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Hybrid: Understanding the Concept



The term “hybrid” as it applies to automobiles means that two systems are being integrated for motive force:

    1) A fuel burning, internal combustion (IC) engine,
        like any other vehicle, and
    2) An electric motor and battery bank.

It basically means combining a regular car and an electric one into a “hybrid". This is a very old idea; for example, the modern train locomotive has been diesel/electric “hybrid” for about 100 years now…

You will notice that the MPG ratings for the typical hybrid vehicles are OPPOSITE to regular vehicles. That is, the city rating is higher than the highway rating. This is true because in city driving—where there is a lot of stop and go—the internal combustion engine part of the propulsion system can be completely shut down, and no fuel is consumed. To inch forward in traffic, which takes very little power, you can use the electric motor and stored battery power, which was produced by the IC engine which burned fuel to make it. When you get moving on the open road, where lots of power is required to keep you moving at a high speed, the battery power is quickly depleted, and the IC engine kicks in full time. At that point, you are back to MPG similar to any highly efficient (like a TDI, for example), non-hybrid vehicle of the same size, weight, aerodynamic drag, and engine efficiency. Thus, hybrids are best suited for city folks, not long-haul vehicles. Since VW campers typically do not spend a great deal of time in stop and go traffic, the application of current, common hybrid technology would not be useful. That said, using newer technologies, the concept is theoretically applicable with some tweaking.

We did some preliminary research into the viability of the all-electric and/or hybrid approach in 2015. We found that the technology needed for an affordable conversion is just now becoming a reality for a company of our size to apply to the relatively small Vanagon market. In particular, there have been significant strides made in battery technology. That in turn has made it possible to produce viable all-electric vehicles. Indeed, Tesla makes only all electric vehicles. GM has a couple of models now, and other manufacturers are not far behind. There have even been some rumors that Audi will no longer offer any petroleum burning vehicles after 2020! In time there is no doubt that we will see fast-charge and battery swapping stations infrastructure taking shape soon.

 

With enough battery storage capacity, it is theoretically possible for a VW camper to be switched over to electric power, and then be able to take advantage of fast-charge stations, and maybe even battery change stations. But, it will probably take quite some time before batteries are so standardized that change stations will become a reality, let alone available to non-OEM applications. But in the shorter term, a long-haul design hybrid system might be just the ticket.

 

Current hybrid vehicles are really just regular piston-engine vehicles with electric motor and batteries added. These have an engine that can propel the vehicle perfectly fine and indefinitely even after the battery pack is completely depleted. A long-haul hybrid would be designed in the opposite way. That is, the long-haul hybrid would be an electric vehicle primarily, and have a very small displacement, high efficiency engine. This engine would power an electric generator for supplemental power for the batteries.  This very small, high efficiency engine (turbo diesel, or maybe even a turbine) would run continuously at constant speed while the vehicle is moving down the road, and also as a stationary power source when the vehicle is stopped. This would be ideal for a VW camper. It would operate as follows:

 

Plug in your camper several days before your trip

Start your generator and take off on your trip

Drive all day on battery power supplemented by generator power

Stop at a campground and keep the generator going until the batteries are fully charged again

Next day, the process is repeated.

 

You could add fuel or plug in as your trip allows, and of course use solar panels while stopped for power as well.

 

As far as cost goes, none of this would make any sense if it ended up costing $10/mile to run your camper. The cost to convert and run has to be competitive. For example, the cost to renew the engine in a Vanagon, along with all the systems that support it, costs around $20,000, plus the relatively high cost of fuel to run it down the road. To compete, an all-electric or hybrid conversion would need to take into account that as the “competition,” so to speak.

 

All things considered, we just do not feel the timing is right for this idea. Not only because the technology required is changing literally monthly, but also because of the other technical or monetary challenges involved in developing such as system, and supporting it long-term.

So for now, it will remain on the (dream) drawing board…. 



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