Black cabs are going green

The LEVC Tx e-City
The LEVC Tx e-City

The black cab: a London icon recognised the world over and a vital part of London’s transport system. Convenient and functional, the vehicle is a deservedly popular sight on London’s roads. And also the safest means of transport by far, according to Transport for London (TfL) data. But London’s black cabs also contribute a significant amount to the levels of atmospheric pollution in the city, levels which greatly exceed EU Air Quality permitted limits. According to TfL, the taxi fleet create some 16% of the hazardous Oxides of Nitrogen (Nox) pollution in central London.

In order to address this, The Mayor’s Taxi and Private Hire Action Plan published in 2016, announced that the City intended to establish the world’s greenest taxi fleet. The first stages of this ambitious plan are already in place: from 1 January 2018, all new taxis have had, by law, to be diesel-free and zero energy capable. In other words, capable of running entirely on electric power for a minimum of 30 miles, backed up if necessary for additional range only by low-emissions petrol engines. Achieving this zero-energy range without compromising the black cabs’ traditional benefits of tight turning circle, wheelchair accessibility and good luggage space present a tough challenge to taxi designers, who have made relatively little change to the design of their product since its origins as the Austin FX3 cab just after World War II.

Perhaps the threat of this major product change was a challenge too great for the incumbent cab manufacturer, the London Taxi Company, who in 2012 went into administration. However, some assets of the company were bought by Geely, a relatively unknown but rapidly growing Chinese business who had already bought, in 2010, the struggling Volvo car business from Ford.

The Chinese vehicle industry has set its sights on becoming a dominant player in electric vehicles, a target which is well on the way to being achieved. For example, whilst London presently have less than 200 electric buses on the streets of the capital, one Chinese city alone – Shenzen – have over 16,000!

Geely, even before the Mayor’s green taxi plans were announced, recognised the potential to develop an electric taxi for London, and have to date invested over £325 million in their new business, called the London Electric Vehicle Company, or LEVC, based in Coventry, developing a groundbreaking product which is now starting to see service in London. Sensibly, in view of the iconic appearance of the traditional black cab, LEVC have maintained an almost identical external appearance for the new electric cab, yet under the skin lies a radically different product, with an all-new lightweight structure to offset the additional weight of batteries, motors, inverters and cabling.

The new cab - on the right, little changed visually from the outgoing diesel model.
The new cab – on the right – little changed visually from the outgoing diesel model.

LEVC have gone back to basics to understand and analyse the way in which a cab is used by its driver and passengers, and have radically redesigned it to bring it right up to date. As an example, they identified that, whilst the then-current TX4 diesel cab was wheelchair-capable, wheelchair access was a little cramped. The new cab, therefore, gained an extra 200mm in wheelbase, all of which is available to increase the passenger area, particularly to ease wheelchair space, the access to which is aided by an inbuilt wheelchair ramp. A further benefit to both wheelchair and able-bodied passengers is that the floor is both flat and considerably lower, as it no longer needs a propellor shaft underneath it. Coupled with wider opening doors and a higher roofline, this results in a simple, practical layout for all passengers, whether wheelchair users or not.

Creature comforts have not been forgotten either: the passenger compartment features a 230V AC power socket for laptops, two USB charging points and onboard WIFI, all topped off with a huge panoramic roof.

Such a significant wheelbase increase has always been considered impossible without compromising the black cab’s famously tight turning circle, yet LEVC has succeeded in achieving exactly that by redesigning the front suspension to provide significantly increased lock angles and working with their tyre supplier to produce a tyre which will withstand those angles. To put this into perspective, the front wheels turn to 63° compared to 38° in a typical SUV – so that the taxi can turn in the road between two walls not more than 8.5 metres apart, without reversing. One wonders whether Lotus, another Geely purchase with particular strengths in suspension design, had a hand in achieving this part of the LEVC development programme!

The driver hasn’t been forgotten either. The traditional cab’s drivers compartment is a pretty cramped place, due to the need to provide a rigid partition between the driver and his passengers, so LEVC have taken advantage of that additional wheelbase by having a dog-leg in the partition, with the section behind the driver set back to provide him or her with increased leg-room. The driving compartment has been brought right up to date, as well, by the selective use of suitably modified parts from the Volvo parts bin. The Volvo origins of the driver’s seat, for example, are clearly recognisable to any Volvo driver. And nothing wrong with that, for Volvo is recognised as having some of the most comfortable seats in the business.

Drivers compartment of the electric cab will be familiar to many Volvo drivers.
Drivers compartment of the electric cab will be familiar to many Volvo drivers.

Another clever touch shared with Volvo cars is the use of the big portrait-format Sensus touch-screen alongside the driver and their digital instrument panel in front of him. Again, these items are repurposed to incorporate specific taxi features. Why is this use of Volvo-derived kit important? Simply because development of such items is incredibly expensive, making it normally unrealistic for low-volume vehicles such as the black cab. By piggy-backing Volvo’s spend in this technology, the cab driver benefits significantly, the previous cab being distinctly agricultural in comparison.

