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Range Rover Si4 P400e PHEV Review

The Range Rover Si4 P400e PHEV is a 100mpg Range Rover: it can drive on zero tailpipe emission electric power for up to 31 miles, and it can still drive up a mountain…

  • Range Rover Si4 P400e PHEV
  • Range Rover Si4 P400e PHEV
  • Range Rover Si4 P400e PHEV
  • Range Rover Si4 P400e PHEV
  • Range Rover Si4 P400e PHEV
  • Range Rover Si4 P400e PHEV
  • Range Rover Si4 P400e PHEV
  • Range Rover Si4 P400e PHEV
  • Range Rover Si4 P400e PHEV
  • Range Rover Si4 P400e PHEV
  • Range Rover Si4 P400e PHEV
  • Range Rover Si4 P400e PHEV
  • Range Rover Si4 P400e PHEV
  • Range Rover Si4 P400e PHEV
  • Range Rover Si4 P400e PHEV
  • Range Rover Si4 P400e PHEV
Green Car Guide Rating: 9/10

Key stats

  • Model/Engine size:  Range Rover Si4 P400e PHEV
  • Fuel:  Petrol-electric plug-in hybrid
  • Fuel economy combined (NEDC):  101 mpg


  • It’s a Range Rover – which means first-class travel
  • It can drive on electric power for up to 31 miles (officially)
  • It can still drive up a mountain
  • It still drives well when the battery is depleted

Range Rover Si4 P400e PHEVRange Rover Si4 P400e PHEV


It wasn’t that long ago when a 100mpg Range Rover was pure fantasy. Yet such a vehicle is now on sale. Of course the plug-in hybrid electric powertrain is the secret to achieving the 100mpg figure, but what happens when the battery is depleted? Can the remaining source of propulsion – a 2-litre petrol engine – really enable this Range Rover to still drive like a Range Rover?

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Range Rover Si4 P400e PHEVRange Rover Si4 P400e PHEV

Design & Engineering

The Range Rover Si4 P400e PHEV has a 300PS 4-cylinder, 2-litre petrol engine along with a 116PS electric motor (housed in the ZF automatic eight-speed transmission) and a 13.1kWh lithium-ion battery. There’s also all-wheel drive, a twin-speed transfer box, and electronic air suspension to provide increase ride height (giving up to 221mm of ground clearance).

Externally it looks exactly the same as any other Range Rover – apart from a very small P400e badge on the tailgate. This means that it retains the classic Range Rover styling. Because this is such a large car, it comes with 21-inch wheels, so they’re not dwarfed by the huge body.

The interior is also virtually identical to any other Range Rover, apart from an EV button and some additional read-outs on the dashboard about electric driving range etc. This means that the interior is a very upmarket place to be. A new feature is the Touch Pro Duo infotainment system with twin high-definition 10-inch touchscreens on the central console; satnav information is on the top screen, with car controls such as climate on the lower screen.

You charge the vehicle by plugging the charging cable into a socket behind the Land Rover badge on the front grille. The plastic cover for the charging socket doesn’t lock/unlock with the robust feel that you might expect for a Range Rover.

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Range Rover Si4 P400e PHEVRange Rover Si4 P400e PHEV

Range Rover Si4 P400e PHEV Driving Experience

Let’s start off with some reassurance: the Range Rover Si4 P400e PHEV is extremely refined in normal driving. If you’re in hybrid mode, then the car decides when to use the petrol engine and when to use the electric motor. Either way, the driving experience is Range Rover-like. When on pure electric power (which can happen up to 85mph), the car is even more quiet and refined than normal – which shouldn’t come as much of a surprise.

Perhaps what is a surprise is that the P400e drives so well when the battery is fully depleted, when there’s no electric torque to fill the gaps in the torque of the petrol engine. This is even the case when pressing on in the transmission’s S mode – the 300PS petrol engine is very responsive in such a large vehicle. You can just about notice the difference when setting off from standstill, but the rest of the time, amazingly, you’re not aware that it’s just a 2-litre petrol engine propelling a 2.5-tonne 4×4.

