a horse, were would we be now ? The process from one technology to another has to start somewhere. Majority of professional fleet managers were and are aware of the shortfalls but obviously the tax advantages are out their for that exact reason to promote and encourage change. No one was duped only encouraged to take part in progress .

  • Alan Baker - 20/09/2017 11:54

    Whilst I understand the comment from TMC, I think the headline is a little too broad tarring all PHEV;'s with the same brush. We run 170+ PHEV's and do not have the same problem with most of our drivers. I run a Passat GTE and achieve 85+mpg regularly but it has a modest yet powerful 1.4T petrol engine.

    • john4870 - 22/09/2017 17:35

      Well done for a balanced view - need more of these.

  • Robberg - 20/09/2017 12:44

    I'm pleased to see that this is finally getting the publicity it deserves. We have one Outlander PHEV on our fleet and the driver chose it solely for tax purposes and is aware of the real world fuel consumption; 20mpg in his case. It is a perk car and there is no fuel reimbursement so it was allowed. Also, would people please stop using the phrase "environmentally friendly" as there is no such thing. At best they are less environmentally unfriendly.

    • Bob the Engineer - 21/09/2017 00:12

      I have the same car and to get 20mpg is really very difficult, you have to rag it like you being pursued by the police! Anyone driving like that, fuel consumption should be the least of your worries!!! I manage 40mpg even on longer trips, evenings and weekends all the family use it locally almost entirely on battery. I suspect our long term total emissions are better than would be the case for most vehicles. And without all that diesel soot going in the air!

  • john4870 - 22/09/2017 12:29

    As a Prius PHEV user (older model) I still get regularly 65-70 mpg - that's without the 'electric only' bit. Whilst it will do 15 miles just electric, in 'hybrid' mode with a larger battery and electric motor than the 'normal' Prius it uses the battery/electric motor far more often and to higher speed than 'normal' Prius so it is not as black & white (sorry, black & green!) as you might think. Having used 4 x Prius for 10 years and 300,000 miles before the PHEV, I know Prius very well. Great cars - but more sensitive to driving style than some cars, so if you respect them or thrash them the fuel figures will reflect that. As always the 'nut behind the wheel'...!

  • rtfa - 24/09/2017 09:22

    "PHEVs can be a cost-effective choice where drivers cover only moderate mileages; but only if the cars’ batteries are recharged daily." -DOH!!! thats the whole POINT of PHEVs - you will get those 135 miles figures of you drive it as it should be driven. But that figure might be just as false as the MPG figures given out for normal cars

  • Iain - 28/09/2017 11:31

    Just taken delivery of Passat GTE and had to do an 80 mile round trip before i had a chance to charge it up. Pleasantly surprised to find it averaged 48mpg running on petrol and regenerated electricity from braking. Have since plugged it in (couple of hours at a time) which gives enough charge to get to work and back, and, over a week, should take me to fully charged. It means I have commuted this week just on electricity, so the PHEV is working here, and the small. but powerful, petrol engine appears efficient if treated with a little care and respect ...

  • John Burns - 05/12/2017 10:10

    One of the refineries in the UK uses electricity, generated by mainly fossil fuels, to the level of Leicester and Coventry combined. Then this petrol, which took lots of fossil fuel to extract it from the ground and then transport it around the world, and then refine it, is then put into the tanks of cars polluting yet again - but this pumping out toxic gasses in front of the lungs of millions of people. Eon Musk said there is enough electricity generation available to charge all cars if they were all 100% electric vehicles. When petrol refining drops the EVs use the electricity "directly". EVs and plug-in hybrids are massively cleaner all around than 100% internal combustion engine cars.

  • Desmond Walsh - 16/09/2020 21:23

    Carrying two transport technologies around and the extra weight means that these are inefficient vehicles. Why is there not production of small lightweight electric vehicles for city/suburban use here in Europe. There are small cheap eVs advertised on the internet ( Chinese ) but no user comments on them .I run a 10 year old Nissan Micra and get 66 to 68 mpg on short and long routes. There is of yet no eV available suitable to replace it . Definitely not a hybrid . Des Walsh , Cork , Ireland

  • Filipe - 24/09/2020 22:54

    It depends on the auto maker. In every sectors there are companies that make fake products. But that doesn't mean HYBRID isn't an huge technology. So regulators just have to test the real pollution.

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