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hes4all · 11-02-2013, 08:16 PM

Thought I would share this with you all. While getting my coach ready for bed for winter, I went and pressed a few on the buttons on my solar controller. And in a one year period I used 7925 amp hours.

I do boondock 99% of the time so I wonder what that saved me in generator use?

Just wanted to share this.

Good day to you all!

RoamingGnome · 11-02-2013, 08:42 PM

7925ah x 120vrms is roughly 951kwh. Florida Power & Light billed me $180 for the 1730kwh I used in my Florida home last month. 951/1730=0.55 (what you used vs what I used). 0.55x$180=$99 so you saved about a hundred bucks.

MRUSA14 · 11-02-2013, 08:47 PM

Well, your generator doesn't provide power as cheaply as FPL does!

docj · 11-02-2013, 08:48 PM

Wouldn't the amp-hours measured on a solar controller more likely be 12V rather than 120V? That would be ten times less energy.

RoamingGnome · 11-02-2013, 08:54 PM

Yes if 12v then 10x less. I assumed he was measuring inverter output ah.

RoamingGnome · 11-02-2013, 09:25 PM

Quote:

Originally Posted by MRUSA14

Well, your generator doesn't provide power as cheaply as FPL does!

An Onan RV 5500 EFI uses 0.6 gph at half load which is 2750 watts, so 2.750kwh takes 0.6 gal of gas. A gal of gas costs about $3.20 for me these days so 2.75kwh costs 0.6X$3.2=$1.92. The 951kwh I figured in an earlier post (assuming 120v) would therefore cost (951/2.750)X$1.92=$664 saved. If the OP meant 12v amps used then the savings is more like $66.

vsheetz · 11-02-2013, 09:39 PM

I don't recall the specific numbers. Awhile ago I used a kill-a-watt meter to see what my coach used plugged in while stored/inactive at home. Calculated to be ~$10-$12/month. Albeit SoCal electric rates are likely higher than many places. Biggest portion of that power draw was the converter to charge the batteries. Now with solar on the coach I don't plug in anymore while stored/inactive at home.

hes4all · 11-02-2013, 10:13 PM

My last long trip of the year was 14 days of dry camping in Colorado. Never started the generator. My wife cooks about half the time using a slow cooking crook pot that pulls a fair amount of power. Plus I never turn the inverter off.

Also on this last trip my fridge went out on propane so the solar really saved me. The spark generator quit so I ran it off the inverter the whole time plus everthing else.

Might not save alot of money but I like it. Solar is really quite!

**CountryFit** · 11-03-2013, 12:04 AM

what are your battery capacity and solar wattage?

vsheetz · 11-03-2013, 12:26 AM

The OP lists 900w solar in their signature.

I have 600w on the roof and another 200w portable if needed. 4 Trojan 105 six volt batteries.

hes4all · 11-03-2013, 10:24 AM

Quote:

Originally Posted by CountryFit

what are your battery capacity and solar wattage?

As mentioned, I have 900 watts and at the present time. I have 6 agm's with 660 amp hours. I will be going to a larger battery or two more batteries when the present need to be replaced.

Some say that the 900 watts is over-kill. And I say that that might be correct if you boondock only in july or August. But I boondock in the winter and fall too. Plus I don't have to get on the roof and angle the panels during the summer months because of the 900 watts.

There are a few other reason too, like efficiency and power loss through connections and wire.

Thanks