Hydrogen-electric is the future, and the future is now. Forze Hydrogen Electric Racing wrote history this summer when it competed alongside conventional race cars in the Supercar Challenge race at TT Circuit Assen. The team’s hydrogen-electric-powered Forze VIII race car became the first to compete against internal combustion-engined cars and reach the finish in a 60-minute race.
From Forze Hydrogen Electric Racing’s first hydrogen-electric-powered kart eleven years ago, to a Nürburgring record-breaking time attacker, the students’ team from the world-renowned Delft University of Technology in the Netherlands arrived this summer at TT Circuit Assen to try and measure its newest LMP3-based, fuel cell-powered Forze VIII to the internal combustion machinery of the Supercar Challenge to promote a better, cleaner future of the automobile.
In recent years, batteries have become commonplace in road cars. With the Toyota Prius and Volskwagen Golf GTE as prime examples of electric-internal combustion hybrids, to full-electric cars such as the Tesla Model S, electric is making headway in becoming the standard for road cars.
But there are more ways to drive electric: the second decade of this century saw several of the world’s big car manufacturers bring their own hydrogen-electric cars into mass-production. As a host of hydrogen fuel pumps are planned to open in the Netherlands in the coming years—solidifying the nation as one of the world’s leaders in hydrogen technology—the sometimes scarily futuristic-looking technology, however, has yet to find a place in the public consciousness.
That’s where Forze Hydrogen Electric Racing comes in.
“The mission of our team is to promote hydrogen by building a hydrogen-electric race car and race it in the Supercar Challenge amidst internal combustion-engined cars to prove we’re capable of competing with a car that runs on a sustainable energy source,” Lode De Herdt, Forze Hydrogen Electric Racing’s Chief Powertrain and responsible for the electronic side of the Forze VIII, explains.
“It’s actually an electric car, but instead of batteries, we use hydrogen as energy carrier.”
When it comes to power output, the Forze VIII delivers a decent amount: the Ballard FC Velocity MK1100 fuel cell’s usual output of 110kW is equal to that of the average road car—only without any poisonous exhaust gasses caused by the burning of gasoline.
“We have a fuel cell that produces 110kW of power—or 148 hp—which is not a lot for a race car,” De Herdt continues.
“But we have another trick up our sleeve: a buffer made of supercapacitors in which we can store energy.
“At the entrance to corners, we brake regenerative, rather than mechanical, meaning we use the electric motors as generators to slow down the car. This generates energy which is stored in the buffers. Then, at the exit of corners, we have the energy from the fuel cell, plus the extra power from the buffers. We can choose how much of that energy is used. This is a part of the tactics of how quickly we want to exhaust the buffers.”
Converting the energy into movement are two YASA P400 electric motors placed at the rear-centre of the car on the rear axle. A self-designed planetary gearing system (1:4.6 ratio) weighing in at only 6 kilogram, serves as the car’s transmission.
“The engines each deliver 100kW continuously and 160kW in peak power. In total we now drive with 190kW of power. In theory it would be possible to drive with 320kW—the limit of our engines—for a very short time, but in reality we never do this as our boost would be very short and inefficient. 220kW is more of a realistic limit.”
Controlling the flow of hydrogen and oxygen is a system built in-house by Forze. In power engineering terms this is called the ‘Balance of Plant’. From the hydrogen tanks, a custom-made valve system transports the hydrogen to the fuel cell, hidden underneath a forest of wires and systems at the heart of the vehicle. In the fuel cell, the hydrogen is mixed with a highly regulated mixture of air, added via an electrically-driven air compressor capable of pumping 5,000 litres of air per minute.
“The car has two hydrogen tanks which are pressurised at 700 bar. Hydrogen is pumped into the fuel cell where it’s mixed with the oxygen in the air, which creates water. The hydrogen, or H2, and the O2 in the air form H2O: water.
“The water exits via the exhaust and as a byproduct we have electricity which is used to power the two electric motors on the rear wheels.”
Along with the powertrain and auxiliary systems, much of the chassis has been custom-made by the team itself as well. Based around the LMP3-spec ADESS-03, the original car has been stripped down to its monocoque and rebuilt to fit the Forze VIII’s needs. Without a gearbox and engine to carry much of the load on the rear of the car, a subframe has been added to contain the fuel cell and its systems. Altogether, the car weighs a total of 1,100 kilogram.
