“Under hood generator”

For a while I entertained the idea of getting a Class B moho and joined 3 different makes FB groups to get myself familiarized with Class Bs.

If memory serves me right, Roadtrek may have been the pioneer in using the so called “under the hood generator”. I followed the groups for several months and came to the conclusion UHGs systems were fraught with problems and the reason some RV manufacturers use them is strictly to save money.

I'm old-school and prefer old-school generators to an alternator with a fancy name in the engine compartment. Onan recently came out with an inverter type generator for Class Bs and it is very quiet compared to the traditional generators.

On a van forum UHGs were mated with a Lithium battery so they could charge quicker. Very convenient - just start the engine. But costly, a much larger engine than needed is running when parked, run at a high idle RPM which sounds noisy and maybe harder on the environment. I would like to see a unbiased set of pros and cons.

Poking around online, the only "under hood generators" I found were large after market alternators paired with a large inverter to supply AC.

These can work but they come with some downsides:
- You are putting hours on your main engine which is likely far more expensive than a small dedicated generator. Ask about required RPM to generate the rated amperage. Most alternators need to run faster than idle to do more than low output.
- Large alternators get used on cruising boats frequently and due to the heavy loads, if they aren't perfectly aligned and tensioned, they tend to eat up belts and are hard on the bearings supporting the pulleys.

Now if it was mated to something like the hybrid F-150, that would be a different ball game.

Following. Sounds interesting.

Must be an inverter. The alternator makes DC