Hydraulic Generators

[pnichols]

I notice that the newest high end Earthroamer has a hydraulic generator on board.

I know that Earthroamer likes to talk about their vehicles not having onboard stand-alone generators. So I wonder what the RV advantages are of a hydraulic generator over a conventional stand-alone generator?

Doesn't a hydraulic generator require the main vehicle engine to be idling to run it's PTO to power the hydraulic generator? If so ... isn't high-idling of the Earthroamer's diesel engine going to be somewhat noisey and smelly .... just like with a conventional diesel generator (plus use more fuel than a small stand-alone generator)?

Here's a link to a typical hydraulic generator product that might be what Earthroamer is using: http://harrisonhydragen.com/?page_id=90

[MrWizard]

doesn't need to be governed
IF
they use a pump powered multiphase alternator head and inverter electronics ?

i think this is a case of a solution looking for a problem
like one post suggested "cost is no object, its about bragging rights"

[GordonThree]

Wouldn't they have the same problem with a hydro system as well, unless they're using an electric pump instead of a belt drive? With gearing, belts, etc they can convert rpms up or down, but it still needs to be constant, still needs to be governed somehow?

[DrewE]

GordonThree wrote:
Why don't they just slap a 110 or 220 generator head on the main engine accessory belt or better yet on the PTO?? Then they don't have to mess with a hydraulic system.

That works nicely if you have and use a constant speed governor on the engine. PTO attached generators are not hard to come by for tractors, for example. I'm not so sure many road vehicles would have the required controls; I think for most with a PTO about all they have is a manual throttle control (but not a governor).

[GordonThree]

Why don't they just slap a 110 or 220 generator head on the main engine accessory belt or better yet on the PTO?? Then they don't have to mess with a hydraulic system.

[theoldwizard1]

MrWizard wrote:
run the drive engine, to power a hydraulic pump , too spin a generator

something here doesn't make sense to me

1st and 2nd Law of Thermodynamics.

When you convert one form of energy to another, you can't win. You can't even "break even".

[time2roll]

Going to save weight, space, maintenance. I assume exhaust will be cleaner with an emission controlled diesel vs Onan or equivalent diesel. I also assume 6+ kW. Low cost is probably not part of the thought process.

[MrWizard]

run the drive engine, to power a hydraulic pump , too spin a generator

something here doesn't make sense to me

i understand the use, in heavy equipment or military vehicles with other hydraulic needs

but in an RV ?

the only thing i can say about it is, separate components so less space is taken up in the RV section, by the generator, more cost,

[DrewE]

It would be handy if you frequently camp at a place where they have high pressure hydraulic oil hookups but no electricity at the campsites. I can't say I've seen a campground that meets that description ever, but none the less....

[GordonThree]

SidecarFlip wrote:
No positive benefit that I can see. You have to have the engine running and what good is that. Earth Roamer owners are way more flush than I am so they probably don't care anyway. It's a status symbol, nothing more.

x2 ... something to brag about sitting around a campfire built from bundles of cash.

[SidecarFlip]

No positive benefit that I can see. You have to have the engine running and what good is that. Earth Roamer owners are way more flush than I am so they probably don't care anyway. It's a status symbol, nothing more.

[Chum_lee]

Biggest disadvantage: Initial installed cost. It's got to be less than say . . . an Onan 4kw genny or what's the advantage? Noise, . . maybe but the vehicles they are designed to be used on are far from stealthy.

Chum lee