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.
One concept we have been working on here at GoWesty is an add-on electric drive for the front axle of any Vanagon. The concept is to replace the entire front suspension and steering with a removable subframe that houses an electric motor that runs the front wheels only, and a battery pack or packs mounted in otherwise unused space under the vehicle. The electric motor would double as a generator so when you are cruising down the road at a steady speed some of the engine power would be used to recharge the batteries. Whenever the vehicle was decelerating (off-throttle), the energy would also be collected and stored in the batteries instead of wasted as heat in the braking system.
The idea is threefold:
1) On-demand extra power for climbing highway grades
2) Adding 4WD capability to a 2WD Vanagon
3) Improving fuel efficiency
Fast forward to 2022 and we built ourselves a prototype: NORRA Race van #421! This van was originally a 2WD which we converted to a standard Syncro with driveshaft connecting the transaxle to the front differential. We removed the driveshaft and installed an electric motor to the front Syncro differential to make it an electric hybrid. We built this van as a proof of concept, raced in the 2022 NORRA 500, and the damn thing worked! But don’t get too excited—an actual off-the-shelf GoWesty Hybrid conversion kit is far, far away—if it ever materializes at all!