UPDATE: It would be interesting and useful to see more independent testing of the fuel economy of the turbine/hybrid hummer. A 60 mpg hummer would need to have power sources that are about three times more efficient than a Toyota Prius which also gets about 60mpg. However, the Toyota Prius is about half of the weight at 2700lbs versus the Hummer at 4700lbs. Plus the Prius has 0.26 drag co-efficient while the Hummer has a drag coefficient of 0.5 to 0.57. About 60% of the power required to cruise at highway speeds is taken up overcoming air drag, and this increases very quickly at high speed. Perhaps the higher mpg figure is because the hydrogen that is added is not included in the calculation. It takes power to produce hydrogen.
However, the claims of getting one of the less fuel efficient models from 9mpg to 18mpg is more plausible. The Hummer H3 is rated at 16 mpg in the city cycle with both transmissions and 19 mpg (US) (14.7 L/100km) with the automatic or 20 mpg (US) (11.7 L/100km) with the manual on the highway. Increasing efficiency to the 32mpg range seems possible with an efficient diesel conversion.
Perhaps more fuel efficiency is coming from efficiently charging a smaller number and lighter batteries and capacitors for the electrical drive with a while driving basis with the turbine.
Like most hybrids, it'll have two engines, including an electric motor. But in this case, the second will be the turbine, Goodwin's secret ingredient. A 1985-issue turbine engine originally designed for the military. It can spin at a blistering 60,000 rpm and burn almost any fuel. And Goodwin has some startling plans for this esoteric piece of hardware: He's going to use it to create the most fuel-efficient Hummer in history. He charges $28,000 for a "basic H2 conversion to diesel--custom concept cars cost far more. Whenever the truck's juice runs low, the turbine will roar into action for a few seconds, powering a generator with such gusto that it'll recharge a set of "supercapacitor" batteries in seconds. This means the H3's electric motor will be able to perform awesome feats of acceleration and power over and over again, like a Prius on steroids. What's more, the turbine will burn biodiesel, a renewable fuel with much lower emissions than normal diesel; a hydrogen-injection system will then cut those low emissions in half. And when it's time to fill the tank, he'll be able to just pull up to the back of a diner and dump in its excess french-fry grease--as he does with his many other Hummers. Oh, yeah, he adds, the horsepower will double--from 300 to 600.
In the corner of his office sits Arnold Schwarzenegger's 1987 Jeep Wagoneer, which Goodwin is converting to biodiesel; soon, Neil Young will be shipping him a 1960 Lincoln Continental to transform into a biodiesel--electric hybrid.
His target for Young's car? One hundred miles per gallon.
The numbers are simple: With a $5,000 bolt-on kit he co-engineered--the poor man's version of a Goodwin conversion--he can immediately transform any diesel vehicle to burn 50% less fuel and produce 80% fewer emissions. On a full-size gas-guzzler, he figures the kit earns its money back in about a year--or, on a regular car, two--while hitting an emissions target from the outset that's more stringent than any regulation we're likely to see in our lifetime. "Johnathan's in a league of his own," says Martin Tobias, CEO of Imperium Renewables, the nation's largest producer of biodiesel. "Nobody out there is doing experiments like he is."
Goodwin installed the Duramax and a five-speed Allison--the required transmission for a Duramax, which also helps give it race-car-like control and a rapid take off. After five days' worth of work, the Hummer was getting about 18 mpg--double the factory 9 mpg--and twice the original horsepower. He drove it over to a local restaurant and mooched some discarded oil from its deep fryer, strained the oil through a pair of jeans, and poured it into the engine. It ran perfectly.
But Goodwin wanted more. While researching alternative fuels, he learned about the work of Uli Kruger, a German who has spent decades in Australia exploring techniques for blending fuels that normally don't mix. One of Kruger's systems induces hydrogen into the air intake of a diesel engine, producing a cascade of emissions-reducing and mileage-boosting effects. The hydrogen, ignited by the diesel combustion, burns extremely clean, producing only water as a by-product. It also displaces up to 50% of the diesel needed to fuel the car, effectively doubling the diesel's mileage and cutting emissions by at least half. Better yet, the water produced from the hydrogen combustion cools down the engine, so the diesel combustion generates fewer particulates--and thus fewer nitrogen-oxide emissions.