Dr. Greg Offer & Aaron Kankiwala, Imperial Racing Green
Helen - Electric and hybrid cars do have a bit of an image problem. Many people think they're a bit slow, a bit goody, goody, perhaps a bit worthy, but this week, Meera Senthilingam visited Imperial College London to find out how electric and hybrid cars could soon rival modern petrol hungry muscle cars.
Meera - This week, I've come to Imperial College London to meet the scientists and engineers of Imperial Racing Green. A project that designs electric and fuel cell hybrid cars for the race track. And with me is Dr. Greg Offer, the Academic Project Manager. Now Greg, firstly, what are electric and hybrid vehicles? How do they work?
Greg - An electric car is powered by batteries. The batteries need to be charged by electricity which you take from the grids. Every building in this country has a power socket and you can charge the batteries from the power socket. The batteries then power an electric motor which drives the wheels. The main problem with this is actually the amount of power you can get from the socket. Most domestic circuits are limited to 13 amps. So, it will take you quite a few hours to charge your battery.
Meera - And how about the hybrid car?
Greg - There are two types of hybrids. The first is what I would call a first generation hybrid which is like a Toyota Prius. That’s an internal combustion engine powered vehicle which has an electric motor and a small battery pack to assist the combustion engine. Second generation hybrids are the more interesting. This is an electric vehicle which is a battery powering, electric motor powering the wheels. And it then has an internal combustion engine, arranged extender to assist the electric vehicle when it’s needed. But you can still run it as an electric vehicle.
Meera - Now why would an electric vehicle need assisting?
Greg - The main Achilles’ heel of electric vehicles nowadays is the batteries and to deliver the range that consumers are used to, you have to have a lot of batteries which means expensive weight and size. So, in order to overcome some of those problems, we used a range extender.
Meera - Now, what are the advantages then of these hybrid and electric vehicles over an internal combustion engine vehicle?
Greg - Okay. The principal advantage of the battery electric vehicle is the efficiency. Even now, with the way that we currently generate our electricity in this country which is predominantly through coal and gas burning off, the electric vehicle is still going to produce roughly 50% less CO2 emissions per mile.
Meera - Are there any advantages of the actual performance of the vehicles?
Greg - Yes. Electric vehicles will perform better in terms of acceleration. The electric motor is much more efficient at low revs. In fact, you get all of your power from standing which enables you to accelerate from the line much quicker and combustion engines are remarkably inefficient and don't give you much power when you're accelerating. There’s also some other advantages in terms of air quality. Combustion engines produce other emissions in addition to CO2 such as nitrous and sulfurous oxides and those are currently governed by some quite strict regulations which we’re getting stricter and stricter. Electric vehicles don't produce any harmful emissions from the vehicle.
Meera - What do you think then the future of these types of vehicles are? Are we likely to see electric vehicles being used by everyone soon?
Greg - Pretty much, every new car on the road within 10 years, I predict will be electric in some form or another. And by 2030, they’ll all be plugged in hybrids. And then once we get to 2030, we’ve probably met our emissions reduction targets. We need to reduce CO2 emissions by about 50% by 2030. We can do that with plug in hybrids. The question is now, it’s about scaling up. It’s about mass production and actually requires a lot of people. So, training engineers is crucial and this is what Racing Green is all about. We train over a hundred engineers a year in electric and hybrid vehicle technologies. They can then go and work in these industries and actually become the engineers who help us build the future.
Meera - Dr. Greg Offer, the Academic Project Manager here at Racing Green. Now, he mentioned that they're training up the engineers of the future and I have one of these engineers with me now and that’s Aaron Kankiwala who’s the Chief Power Train Engineer for Racing Green. So tell me what you're doing with Racing Green? Because you're actually adapting this electric vehicle technology in hybrid technology to make race cars.
Aaron - Yes, very much so. Part of the stigma about green cars at the moment is that they're not very sexy, not very quick. So, what we’re doing is taking this technology and putting it on the race track. We’re actually standing next to our current vehicle here, which is a third we’ve built. The previous two being go-cart sized vehicles and now, this is our four-wheel open racer. It’s about 1.5 meters wide by 3.5 long. Fairly sizable which will enter into the Formula Student championships in July. Formula Student has been around for a long time, a competition run by the Institute of Mechanical Engineers. It’s predominantly IC engine cars, showcasing student’s skills and building these types of vehicles. For the last two years though, they’ve allowed entries in a low carbon class and that’s what we’ll be entering into with our zero carbon vehicle.
Meera - What have you had to do with this to adapt General Electric vehicle and hybrid technology to make it into a race car.
Aaron - Well, one of the biggest problems we’ve had was weight. Race cars need to be very light, so they handle well and are very nippy around the track. Unfortunately, electronic components at the moment aren't built for race conditions. Most of the components we use on the vehicle actually meant to sort of stand still in a laboratory and power sort of a generator for awhile. Yet, we’re taking this technology off the shelf and making it perform around the track. And so, we’ve tried just like the most lightweight components we can, giving us the best powerful rate ratio on the vehicle.
Meera - So what are the advantages of using an electric vehicle over an internal combustion vehicle on a race track?
Aaron - Electric motors actually have a distinct advantage over IC engine cars because they can produce their full torque from zero revs. Another advantage is the ability to use regenerative breaking. When an IC engine car breaks, a lot of energy is wasted in just heating up the disc breaks. Whereas we, can actually restore this energy that we’ve put down on the track, back into our batteries and go further, faster, longer.
Meera - Now, this particular model is an electric car but it uses a hydrogen fuel cell as well?
Aaron - Yes. The primary use of the fuel cell on this vehicle is to produce active power and also, to extend the range of the batteries that we’re using as well. With the fuel cell running throughout the whole race, we can actually go about a third more distance which means we can go a third faster. It’s very usual and a very neat solution to overcoming the range problems that come with batteries and electric vehicles at the moment.
Meera - So have you had a go? Have you had a test? How fast did it go?
Aaron - It’s geared up now to do 75 miles an hour, top speed. That’s because we’re going round a fairly, twisty, turny track. If we geared it to its full potential, it would be topping 300 miles an hour.
Meera - That’s impressive.
Aaron - Yes, impressive. Not feasible for that race track but it shows that this technology can do some fairly impressive stuff.