When John Q. Everyman thinks of a hybrid car, odds are he's picturing something like a Prius or an Insight. It's true that gasoline-electric hybrid systems are the powertrain of choice right now, but what of diesel-hydraulic hybrids?
It's not the most obvious solution to energy storage, but already a number of experimenters and low-volume manufacters are starting to toy with the idea of using tanks of pressurised fluid to store energy instead of a battery. Lightning Hybrids is one of them.
The idea does have merit: there's no disposal hazard as there is with batteries, the lifespan of the system would likely be longer than that of a hybrid's battery pack and the entire system is slightly less complex.
Lightning Hybrids is one outfit that's working with hydraulic hybrid technology and it recently exhibited its LH4 diesel-hydraulic hybrid concept at the Denver Auto Show.
The LH4 is Lightning Hybrid's entrant for the long-running Automotive X Prize, a competition whose sole goal is to find the world's first genuine 100mpg vehicle (that's 2.35l/100km to us Australians).
The LH4 combines a front-mounted three cylinder biodiesel-fueled Volkswagen engine with a powerful hydraulic pump/motor in the rear, which is hooked up to a low-pressure and a high-pressure oil tank. Lightning Motors says it'll do 100mpg easily, and will cost between $39,000-59,000 USD ($54,800-82900 AUD) when it goes on sale in 2011.
It's a good idea and one that hopefully can provide some real-world results, but hopefully by 2011 they'll have ditched that hideously impractical (and, well, just plain hideous) motorised cabin shell (below).