Jaguar's Hybrid Jet-Powered Concept Car 334
An anonymous reader writes "Jaguar has developed a hybrid car that runs on gas turbines. The range extended vehicle usually uses four electric motors (one on each wheel) plus a lithium-ion battery pack for propulsion, but can achieve a performance boost from a pair of gas turbines mounted in the rear. Cnet UK reports the car can do 0-60 mph in 3.4 sec. (and 50-90 mph in 2.3 sec.) and reach 205 mph while emitting less CO2 than a Toyota Prius."
Should be reliable (Score:5, Interesting)
I'm a little suspicious of the emission claims though. How much of that is from plugin? I can't imagine turbine->electric->battery->motors is an efficient drive train.
Re:A step in a right direction (Score:5, Interesting)
It's funny how developments that reduce the environmental impact of cars often originate from the high-performance end of the spectrum. While I'm no expert, my understanding is that sports such as Formula 1 and Indycar have done massive amounts to improve the fuel efficiency of the cars you see on the roads every day. After all, there's a clear and direct incentive when you have a high performance car out on the track to design something that can carry a smaller (and lighter) fuel tank or get away with fewer refuelling stops. And once you've developed that technology, you might as well make good use of it on a commercial basis.
Agreed (Score:3, Interesting)
Re:Should be reliable (Score:5, Interesting)
It did have two major disadvantages - unreliability due to brittleness of the heat exchanger, and
- the tendency to singe the paint off cars that approached too close to the exhaust.
"I shit the bed" (Score:3, Interesting)
Gas turbines are powerful for their weight, but not exactly economical in fuel use.
A friend of mine was a tank commander in the US army. He complained about the reliability of the gas turbine engines in the M1 Abrams tanks. When they break down, oil gets into the turbine, and spews itself around.
Over the radio, when your tank breaks down, you say, "I shit the bed."
On the other hand, he was really impressed with the German Leopard tank. It just uses a turbo diesel engine, so it is not so sexy, but seems to get the job done.
The problem with safety systems like that (Score:5, Interesting)
...tends to be that by definition, they only kick in when something is broken.
I used to climb a little bit. We'd be up on a thousand feet of exposure with just a thin nylon harness and some carefully tied rope. Now I'm a firefighter and have done some rope rescue classes. We don't even go on a steep hill without a far more complex (and heavy) harness system. It seemed ridiculous to me, but it was explained that if the usual way of doing things had worked then we wouldn't have been called in. Something has gone wrong, and we can't always know what it was.
The same problem exists, to us, for cars like the Prius. Lots of very high voltage cables running through parts of the car we would usually cut through to get someone out. In theory, there are safety systems that will cut power to those cables after an accident. In practice, what if the accident affected those cut-off systems? There's a manual cut-off -- I'd have to check the reference material we have, but I think it's under the back seat. If I could get to something under the back seat, I wouldn't need to cut the car apart.
When things are broken, they're ...well....broken. The safety systems may or may not be affected. I think the issue in this case is that broken at 65 miles per hour is one thing, and broken at 205 miles per hour is something else entirely.
I think if a car that was moving that fast being propelled by four independent motors suddenly found itself being propelled by thrust that was no longer balanced and centered -- I wouldn't want to be down range for quite some distance.
Re:Other turbine-powered cars (Score:3, Interesting)
I remember hearing about some of the problems with this, and another. A turbine also happens to be wonderful gyroscope, so Chrysler's Turbine Car (I remember seeing the TV commercials as a kid.) had an embedded gyroscope which interfered somewhat with steering. Obviously arranging the axis of the turbine correctly can take care of this, but might make it more difficult to extract power from the engine. When I heard that this new car had 2 turbines, especially after reading about the difficulty of scaling turbines downward, I thought "counter-rotating" to mitigate the gyroscopic effects.
I also have an old high-school friend that has the gearbox problem. He travels to tractor-pull competitions with his jet-powered tractor. Last I talked to him, his #1 maintenance item was the gearbox. No matter what you did, high power plus high RPMs just makes for a tough problem. I also saw the engine room of the battleship Massachusetts at Fall River, Ma. It was steam turbine powered, and the gearbox was several times the size of the turbine.
Using the turbine to drive a generator instead of trying to directly extract mechanical power out of it solves a lot of problems. But from some other reading, I get the impression that they still gear the turbines down, preferring to generate electricity at about 1800 rpm instead of the direct 30-40 krpm. Makes me wonder about the difficulties of high-rpm electrical generation, and how tough that would be to solve.
Re:Other turbine-powered cars (Score:3, Interesting)
Rather than complex rules.. (Score:4, Interesting)
I've always thought that NASCAR in particular could reduce the thickness of their rulebook considerably by putting the teams on a fuel allowance for the race. If the cars start going too fast to be safe, pull back the fuel they are allowed to get.
Re:The problem with safety systems like that (Score:2, Interesting)
No. Why would we?
One of the key components to any fire department is mutual aid - we help each other out. We do similar things with external entities. I need high voltage cut off? I call the power company. I know of no specialized "high voltage" unit or response team in any FD anywhere in the world, save for some industrial fire departments working at large power generation facilities.
We will strip a meter out of a box as a last resort, but we prefer letting the power company handle it. They're trained for it, they have the equipment (which they know how to inspect properly), etc. If we have an electrical hazard, we make a risk/reward decision and try to work around it. If the structure is fully involved and we either know everyone has been evacuated (per the homeowner) or we see that the conditions are not compatible with life, then we won't take a big chance. If we know there are three kids trapped in a bedroom, we'll work around the hazard as best we can to effect the rescue. Firefighting is a series of these decisions - is the amount of potential "good" worth a given amount of peril to my life and the lives of my crew?
Now, think about a crunched-up car, especially a little microbox like a Prius. The guys who work on HV for a living don't have "suits" - they have proper clothing, long insulating gloves, insulating boots, etc., along with tools that do their best to keep them away from the high voltage where possible. Ever tried a set of lineman's gloves on? You can forget any fine motor control. Now, think about what happens when you have no fine motor control and you need to mount an effective rescue on a car that's been crunched badly, while people sit inside bleeding to death. As it is, we are issued additional equipment for vehicle extrication and wildland firefighting (dual certified gear) - jumpsuit, gloves, lightweight helmet. The typical structural firefighting PPE is simply too big and bulky, and it impairs movement to the point that working with hand tools, rescue tools, etc. becomes very difficult. Lineman's gear would be even more of a problem.
Plus, how much gear do you carry? As it is, for my personal gear (this is what's in my locker, not counting what lives on the apparatus), I have:
Full set of structural PPE (coat, pants, suspenders, boots, helmet with light/band/wedges, 2 pairs of gloves, medical gloves, hand tools, rope bag, search loop, additional flashlight, etc.)
Full set of extrication/wildland PPE (jumpsuit, gloves, helmet, hand tools, flashlight, medical gloves, rope bag)
Handheld radio, another flashlight or two, more tools, etc.
I carry all of this every time we get a call (about 700 calls a year, I average 50-60%, all volunteer). Add too much more and we'll need a second truck to carry all of the gear!
Re:The problem with safety systems like that (Score:3, Interesting)
I don't know what voltage you have in a Prius, but I'm an electrical engineer and I'm pretty certain that any sort of rubber gloves, even those very thin ones worn by surgeons, will keep you safe from the voltages found in an electric car.