Horses For Courses Or Why We Need Both Battery And Fuel Cell Powered Vehicles

Horses for courses is a British expression. It comes from the fact that some horses perform well on certain racecourses but not so well on others, and vice versa. Today the expression is used as shorthand for any situation where there is no one-size-fits-all solution. Take clothing: swimwear is good for the beach; suits are more suitable for an interview. We believe the same is true for fuel cells and batteries. These two technologies are often described as competing. But we think they should be seen as complementary. We need both to deliver the dramatic reduction in carbon emissions necessary to avoid catastrophic climate change. This article sets out why.

Let us start with batteries, or the vehicles those batteries sit in, battery electric vehicles (BEV). BEVs are starting to become mainstream, which is great. And for good reason. Setting aside the environmental benefits, if you need a car-sized vehicle, to mostly do short trips and have access to a charging point, then a BEV is the best solution. There is no question about it. Even if you need to do the infrequent long journey, you can make it work with forward planning. Few will mind stopping for a coffee and a charge-up en-route to your destination on those rare occasions when it is required; a time for you and the car to re-energise. In our view, BEVs are going to get cheaper, faster than most predict. We see them dominating the passenger car market in relatively short order.

But what if you are one of those people who frequently make long journeys, perhaps often doing A to B to C routes all over the country. Then a BEV might not be so convenient, especially if you can’t find a high-capacity charge point on your route. And what if we look more broadly, to long distance travel and the transportation of goods as well as humans. Goods are transported around the world by ship, plane, train and truck, which all need some form of viable propulsion in a net zero world. For this short article we will just look at one use case: on-road goods haulage.

Take a medium-sized van such as a Mercedes Sprinter. The incumbent diesel version weighs 2 tonnes with a 1.5 tonne carrying capacity (3.5 tonne gross weight). This matches neatly with regulations in Europe: anyone with a driving licence can drive a van with a gross weight of 3.5 tonnes or below. Above that there are additional training/ licence requirements. Mercedes has introduced a BEV version of this van, the e-sprinter. It weighs 2.8 tonnes. Which, for the same overall gross weight (so that anyone can drive it) has a ~700kg load-carrying capacity. Why is the load carrying capacity halved for the BEV compared with the ‘conventional’ vehicle? The 55kWh battery, that provides the vehicle’s 95-mile range (according to the Worldwide Harmonised Light Vehicle Test Procedure or WLTP), is quite heavy. Now this van could be perfect, say for delivering online orders around a town. 95 miles is enough range and the vehicle can be charged overnight back at base. But what if the vehicle is used to take large amounts of goods long distances across the country? Well, then a fuel cell could be useful to bring into the mix.

Before we explain why, we should consider the other element that we need to grapple with for any zero-emissions vehicle propulsion system: the re-fuelling/charging infrastructure.

En-route rapid chargers for BEVs can get very power hungry for bigger/longer-distance vehicles (into megawatts) which has serious implications for the electricity grid. And you can’t always simply time-shift charging to overcome that. Charging the vehicle ‘at home’ at night isn’t an option for these applications in the way that it often is for passenger cars or ‘back to base’ operations. Further, en-route charging leads to ‘downtime’; whilst the vehicle is being charged it is not doing its job of moving goods around. And if this downtime becomes an extended period, it can become a substantial business cost. In some cases, where every minute of operation counts, it can even be make or break.

"In our view, BEVs are going to get cheaper, faster than most predict. We see them dominating the passenger car market in relatively short order"

How do fuel cells, or the vehicles those fuel cells sit in (FCEVs), perform on these fronts? In very general terms FCEVs do well on, for example, range and rapid re-fuelling; hydrogen is a (gravimetrically) dense fuel, so provided you have the space to store it, you don’t need to worry about range nor downtime for refuelling. Forklift trucks for example often operate 24:7 in warehouses and here fuel cells have become commonplace owing to the value placed on avoided downtime.

You could rightly point out that another reason fuel cells work well for forklifts is because hydrogen can be provided on-site. That is true and of course in any fuel cell vehicle, hydrogen will need to be available. What is interesting to consider is the required density in each case of the refuelling infrastructure and the level required to reach critical mass. You need dramatically more electric charge points than hydrogen re-fuelling points to service the same fleet. 

What if you wanted to provide sufficient hydrogen infrastructure for just the routes that your business’ vehicles travel on? Yes, a bit more than the single point needed by the forklift trucks operating in a warehouse, but it’s not a crazy number. A few carefully placed re-fuelling points could comfortably cover the designated routes.

Ok, if you’re with me so far, you’re probably wondering why you’re not FCEVs rolled-out for these applications in the way you are seeing increasing deployments of BEVs? In short, fuel cells are too expensive. Or at least they have been. Why? Typical fuel cells are feats of complex engineering, requiring reactant distribution, temperature and water management and incredibly fine manufacturing tolerances; all code for expensive!

But not so for one of the horses in our stable. Bramble Energy is a company that span-out from Imperial College and University College London with a unique manufacturing route for hydrogen fuel cells that utilises the printed circuit board (PCB) industry. In this way, Bramble Energy leverages a high precision, mass manufacturing industry capable of producing hydrogen fuel cells at a fraction of the cost of existing fuel cells.

In addition, Bramble Energy’s fuel cells are form-factor configurable. Vehicle manufacturers can take advantage of this form factor flexibility and competitive cost to deliver viable fuel cell solutions for the first time. For more on Bramble Energy, see: www.brambleenergy.com

Bramble Energy is just one of the bets we have placed. Others include Ceres Power (fuel cells) and Dukosi (batteries), both of which have performed extremely well for us.

So, fuel cells or batteries? No, horses for courses.