So the Range Rover Si4 P400e PHEV is very proficient on the road in hybrid, electric or petrol mode. But what about off-road? All our tests of Land Rover products include driving them up mountains, because the whole point of Land Rovers is that you can do that. Again, the 2.5 tonne Range Rover, even purely on its petrol engine (with a depleted battery), drove up a mountain as though it was just on smooth tarmac (and despite large, 21-inch alloys and low profile tyres, the P400e was returned to Land Rover with pristine wheels!).

So there should be no concerns about whether this car is capable with a 2-litre petrol engine. However it would have been even better using the torque of its electric motors off-road if we’d have had some battery charge left (the low range transmission can be operated in pure EV mode).

The Terrain Response 2 programmes feature a new Comfort mode and a Dynamic setting, as well as Grass Gravel Snow, Mud/Ruts, Sand, Rock Crawl and Eco options. You can raise the ride height by 40mm or 75mm.

Despite being a hybrid, the P400e has a 900mm wading capability. Land Rover says that for deep water wading, it is recommended that the Ingenium petrol engine is running to prevent water entering the exhaust system.

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Range Rover Si4 P400e PHEVRange Rover Si4 P400e PHEV

A button marked ‘EV’ allows you to control the powertrain. This gives you two options: EV (electric driving) or non-EV driving – in other words hybrid. In the latter mode, the car decides when it will run on the petrol engine or when it will use the electric motor.

If you enter a destination in the satnav then the Range Rover will use a Predictive Energy Optimisation (PEO) function to decide when the petrol and electric powertrains are used. In our experience this resulted in the battery charge expiring virtually exactly as we reached our destinations – so the system seems to work well if that’s the outcome you want. It’s less good if you still want some battery charge left when you arrive somewhere (such as a built-up area or, in our case, a mountain).

A SAVE function prevents the battery charge dropping below a pre-selected level, but there’s no button on the dashboard to select this – instead this feature is accessed via delving into the touchscreen.

The main touchscreen is wide and has clear graphics. There are many shortcut buttons under the screen, which can be a bit overwhelming when driving, yet a few more graphics showing what’s going on with the powertrain and state of battery charge/remaining range would be useful. The screens can also be slow to start up, and the satnav doesn’t allow to you quickly and easily zoom in and out – which has to be one of the most essential features of any new car due to the amount of crashes and delays on the UK motorways meaning that you need the ability to see ahead on the satnav.

The only other issue to report is that driving a Range Rover through multi-storey car parks can be a nervous experience. You’re constantly worried that you’re going to scrape the roof (even though a super-low setting can be selected for the suspension) and multi-storey car park layouts are definitely not designed to comfortably accommodate cars the size of a Range Rover.

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Range Rover Si4 P400e PHEVRange Rover Si4 P400e PHEV

Range Rover Si4 P400e PHEV Economy and Emissions

The official NEDC combined fuel economy for the Range Rover Si4 P400e PHEV is 101mpg, with CO2 emissions of 64g/km.

As well as being concerned about how the Range Rover would drive with just a 2-litre petrol engine, our other concern related to the real-world fuel economy. How far off the 101mpg would the Range Rover be on a long journey? And how far off the 101mpg would the Range Rover be on a long journey when it had no battery charge and was operating just on its petrol engine? The first question was answered at the end of a 122 mile journey from Manchester to Abersoch in Wales with the car fully loaded to the roof with a family and its luggage; on arrival the economy read-out displayed 37.1mpg, just as the battery charge disappeared. The answer to the second question was answered after the return 122 mile journey from Abersoch to Manchester, done with zero battery charge, so running only on the petrol engine, when the P400e returned 30.0mpg.

After a week of mixed driving, including two long journeys totalling 244 miles, some off-roading, and all local journeys carried out on electric power (with the dashboard read-out displaying 250mpg+), the average fuel economy was 42.2mpg – which is predictably nowhere near the official 101mpg NEDC figure – but still impressive for a 2.5 tonne Range Rover.

But what about official and real-world electric range? The Range Rover Si4 P400e PHEV’s official electric driving range is 31 miles. With a full battery charge, the car displayed predicted EV ranges of up to 29 miles (31 miles on one occasion). However in real-world urban driving the actual EV range varied from 16.5 to 21 miles. So the EV range display appears to be somewhat optimistic for urban driving; driving at a constant 30mph is likely to result in a more impressive real-world electric range.

With an 86-litre fuel tank, driving range is good; with a full tank and full battery, the dash was displaying a total driving range (petrol and electric) of 430 miles.