Keeping the car firmly planted on the tarmac is a double wishbone pushrod suspension configuration. The suspension is another element designed by Forze Hydrogen Electric Racing, utilizing Koni dampers to absorb the brunt of the forces when the car’s at speed.
Not to be outdone by any other modern LMP car, the Forze’s bodywork is made of carbon fibre reinforced polymer. To fit all the car’s systems and especially the tank into the pink machine, the team had to redesign the car’s aerodynamics and bodywork.
“We put a lot of work into this. The bodywork was designed by ourselves with the help of CFD simulations. With help from Jules Dock we created the molds and at Airborne we vacuum infused the layers of carbon fibre with resin onto the molds.
“After some finishing touches we applied the various panels.
“All of this cost us a lot of time up to the point where part of the team started working nightshifts to finish everything in time for the design reveal at our new main sponsor BWT’s paddock stand at 24 Hours of the Nürburgring.”
Although a fuel cell is much more efficient than an internal combustion engine, it still produces a fair amount of waste heat. To combat overheating, a water-cooling system similar to what is used in the FIA Formula E Series consisting of two large radiators, as well as aerodynamics designed specifically to feed the radiators the right amount of air, brings sufficient cooling. A total of seven different liquid cooling cycles provide cooling to different systems, each with its own type of coolant and temperature range.
The hydrogen tanks store a total of 5 kilogram of pressurised hydrogen gas—the second lightest substance in the universe. Both tanks are also found in the Toyota Mirai. The Forze VIII places the shorter tank alongside the driver in the cockpit and the longer tank horizontally in the back over the fuel cell. These Type 4 tanks are pressurised at 700 bar.
To ensure the hydrogen gas poses no danger in the event of an accident, high standards of safety measures are centered around the tanks. Contrary to popular belief, hydrogen-electric vehicles are as safe as conventional gasoline cars.
“Many people think that pressurised hydrogen in a car is a bomb—that’s incorrect. We don’t make the tanks ourselves, they’re bought. They must be certified and are recertified every couple of years by Kiwa. That means it’s all approved and well-controlled.
“The tanks are extremely strong: they’re made of polymer liners surrounded by carbon fibre. It’s all thoroughly tested by the manufacturer.”
As prescribed by ISO/TS 15869:2009, the hydrogen tanks are capable of handling up to and over twice their advertised pressure, survive open fires and can take high caliber gunshots without exploding.
“If the car crashes, the last thing that survives is the fuel tank—it really won’t break,” De Herdt explains.
“In the rare event that it does break, there won’t immediately be an explosion. Inside the tank there’s only hydrogen—for fire to occur you also need oxygen and that won’t get inside because of the high pressure inside the tank. It’s under so much pressure it’ll just spurt out if there’s a rupture. In the worst-case scenario, if a tank does burst open, all you get is a jet flame.
“Also, you need to keep in mind that a car with gasoline isn’t 100-percent safe either: when gasoline catches fire, it’ll keep burning on the ground. Hydrogen, because it’s under so much pressure and because it’s so light, it’ll quickly dissipate—even a jet flame is very unlikely to happen.”
Back on the race track, Forze Hydrogen Electric Racing wrote history when on Saturday the Forze VIII finished the one-hour long Supercar Challenge race at TT Circuit Assen competing against internal combustion-engined cars. Race 2 on Sunday, then, should’ve been the day the team had dreamed they’d bring the fight to the competition: with only 50 minutes of racing scheduled, the car would’ve had enough fuel to go full-power for the full duration of the race.
That, unfortunately, never happened, and it wasn’t the car’s futuristic tech that failed them. A safety concern regarding an off-the-shelf suspension part meant the team had to forego what would’ve been its greatest achievement yet.
With the end of summer in sight and the new university semester starting soon, the fulltime team members make room for a new draft of students to take over the running of Forze Hydrogen Electric Racing.
“For the fulltimers of this year it’s over,” says De Herdt.
“We leave at the end of August and then it’s up to a new fulltime team. After this event we clean up and transfer our knowledge to the new team-members. Most fulltime team-members will probably stay involved by giving advice and helping out.
“In a couple of weeks, I’ll start my master—like most fulltimers.”
Will be continued in 2019, and beyond.