I posted this picture of the GreenGT H2 on the Flux Auto Facebook page and got a question about the details of the car and how hydrogen fuel cells work. This post will address all of those things. Lets start with the car. The H2 is made by a French vehicle R&D company called GreenGT. It will be racing in the 24 hours of Le Mans next year in the Garage 56 experimental car exhibition spot that was occupied by the Nissan DeltaWing this year. The chassis of the car is made by Welter Racing and their are two electric motors that produce 540 horsepower to drive the wheels to a top speed of 186 mph. The interesting part H2 comes from the energy storage system. The orange tanks on the side of the car hold enough hydrogen gas to power the car for 40 minutes at a time. The H2 has a high temperature Proton Exchange Membrane Fuel Cell (PEMFC) that produces 340 kw. To be more specific, the car carries 18 combined cells that produce 20 kw each with one functioning as a backup. The science behind fuel cells is that a semi-permeable membrane separates hydrogen gas and oxygen. This membrane only allows protons to pass through it. What happens is the electrons and the protons from the hydrogen gas split up. The protons pass through the membrane and bond with the oxygen to form water. The electrons travel down the membrane to be used as electrical energy. Here’s a video illustrating the chemistry:
The theory behind fuel cells is sound (i.e. they actually work), but practical implementation is still lacking. Currently they are only a little more efficient than combustion engines even though they come in a much bulkier package. Harvesting, transporting and storing hydrogen also presents it’s own set of problems. The general public tends to associate hydrogen with the Hindenburg and seem to think it’s an explosion hazard(the same was said about gasoline when we switched from steam powered cars). In reality, a hydrogen leak is actually safer than a gasoline leak. Hydrogen gas dissipates extremely quickly since the molecules are so light. You will lose the gas before it has a chance to detonate which is a lot safer than liquid gasoline pooling up under a leak. The quick dissipation of hydrogen gas is also what makes it difficult to store. Since it’s the smallest atom, it tends to find its way through other materials. Fuel Cells are a clean way of producing energy but face similar R&D barriers as the rest of the green industry.
I promise to make a post about the RX-8 I bought for the EV conversion soon. Until then the quick and dirty details are that I towed it home and it runs perfectly, so I’ve been driving it around and enjoying my first rotary powered car. It drives absolutely amazing which has piqued my interest in rotaries in general. This video has been the best explanation of how one works that I’ve found on YouTube:
When you’re talking rotaries, it doesn’t get much better than the Mazda 787B. It has a 4 rotor engine with variable length intakes mounted midship. The 787B was the first and still the only Japanese car to win the 24 hours of Le Mans. This video was taken at last year’s 24 hours of Le Mans to commemorate the 20th anniversary of the victory. Mazda got one of the original drivers to take the 787B around a full lap of the Circuit de la Sarthe.
I normally don’t like to post these Shakedown videos of the guys just sitting and chatting, but this one has a lot of interesting news that’s relevant to what we’re about here at Flux Auto. This episode revolves around the 2012 Le Mans 24 hour race that just finished up. Leo talks about how the Toyota TS030 and Audi E-Tron Quattro did as well as the future of the Nissan DeltaWing which was knocked out of the race by a driver who claimed he couldn’t see it in his mirrors. There’s also news about engine restrictions, energy consumption and hybrid drive trains for the race next year. The last part is an interesting bit of news regarding Mazda’s announcement that they were producing Skyactiv diesel engines for P2 cars next year as well. I’m glad to see that the movement to develop fuel efficient performance cars in racing is so strong. Racing breeds strong innovation.
Ride along with Tom Kristensen as he pilots the Audi R18 E-Tron Quattro for a night time qualifying lap for this year’s 24 hours of Le Mans. Two things of note: first is how crazy fast he’s going. Imagine having to concentrate hard enough to maintain that pace for hours at a time. Second, you can clearly hear the electric motors wind down the front wheel speed in the heavy braking zones. That energy is then stored by spinning up a magnetic flywheel that sits in the passenger seart. It’s the same system that Porsche has been running in their 911 GT3 RS Hybrid endurance car with a couple of upgrades. The flywheel housing is now carbon fiber to save weight. The housing’s job is to hold a vacuum so the flywheels can spin without air resistance which would have been significant at 40,000 rpm. The car in the video qualified fourth overall, but the other E-Tron Quattro was the first ever hybrid to take pole at Le Mans.
Road & Track put together this video that takes a closer look at the hybrid cars competing in this year’s 24 hours of Le Mans, the Audi E-Tron Ultra and Toyota TS030. They talk about how each car has different engines, energy storage and even electric motor power delivery.