Challenges for electric ambulances

Emergency transport has not been unaffected by the UK drive to decarbonise transport, finds Steve Banner

Ambulance fleets seeking to go zero-emission face particular challenges. Responding to an emergency could be difficult, if not impossible, if an electric ambulance’s batteries are being recharged, while crews are likely to face a particularly acute form of range anxiety if their vehicle has insufficient range to get to an incident. Their concern will be increased if, having reached a road crash, they do not have enough mileage left to get a severely injured casualty to hospital.

Range restrictions also affect the ability of a battery-electric ambulance to transport a critically-ill patient from one hospital to another at the far end of the country which might be one of the few that can provide the specialist treatment the individual may need.

Hydrogen powertrain specialist ULEMCo believes it has come up with the answer. It worked with Lyra Electronics and WN Vtech, which includes ambulance builder VCS (whose parent was bought out last month after entering administration: see news, p8). The result was a prototype ambulance with a hydrogen fuel cell range extender with an electric drive. It can cover up to 300 miles before it needs refuelling, says ULEMCo; and filling up with hydrogen is a lot quicker than replenishing a battery. The vehicle features a low-frame chassis with a low floor to make access to the interior easier for patients and crew members. Supported by government agency Innovate UK and NHS England, the ZERRO – Zero Emission Rapid Response Operations – ambulance project was originally started by Yorkshire Ambulance Service. The large area it has to cover means it needs the range that a fuel cell can provide, says ULEMCo.

The vehicle has been trialled by London Ambulance Service (LAS), which has already begun operating a number of zero- and low-emission vehicles. They include over 40 battery-electric Ford Mustang Mach-E cars.

Clearly they have neither the space nor the payload capacity for all the equipment that a Ford Transit or Mercedes-Benz Sprinter can accommodate. That is not what is required of them however, because they are ambulances used by FRU – Fast Response Unit – paramedics. With a 0-60mph acceleration time of around six seconds according to Ford, they can get to stroke or heart attack victims quickly; and rapid intervention is vital in both cases.

It takes 40 minutes to charge a Mach-E Mustang’s battery to 80% of its capacity, LAS says – which, though not unimpressive, is nowhere as quick as a hydrogen refill. It delivers a range of over 300 miles, says LAS, which is far more than is needed in London.

The vehicle’s blue lights and sirens are powered by a separate 12V battery, which highlights another challenge for ambulance operators. The electrical equipment their vehicles carry, including life-saving kit, usually requires auxiliary batteries, which add weight. LAS is dealing with this challenge by fitting solar panels.

LAS has also acquired 65 petrol-electric hybrid cars, a mixture of Volvo XC90s, XC60s and Ford Kugas. Fourteen of them are being used by advanced paramedics, and EPRR (emergency preparedness resilience and response) teams who treat patients at major incidents and in dangerous environments. The majority, however, are employed by clinical managers to get to incidents.

Says LAS head of fleet, Rob Macintosh: “Greener vehicles are vital for our staff and communities, and we’ve already invested £31m to introduce them, put in electric charging points, and recruit more mechanics.” Suitably trained technicians will be needed as LAS moves to a net-zero-emission fleet by 2030.

With this goal in mind, LAS is rolling out four battery-electric Ford E-Transit ambulances bodied by WAS, and with Ford’s involvement. The Emsburen, Germany-based ambulance builder has already supplied a number of electric ambulances to services in its own country using the Mercedes-Benz eSprinter as a platform.

Far bigger and heavier than LAS’s Mustangs, and designed to fulfil a different role, the box-bodied eSprinter-based WAS 500 E-RTW offers a range of up to 125 miles, says the company. That includes using the traction batteries to run the vehicle’s medical equipment as well as to power its heating and air-conditioning.


A key drawback from a UK viewpoint is the eSprinter-based ambulance’s 5.5-tonne gross weight. British drivers who obtained their car driving licence after 1 January 1997 have to take a separate test before they can get behind the wheel of anything grossing at above 3.5 tonnes.

The government has introduced a concession which allows all car licence holders to drive electric vehicles grossing at up to 4.25 tonnes. The aim is to compensate for the weight of the battery pack and enable fleets that want to go electric to achieve the same payload that they would be able to achieve in a diesel 3.5-tonner.

The concession would not benefit the WAS-bodied eSprinter, but it does benefit the e-Transit however, which grosses at a maximum 4.25 tonnes.

German customers for the WAS 500 E-RTW include Hanover Fire Brigade. (In some countries, fire brigades are responsible for the operation of all emergency vehicles, including ambulances as well as fire appliances.)

Aside from zero exhaust emissions, advantages of going electric, WAS says, include strong acceleration, good road holding thanks to a low centre of gravity created by the positioning of the batteries in the chassis frame, reduced maintenance costs and low interior noise levels. A lack of exterior noise thanks to the absence of a diesel engine on tick-over is a benefit if the ambulance is stationary at an incident.

But range and charging times remain a concern. Says Hanover fire chief Christoph Bahlmann: “All idle times must be used for charging if possible, and patient handover times at hospitals are ideal for quickly charging the drive batteries.”

All of the casualty departments in Hanover were equipped with charging points before the new ambulance was put into service. They are not necessarily in place at NHS hospitals.

Elsewhere, Ford and ambulance builder Venari Group have developed an ambulance on a Transit platform under the Project Siren banner. It grosses at below 3.5 tonnes so that it can be driven by anybody with a car licence. Holding its weight down has involved extensive use of composite materials in the body plus measures such as fitting a thinner, lighter windscreen and alloy wheels.

However, plans to produce the newcomer at Ford’s Dagenham site, which would create 100 jobs, were due to bear fruit in 2022, but have yet to be implemented.


Ambulance builder Venari has been busying itself with the production of much heavier vehicles. At its plants in Goole and Brighouse in Yorkshire, in 2022 it began converting dozens of ex-British Army vehicles into armoured ambulances destined for Ukraine. With an all-terrain capability, they are designed to protect crews and patients from small arms fire. Displaying the Red Cross is no guarantee of immunity from Russian bullets.

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