Of course you need to be able to recharge your Range Rover PHEV; this will take a few hours if using the recommended home charge point (charging time using a 32 amp wall box is officially 2 hours 45 minutes). Charging time will increase to 7 hours 30 minutes using the 10 amp home charging cable.

And we need to issue our standard 4×4 disclaimer: if you’re looking for the most efficient car, then a large 2.5 tonne 4×4 isn’t going to be top of the list.

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Range Rover Si4 P400e PHEVRange Rover Si4 P400e PHEV

Price and Model Range

The Range Rover Si4 P400e PHEV costs £86,965. Options fitted to our test car were 21-inch alloy wheels (£1,070), laminated front and laminated privacy rear side glass (£400), and domestic plug sockets (£105). The fixed panoramic roof and the CD/ DVD Player were no cost options.

The P400e is available in both standard and long wheelbase body styles.

You can also buy petrol and diesel Range Rovers, as follows: 258PS 3.0L V6 Diesel, 339PS 4.4L V8 Diesel, 340PS 3.0L V6 S/Charged Petrol, 380PS 3.0L V6 S/Charged Petrol, 525PS 5.0L V8 S/Charged Petrol, 565PS 5.0L V8 S/Charged Petrol SV Autobiography Dynamic.

Following the addition of the P400e, the SDV6 Hybrid Diesel powertrain is no longer available.

Of course there are potentially significant Benefit in Kind company car tax savings to be made due to the P400e’s BIK rate of 16% (compared with 37% for the standard Si4 petrol).

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Range Rover Si4 P400e PHEVRange Rover Si4 P400e PHEV


The Range Rover Si4 P400e PHEV is a highly impressive car. It looks like a regular Range Rover, it offers the luxurious interior environment of a regular Range Rover, and it (mostly) drives like a regular Range Rover. It can also smooth out a track up a mountain like a regular Range Rover. However it can also drive up to 31 miles on zero tailpipe emission electric power, and it can claim an official (NEDC) fuel economy figure of 101 mpg, with CO2 emissions of 64 g/km.

Our review set out to find the answers to two main questions. Firstly, can a 2-litre petrol engine propel a Range Rover in a suitably refined and progressive way when the battery is depleted? The answer is yes. The second question was how far off the official figure would the real-life fuel economy be on a long journey, both with a fully charged battery, and with a depleted battery? The resulting figures of 37.1mpg and 30.0mpg respectively were much better than expected.

So should you choose the Si4 P400e PHEV over the other models in the line up? Range Rovers are amazing long distance touring cars; for such use, you would imagine that one of the latest Euro 6, 3-litre turbodiesels would be a more appropriate powertrain than a plug-in petrol-electric hybrid. But of course diesels are being demonised for use in built-up areas – even though the primary problem with diesel emissions in many built-up areas stems from old diesel trucks, buses, vans and taxis.

Perhaps the P400e is primarily designed for cabinet ministers who can cruise around Westminster with zero emissions, then drive to meetings at Chequers on petrol power.

Anyway, the Range Rover Si4 P400e PHEV remains a highly impressive machine. It’s obviously debatable about whether a Range Rover can be described as being ‘green’, but the fact is that no other car exists that has the breadth of abilities of the P400e PHEV, and so, taking all aspects of the car into account, it achieves a Green Car Guide rating of 9 out of 10.

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Car facts and figures Range Rover Si4 P400e PHEV Review

  • Fuel economy extra urban (NEDC): N/A mpg
  • Fuel economy urban (NEDC):  N/A mpg
  • Test economy: 101 mpg
  • CO2 emissions (NEDC): 64 g/km
  • Vehicle tax rate (VED):  £325 year 1, £440 year 2 onwards (includes an extra £310 a year for a car with a list price of more than £40,000, to be paid for 5 years from the second time the vehicle is taxed)
  • Weight:  2509 kg
  • Benefit in Kind (BIK) company car tax liability (2018/19): 16%
  • Price:  £86,965
  • Insurance group:  50E
  • Power:  404 hp (total)
  • Max speed:  137 mph
  • 0-60 mph:  6.4 seconds
  • Torque:  640 Nm (total)
Paul Clarke

Review by:
Paul Clarke, GreenCarGuide Editor