Motorhome – Unique for Battery/Hybrid – NextGen Powertrain Concept

[swduns]

Motorhome manufacturers can now massively improve fuel mileage
Motorhomes are uniquely suited for Battery/engine hybrid powertrains
The nature of the usage of motorhomes drives this
The first motorhome manufacturer to deliver these benefits will garner a huge market share

Motorhomes cruise – a predominance of their travel is spent cruising on interstate
Motorhomes need generators – they already have that weight
Traditional motorhomes carry large fuel tank with significant weight
Motorhomes already carry coach batteries
Motorhomes travel – they can’t be dependent on long recharge times
Motorhomes boondock – extended off grid capability would be a benefit

Battery/engine hybrid:
The Battery/electric motor provides torque/acceleration
A small engine provides cruising propulsion/generator/charging
Battery/electric motor would assist on grades
Vehicle DC motors have incredible torque at very low rpms – hence why their used
Vehicle DC motors are relatively small and light weight considering their torque

Difference from Hybrid car:
Engine/generator can recharge batteries

Difference from electric only motorhome:
Not dependent on stationary recharging and travel delays
Batteries only required for torque/acceleration
Engine/generator can recharge batteries

Unique synergies for motorhome & Battery/engine hybrid powertrains:
Motor home have a generator anyway. The engine/generator is offset by weight of normal engine and normal generator. Diesel engines/drive trains are very, very heavy.
A large battery bank would support extended boon docking
Engine/generator can recharge batteries overnight during travel or via shore power at overnight park
Battery weight is offset by:
• Smaller cruising engine required vs heavy diesel engine/drive train
• Traditional separate chassis engine & separate generator
• Smaller fuel tank for Smaller cruising engine
• Traditional chassis & coach battery weight

I had a Mazda RX-8 with a rotary engine. The rotary engines have 40% of the parts of a traditional engine. They are a fraction of the size of a traditional engine and light weight. I personally believe they would be well suited to serve as a cruising engine/generator. A rotary is not right for every car application but I think they would be ideal for this unique application.

I have also had two Chevy Volts. Very excellent cars. They are not just an electric car and they are not just a hybrid. They can operate with the gas engine only or operate as an electric car only. In reality when they operate on gas they are using the battery to function as a hybrid. This is similar to the concept I’m espousing here as opposed to an electric only motor home.

[CountryB]

I think electric drive-motor RVs will be coming - but not for a while.

The battery technology is not where it needs to be (long life and inexpensive) to make electric RVs affordable to the public.

A replacement battery for a Chevy Volt is around $2,000 (using the lowest cost per this article) https://enrg.io/how-much-does-a-chev...lacement-cost/

A 40 - 45ft Coach with GVWR around 50,000lbs would need probably 10 or 20 of these batteries.

Maybe after the Tesla semi and similar offerings, have been in service for a while (I think it will take a decade) the price of batteries will drop and the battery technology will improve to the point where an affordable electric RV will come to market.

[doc77]

Motorhome production is pretty fragmented, split between dozens of relatively low volume manufacturers, many just steps away from bankruptcy when the market enters cyclical downturns. I doubt any one of them has the technical expertise to develop such a concept.

Medium and heavy truck manufacturers have a much larger market, and it’s a little less cyclical, so they are better equipped to do this type of development. Once volumes are realized, costs will come down and the RV industry can adapt the paid for technology.

As for the Wankel engine, they are incredibly dirty and inefficient engines. Until the hydrocarbon emissions issue resulting from the high s/v ratio and combustion sealing issues can be resolved, there isn’t much future.

Same goes for the poor fuel economy, which runs counter to the idea of an electric or hybrid vehicle.

[swduns]

If an only electric motorhome then it would need an enormous battery pack
but if it is a hybrid where the battery is only for acceleration/torque ... it would not be 50x a volt battery back. Yes bigger, yes heavy but not impractical

Electric cars use batteries today and are practical. e.g. Teslas and other
Batteries aren't perfect and can be improved undoubtedly but the technology is already there for a practical hybrid/motor motorhome

This would be a game changer. No one would buy a conventional motorhome when a properly designed hybrid/motor motor home hits the market. Any motorhome manufacturer that doesn't adapt to this superior performance design will end up with no market share.

[tderonne]

Winnebago showed a hybrid motorhome concept twelve years ago.

Winnebago EcoFRED

[swduns]

motorhome manufacturers do leverage/depend on truck chassis manufacturer designs

I believe the case of a motorhome battery/motor hybrid has different requirements from a truck or a bus

if the motorhome manufacturers try to leverage a truck or bus hybrid it will be suboptimal for a motorhome

it would work but be suboptimal

whoever steps up and does it right will be in a league by themselves in terms of capabilities & performance

Think about it .... if motorhome fuel consumption were significantly improved ... it would make a major difference .... motorhomes would be more generally practical

[Argosy]

Originally Posted by swduns

motorhome manufacturers do leverage/depend on truck chassis manufacturer designs

I believe the case of a motorhome battery/motor hybrid has different requirements from a truck or a bus

if the motorhome manufacturers try to leverage a truck or bus hybrid it will be suboptimal for a motorhome

it would work but be suboptimal

whoever steps up and does it right will be in a league by themselves in terms of capabilities & performance

Think about it .... if motorhome fuel consumption were significantly improved ... it would make a major difference .... motorhomes would be more generally practical

Motor home builders are ASSEMBLERS of common parts readily available. They don't design toilets, refrigerators, air conditioners, or drive trains. They don't have the capability to step up and create a hybrid drive train, it will come from the engine builders.

I'm curious why you believe a hybrid system designed for a truck or bus wouldn't be optimal for a motor home?