Indeed, quality and refinement targets for the new cab were set by benchmarking against premium MPVs (not typical taxis). This led to the selection of materials which give a premium look and feel, whilst being hardwearing enough for the demands of cab use.

Use is made of Volvo parts under the skin as well, capitalising on Volvo’s present intensive development programme for electric vehicles, including their well-proven 1.5 litre 3-cylinder petrol engine. That’s not to say that the new cab is little more than a disguised passenger car, however, for every component used in the cab has been tested using a specially developed “TaxiDur” test – components (for example rear door hinges) undergo test cycles 10x – 20x longer than on typical passenger vehicles.

The electric Tx e-City cab undergoing hot weather testing in Arizona .
The electric Tx e-City cab undergoing hot weather testing in Arizona .
Cold climate testing of the new cab took place in Norway. Photo C. Patrick Gosling
Cold climate testing of the new cab took place in Norway. Photo C. Patrick Gosling

This includes over a million miles of final durability proving – in the most demanding of scenarios – in all climate conditions, with a final testing leg completed with drivers in London last year.

This includes over a million miles of final durability proving – in the most demanding of scenarios – in all climate conditions, with a final testing leg completed with drivers in London last year.

The small petrol engine acts as a “range extender” to recharge the 31kWh battery pack, which is mounted under the luggage area alongside the driver. The batteries provide power to a well-proven Siemens electric motor mounted on the rear axle.

The e-City's hi-tech electrics are tucked away below the floor and under the bonnet.
The e-City’s hi-tech electrics are tucked away below the floor and under the bonnet.

Flexible charging options

One area of concern for anyone contemplating an electric vehicle is that there is presently a proliferation of incompatible vehicle charging connections, a situation which will surely result in some of these falling by the wayside in a classic VHS versus Betamax situation. LEVC have neatly sidestepped this by providing not one but two fast charging ports for the currently most common fast charger types, CCS and CHAdEMO. It is understood that the ports can be upgraded to take advantage of any connector developments. Between them, the connectors are compatible with a wide range of charging stations outputs, from 3kW to 50kW.

One of the two charging ports fitted to the e-City.
One of the two charging ports fitted to the e-City.

The new cab will also be an even safer place for driver and passengers, as it uses world-leading accident avoidance systems using Volvo’s latest technology to reduce accident risk. This includes Speed Assistance, Autonomous Emergency Braking and Lane Departure and Forward Collision Warning. If the worst does happen, the occupants are protected by an extremely strong, rigid body shell with crash protection to the highest international standards.

Additional occupant protection is provided by three-point seatbelts with ISOFIX mounting points and energy-absorbing headrests, multiple driver and passenger airbags, and wheelchair restraints designed to meet ISO 10542 standard.

Plenty of room for all in the new cab.
Plenty of room for all in the new cab

The basic operational principles of the black cab haven’t been forgotten, either. LEVC analysis indicated that the typical cabbie lives outside central London, driving daily into the city and then covering typically 100-120 miles of fare-carrying duties before heading home at the end of his shift. It is these city-centre miles which London’s Mayor wants to see driven on electric power, the start and finish of shifts outside the city centre being less critical.

The typical operating procedure for the new cab is designed around this duty cycle. The intention is that the cabbie charges his vehicle overnight at home. If for example, he has a dedicated 7kW home wall box, the battery will be charged in 4 hours. He then drives into town in the morning using petrol power, switching to electric-only running when he arrives in the city. The 31kWh battery has a range of up to 80 miles, meaning that the cab will easily get to lunchtime without needed recharging. A quick fast charge at lunchtime will replenish the battery by 80% in 30 min on a 50kW rapid charger. This then sees the battery topped up enough to complete the rest of the days’ city-centre duties.

If, however, the cabbie gets a “money job” – an extended airport run – at any time of day, the cab can switch when necessary to petrol power, with a petrol-only range of 297 miles from its 35-litre fuel tank. Interestingly, even running on petrol only, the new cab is more fuel efficient, at a claimed 36.7mpg, than its diesel forbear, which could manage only 33.2mpg.

More cost effective for drivers

Regardless of how technologically advanced the new cab may be, it will not attract the hard-earned cash of the average cabbie unless it is cost-efficient. LEVC think their vehicle should at least break even over a typical 5-year ownership period compared to the traditional diesel cab. Although currently around £10,000 more to buy than the outgoing diesel model, the average cab driver should save £100 a week by moving to the new vehicle, based on the average mileage of 120 miles per day. Servicing costs should be cheaper, too, as service intervals jump from 12,000 to 25,000. and, should the worst happen, the new cab is designed to be quicker to repair meaning less downtime.

Many people worry about battery life on electric vehicles, but to give customers confidence the battery is covered by a class-leading five years, unlimited mileage warranty. In reality, LEVC’s engineers confidently expect a 15-year battery life due to good thermal & overload battery management. Electric vehicle batteries don’t like being fully charged or discharged, so the taxi battery pack is set up to charge to only 80% of its maximum capacity, and similarly, a few per cent of charge remains even when the batteries appear discharged according to the gauge. This is similar to the philosophy used very successfully by Tesla.

