cvbdsl wrote:
"Hybrid is doable but unlike passenger car operation, it doesn't work so well with an RV. Hybrid benefits are in stop and go city traffic, something most RV's avoid like the plague. RV's typical use is freeway driving where hybrids are pure IC engine driven. The big issue is they have much worse HP/weight ratios compared to passenger cars to begin with. This makes hill climbing a big issue. Regenerative brakes don't help if you can't make it to the top of the 10mile grade."
Not quite true - I have a hybrid and primarily drive 50 miles per day at roughly 50 mph to 65 MPH. Very little stop and go. My hybrid will travel at 70 MPH on electric until the battery needs recharging - once recharged (still at highway speed) the electric motor cuts in again. Same as if I'm doing 30 or any other speed. In fact I get lower MPG in stop and go traffic as you have to get the vehicle moving again - not running the engine at a stop light is offset by having to accelerate up to speed again. Constant speed is the best for my hybrid (getting 60+ MPG for the last two years now).
This is the way modern hybrids work - they use up the battery power and then the IC engine takes over to both move the vehicle and charge the battery. Once the battery is charged it goes back to EV mode. Repeat the cycle over and over.
My regenerating system starts when I take my foot off the accelerator and doesn't need the brake (transmission controlled). It also regenerates when braking but it actually has minimal input. Regenerative braking (according to my dash readout) provides only about 5% of EV power/distance. About 40% of my time is spent in EV power mode, but it does take a whole different approach on how you drive.
My current hybrid (2013) is miles ahead of my first hybrid (2005). The old hybrid did what you state above and would not use EV mode over 25 MPH and got better gas mileage in stop and go, but was not worth the extra cost. Overall mileage (with a lot of highway) was terrible.
So I agree with the OP, that a hybrid technology can eventually be used, but will also state that I think we are still quite a ways of from perfecting battery and electric motors/transmissions to make this happen. Also the benefits will have to outweigh the costs - i.e. have a major improvement in fuel mileage/maintenance without breaking the bank to get it.
What you describe in industry terminology is a plug in hybrid.
Works really well for a commuter car as most people can be served by a 30-40mile range for typical commuting with the motor kicking in when longer trips are taken. This is something like the Volt. Which while rated at something like 100mpg, drops to around 30mpg once it switches over to gas mode.
With a MH, typical trips are rarely that short and would require a battery pack an order of magnitude larger. The bigger issue is if you don't want a major drop off in performance, you need to keep the same size diesel in the MH...so what are you really saving by adding a lot of cost, complication and used up storage space?
