Could this new electric vehicle spark mass production in Scotland for the first time in decades? Jon Lawson finds out.
November 2023 proved to be an exciting month for Ross Crompton, Head of Design at Munro Vehicles, as a major milestone was achieved when the first pre-production vehicle rolled out of the company’s Glasgow factory. Named after Scotland’s iconic hills, the company has only been in existence since 2019.
“The founder’s original plan was to electrify an old Land Rover for adventures off-road,” Compton explains. “However, they soon found that after speaking to suppliers there is a niche in the market for a purely electric, rugged 4x4. As further research was undertaken, many companies said a vehicle like that would be very beneficial.”
One of the first decisions to be made was not to include a range extender generator. Compton continues, “These firms were interested from the outset in decarbonising, they made that point clear. The team at Munro has spoken to hundreds of companies to gain an insight into precisely what duty cycles their vehicles do. With the appropriate battery pack specified, operators can run for 19 hours which suits the work pattern they need. They are not looking for continuous use. Users likely need two days work on a single charge before returning the vehicle to base to be recharged overnight.”
TIME FOR DESIGN
Once the decision has been made to launch a new vehicle, design work started in earnest. “Being a working vehicle, we started out with the assumption that we would need space to comfortably seat five work men or women with all their gear, and enough room for cargo as well,” says Compton. “This gave us the base dimensions for the cabin and wheelbase. From there, we looked at approach and departure angles to size the body. The width is defined by UK agriculture, the fact it has to fit through a standard gate. Once this was sketched out on paper, we were able to work out how tall it has to be to give the occupants a comfortable space. This was then paired with all our in-house manufacturing processes (such as the press brake) – we weren’t interested in pursuing voluptuous curves. Manufacturing the body is about pressing and folding.”
Armed with this information, the design started to really take shape. “This is how we built the first two prototypes,” he confirms. “Only then did we start the modelling process, by bringing in a specialist who used to work for McLaren. He ran a bunch of simulations for us in terms of aerodynamics, which heavily influenced what we did going forward to the Series-M. This is particularly true of the front-end, where we removed a lot of panelling. We altered the design to create an aero channel, directing air into the wheel well which helps cool the brakes and directing it around the A-pillar which dramatically reduced wind noise.
“As well as a general improvement in aerodynamics, there were other ramifications including for the windscreen washers: we have been able to improve how they work based on how the air moves over the body at speed.”
Other improvements quickly followed. “By creating that space and allowing more air through the front, cooling is much better,” he adds. “What’s more, we have been able to create a single stack under the bonnet to house all the critical componentry. This made maintenance infinitely easier, which is exactly what we are keen to do.”
The battery system is the heart of any EV, but why choose lithium iron phosphate (LFP)? Compton says, “There’s a handful of reasons for this. Firstly, it can be fully charged up to 100%, and with no nickel or cobalt it’s more environmentally sustainable. Also production costs are lower, and from a safety perspective, in the unlikely event that there is a puncture to one of the packs, the chances of thermal runaway are reduced.”
Mindful of moisture, he adds, “Three battery enclosures are mounted alongside the chassis rails. The enclosure lid and electrical connections are completely sealed against external ingress. Sensors alert the operator in the unlikely event of damage leading to water ingress.”
The choice of motor is also interesting, Compton explains, “We use a permanent magnet axial flux motor. It’s a very new technology that larger OEMs would not use. It offers us the ability to have an even weight distribution, and is in keeping with our philosophy of working closely with suppliers to develop these new ideas together.”
For suspension, inspiration came not from industrial vehicles but from the rally world, with heavy duty springs designed for high impact, high wear environments. Where components in the drivetrain have been selected off-the-shelf, the highest specification has been ordered.
Instead of built-in obsolescence, it is designed out from the start. “We expect these vehicles to last at least 50 years,” notes Compton. “They are expensive, and in order to make them a good investment they must be upgradable over time. At some point battery technology will improve, so you unbolt the old ones and replace them. Motors, axles, everything is designed to be easy to swap in and out.”
The testing process is being overseen by a British off-road driving association (BORDA) and Lantra-qualified off-road driving instructor who has built his own test track, a logical development bearing in mind where these vehicles will likely end up. “We partnered with him right from the first prototype,” Compton adds. “His instructions are to use the vehicle to try and break things so we can find out stress points or points that need reinforcing, as well as give us a general sense of how capable it is off-road. We also record a lot of data, heat generated, torque produced, etc. Throughout 2024, we intend to go much more in-depth, and include cold weather testing in Scandinavia.”
Compton is also interested in other real world performance figures. For example, what will towing do to battery life? He says, “To accelerate the testing phase, we are partnering with early adopters who have put in orders. We are supplying them a vehicle to use and in return we can get large amounts of live test data. We are keen to work with companies directly so we can really understand exactly what happens under these workloads.”
The vehicle’s manners on-road are also currently coming under scrutiny. “We’ve got this amazing off-road vehicle, so how can we start injecting comfort without compromising this ability? We’re now working on things like sound insulation and fine tuning the suspension.”
The design will be further optimised in the early part of the year, with a plan to produce the first 50 trucks by the middle of the year. A new factory is on the horizon, and by 2027 Munro expects to sell 2,500 vehicles annually.