Dual alternator as a generator

[Hodag1]

On the EarthRoamer site they say;
"We order Ford F-550 turbocharged diesel Power Stroke trucks with the dual alternator option which provides a quiet, fuel efficient, factory installed 3.7 kWh generator. We install an advanced battery isolation system and connect the factory alternators using low resistance, #4/0 tinned copper marine cable to the massive absorbed glass mat (AGM)camper battery bank. Whenever driving or the engine is idling, the AGM battery bank is being charged by the high output dual engine alternators. At idle, the Power Stroke diesel burns approximately .5 gallons of diesel per hour which is significantly less than many RV generators at full load."



I have a 2011 F350 6.7 diesel with dual alternators. Has anyone on this forum done this? Is there a source of premade cables and ancillary hardware to accomplish this?

[Hodag1]

357 Amps with the dual alternators

[Buzzcut1]

steve68steve wrote:

Buzzcut1 wrote:
At idle, the Power Stroke diesel burns approximately .5 gallons of diesel per hour which is significantly less than many RV generators at full load."

that is flipping nuts. $4/ hour or $32/8 hours to run a generator if the fuel is at Ca prices of around $4.00/gallon. I'll take the Honda 2000 using two gallons of $3.75/ gallon gas to run flat out for 8hrs. And not coke up my engine

You missed the "1/2" in your calculation - it's $2/ hour. It may cost only $7.50 to run a Honda 2000, but it also costs $1000 to by it. You'd have to put quite a few hours on it until you started realizing a savings over idling diesel (provided your diesel was already set-up to charge).

Big diesel engines (trains, ships, back up power generators, etc.) run/ idle continuously - or at least used to, unless they're brought down for service. Idling is child's play for a diesel.

On the newer Diesels they specifically say not to idle them for extended periods ( at least on the powerstrokes they do) as the turbos, valves and egr coke up.

[steve68steve]

Buzzcut1 wrote:
At idle, the Power Stroke diesel burns approximately .5 gallons of diesel per hour which is significantly less than many RV generators at full load."

that is flipping nuts. $4/ hour or $32/8 hours to run a generator if the fuel is at Ca prices of around $4.00/gallon. I'll take the Honda 2000 using two gallons of $3.75/ gallon gas to run flat out for 8hrs. And not coke up my engine

You missed the "1/2" in your calculation - it's $2/ hour. It may cost only $7.50 to run a Honda 2000, but it also costs $1000 to by it. You'd have to put quite a few hours on it until you started realizing a savings over idling diesel (provided your diesel was already set-up to charge).

Big diesel engines (trains, ships, back up power generators, etc.) run/ idle continuously - or at least used to, unless they're brought down for service. Idling is child's play for a diesel.

[Wes_Tausend]

...

The 3.7 kWh claim seems a bit high. 3700watts/12volts = 308 amps, so such an output would require slightly over two 150 alternators run at maximum. What is the amp rating on the Ford alternators?

It is possible to run ordinary automotive alternators at a higher voltage, say regulated at 24v, and then 3700w/24v = about 154 amps, or 75 amps per alternator which seems closer to reasonable if they are 80 amp units, and can stand full output for extended periods. It would be a bit tricky to charge at 24v and draw at 12v off the same battery system, though.

Through some simple hardware store wiring, a disconnected-from-12v-system alternator will also casually run up to 110vdc and drive any ac/dc brush type tool motor (drill, circular saw etc.) or 110v filament (bulb, heater). Therefore a small 40 amp alternator can put out 110v x 40 amps = 4400 watts (4.4 kWh). I don't think they are designed for a 100% duty cycle at full output though.

Temporarily bypassing the voltage regulator was a Ford shop test back in the sixties. A healthy 40 amp alternator would peg its ammeter at said 40 amps, at high idle, all juice dumped into a good automotive starting battery for a short time.

Wes
...

[Greg_B]

Yea, probably not a good idea to idle a new DPF diesel for hours on end.
I too like my little Honda. It'll run all night on the 1 gallon tank.

[Buzzcut1]

At idle, the Power Stroke diesel burns approximately .5 gallons of diesel per hour which is significantly less than many RV generators at full load."

that is flipping nuts. $4/ hour or $32/8 hours to run a generator if the fuel is at Ca prices of around $4.00/gallon. I'll take the Honda 2000 using two gallons of $3.75/ gallon gas to run flat out for 8hrs. And not coke up my engine

[Shadow_Catcher]

I can also charge from the TV alternator if solar is not enough (bad weather). One thing you might want to look into is a Balmar regulator/smart charger http://www.balmar.net