Impressive performance

Most electric vehicles have a surprising amount of get-up-and-go, due to peak torque being available from a standing start. The taxi is no exception, indeed it can accelerate impressively. In fact, on our road test, it left a small Italian / Japanese sports car standing!

Not only that, the ride was far smoother than the traditional black cab, with no tendency to the pitching and wallowing which can be a hallmark of some electric cars given the large mass of their batteries.

A key part of the efficiency of any electric vehicle is in making good use of brake energy recovery, and here the taxi offers two levels of regeneration, which are selected by flicking the stubby “gear lever” either left or right as desired.

Built in Britain, ready for the world

LEVC’s new site is the first new car plant to be built in the UK for over 10 years and is the only major car plant in the UK dedicated to electric vehicle production. Their £325m investment is creating more than 1,000 new high skilled, high-quality manufacturing jobs, including 200 engineers and around 30 apprenticeships. Impressively, over £200m of this investment has gone into product development.

Production of the new cab gets under way in LEVC's purpose-designed factory.
Production of the new cab gets under way in LEVC’s purpose-designed factory.

The 37,000 square metre site – the size of 17 football pitches – has a capacity to build over 20,000 vehicles per year to support LEVC’s eventual planned product range.

Despite the apparent Chinese (Geely) and Swedish (Volvo) involvement, by value a third of the vehicle’s content is sourced directly in the UK, a significant increase from the previous vehicle, and the project has seen the re-opening of an aluminium plant in Wales to deal with the increased demand for UK sourced aluminium.

The electric taxi is the first vehicle to be produced at the site and will be followed by a new electric light commercial van with the aim of becoming the urban commercial vehicle provider of choice.

Following the taxi off the production lines will be the LEVC electric van.
Following the taxi off the production lines will be the LEVC electric van.

Overseas orders are growing

So far, there are about 600 of LEVC’s TX eCity models on the streets of London. And soon the new electric taxi will become a common sight not only in London but also around the world. The first international orders – to the Netherlands, Amsterdam, Berlin, Hamburg and Oslo – have already been shipped, whilst Paris has also recently announced plans to take the new cab. The move into Paris is timely, as Mayor Anne Hidalgo is on an aggressive drive to improve air quality in the city and reduce private car use.

The Tx_e-City electric taxi will soon be a common sight on the streets of Paris.
The Tx_e-City electric taxi will soon be a common sight on the streets of Paris.

What does the future hold?

The new electric taxi, as we have reported here, is an excellent product, and a brilliant solution to the emissions problems facing not only London but almost every city worldwide so should deservedly have a great future. Inevitably, competition will appear and give the new cab a run for its money. Uber, for example, the bete noire of the licensed London cab market, have recently announced that they are increasing fares in London by 15p per mile in 2019 to fund the purchase of electric vehicles, whilst an electric cab from Nissan will shortly make an appearance.

The greatest problem to a wider uptake of the taxi in London could, perversely, be self-inflicted by the authorities at both Government and local level, the very people who are calling for a significant reduction in emissions. TfL has, on the one hand, set out to assist the development of the electric cab market by the planned introduction of 300 new rapid charge points by the end of 2020. With the other hand, though, they have apparently set the price of a charge from these at a high level of 22p per kilowatt, compared to the 10-12p per unit paid for domestic electricity. Changes to central Government policy could also threaten cost-effective electric operation: as electric vehicles become more popular, the tax income from petrol and diesel will drop dramatically. The Government will surely, therefore, look for an alternative, and many pundits predict that some form of per-mile road pricing is on the horizon. All of this makes realistic operational costings for cab owners tricky, to say the least.

The situation is made further complicated by the fact that some of the more recent diesel cabs can legally remain in service until they reach the ripe old age of 15 years.

So, the rate of take-up of the new electric taxi has not yet been as rapid as had been hoped. Although the number of vehicles (600) in operation to date is impressive, there is a long way to go before all of the 21,000 strong London cab fleet are electrified, unless TfL and/or central Government do more to encourage their uptake and so help to reduce the emissions levels of the city’s streets.

Old versus New

TX eCity TX4
Height 1890mm 1830mm
Length 4860mm 4580mm
Width (including mirrors) 2030mm 2030mm
Kerb weight 2,230kg 1,975kg
Electric range 80 miles 0 miles
Total range 377 miles 343 miles

Motor peak power 110kw / 148bhp (electric) 81kw / 109bhp (diesel)
Torque 255 Nm / 188 lbft 240 Nm / 177 lbft
Max speed 80 mph 80 mph
Battery 31kwh (23kwh useable charge) – 3 string lithium-ion 400V N/A
Accepted charging standards & speeds Vehicle works on 3kw, 7kw, 22kw, 43kw and 50kw chargers. Launch models have both CCS and CHAdEMO N/A
Range extender 1.5-litre petrol engine N/A
Combined fuel economy 217.3mpg (range extender only 36.7mpg) 33.2mpg
CO2 Emissions 29g/km (but only if range extender in use) 222g/km
NOx Emissions 1mg/km 44mg/km

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