valhalla360
No paticular place.
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Joined: 08/19/2009
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Sorry if I got the posts mixed up.
Just trying to understand the full costs for comparison.
How much was the big alternator on the truck (cost and output)?
I would argue that while the system can run the A/C, it isn't practicle for the typical user as 1-4 hours per day would just get me grief from the wife when the voltage gets too low and the A/C has to be shut down on a hot sticky night.
Tammy Mike & the Bilge Rat (AKA: Diego)
Ford F250 7.2L
1997 Sunnybrook 27' 5er
1995 Gemini Sail Catamaran 34'
Full Time spliting time between boat and 5er
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pianotuna
Regina, SK, Canada
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Joined: 12/18/2004
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Hi valhalla,
It is the stock 130 amp alternator--but there are two battery banks and two charging solenoids--I can charge either bank independently of the other at up to 60 amps per bank. The wire sizes were increased to allow this to happen.
I am looking to get a larger alternator--but it must be totally compatible with the Ford V-10. There are some out there.
While I am driving I can run the roof air and still charge the batteries. So the 4.5 hours starts when I stop. Of course, since the RV is already cool that represents more than 4.5 hours.
valhalla360 wrote:Sorry if I got the posts mixed up.
Just trying to understand the full costs for comparison.
How much was the big alternator on the truck (cost and output)?
I would argue that while the system can run the A/C, it isn't practicle for the typical user as 1-4 hours per day would just get me grief from the wife when the voltage gets too low and the A/C has to be shut down on a hot sticky night.
Regards, Don
Kustom Koach Class C 28'5" 256 watts solar, 875 amp hours in two battery banks 12 volt batteries 2500 watt inverter.
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pianotuna
Regina, SK, Canada
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Hi valhalla,
I tried to send this as a private message--but I'm not on your list.
I've documented the growth of my system with costs at:
Technology
And click on Solar Boondocking.
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Oldtymeflyr
Littleton, CO
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Joined: 04/18/2004
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A generator takes time and attention.
It is distracting and noisy, when it should be quiet and peaceful.
These are costs that I am not prepare to make with the short time I have camping.
Go solar and reduce your use of electricity, get used to it.
Good Luck.
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bananadanna
Cambridge, MA
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Joined: 11/30/2005
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There are some unmentioned costs here.
Solar:
An empty roof rack typically exacts about a 5% mpg cost on a car. Let's guesstimate that a couple of solar panels are equal to a roof rack in wind resistance. Let's wave some more hands and call an rv half as slippery and reduce that to 2.5% added resistance.
So for a 15 mpg rv traveling 15k miles in a year the wind resistance cost is:
$3/gal x 1000 gal x 2.5% = $75/yr.
A rule-of-thumb with a car is that 250 lbs cost 1 mpg. If we say a solar panel or small gen plus batteries weighs that much we get added fuel cost of about 70 gals/yr. Let's go with half that to be conservative. That still adds around $100/yr.
So a typical solar set up has $175 per year in extra costs over a shore-power set up. That adds $1750 over 10 years. Pretty shocking what weight and wind resistance do.
Note that carrying a gen inside (with an extra fuel tank?) plus some batteries incurs the weight cost but largely avoids the wind cost. Perhaps $750 saved over 10 years.
Lots of fun watching the costs move around for shady northerners like me with 60% of the AZ insolation. Lots of camping days drives down the solar cost since you're not "wasting" those watt-hrs. All sorts of differences caused by your miles/year (and how much you speed.)
We average around 150 miles/day over our total vacation time. That's enough for me to live almost entirely off of alternator watt-hrs. No solar needed if you drive frequently enough. (Four house batteries--about 250 lbs) I own one of those Honda eu2000i gens but rarely need it for our style of mobile camping. I shudder to think what the hourly cost of operating it is since it has so few hours to amortize. I'd like to think the gen set displaces a night of motel if we need the extra watt-hrs for some special reason.
I have considered solar but I have an enormous canoe roof rack. Solar costs are dropping about 1% per month. Sorta wasteful for my needs---it'd just let me burn extra watt-hrs. Not in a hurry here as systems improve.
Dan
02 Freightliner Sprinter 2500 long tall home brew conversion
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pnichols
Santa Cruz Mountains
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Joined: 04/26/2005
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This entire discussion thread has been very interesting and educational.
Here's an excellent article on some RV electrical power options and when/how to use them. It's a little off-topic, but is related and very infomative for the curious. Even though it's from a specific Class B manufactuer the principles and methods talked about apply to all RV types:
http://www.sportsmobile.com/1_heating_ac.html
Phil, 2005 E450 Itasca 324V Spirit
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valhalla360
No paticular place.
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Joined: 08/19/2009
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We are full time travelers. Still sorting out how much we will use the generator with the 5th wheel.
I actually find the smooth hum of the engine to be soothing. Also, I'm not willing and more importantly my wife isn't willing to rough it on a permanent basis, so a ready supply of electrons helps minize the roughing it.
On the water, it made a lot of sense to use the generator, as many areas had expensive marina prices $50-80/night and with a typical travel day of 20-30 miles, you can't just bypass an expensive area.
So far with the 5th wheel we are staying under $20/night staying at reasonably nice parks. Not high end, but clean, comfortable and easy access to the freeway. But right now we are focused on getting south to warm weather, so we aren't really exploring some of the state and local parks along the way where electricity may not be readily available. In another week or so when we get into Texas, our criteria for where we stop should change.
Great discussion, but the more I see the best answer is more a function of how you use it as opposed to which system is better.
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Salvo
California
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I bet solar panels have no impact on a MH's fuel efficiency. Fuel efficiency is already very low that adding a small drag won't make any difference.
A car and MH are two different animals. Wind resistance does not scale.
Sal
bananadanna wrote:There are some unmentioned costs here.
Solar:
An empty roof rack typically exacts about a 5% mpg cost on a car. Let's guesstimate that a couple of solar panels are equal to a roof rack in wind resistance. Let's wave some more hands and call an rv half as slippery and reduce that to 2.5% added resistance.
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pianotuna
Regina, SK, Canada
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Hi bananadanna,
That's a nice analysis on the wind resistance--thanks for bringing up. I imagine it goes up by the cube of the speed?
Two of my panels are on the rear 1/3 of my RV--where there is already an existing roof rack, one of those two is behind a sky light and the other behind a vent. Of the other two, one is directly behind the air conditioner, and one is to the driver's side of the air conditioner. It may be that the one beside the air conditioner adds some wind resistance. They do stand 2 inches proud of the roof.
There are also panels that adhere directly to the roof. Their addition to wind resistance would be extremely low.
As far as weight, however, my four solar panels, including mounts, and wire clock in at only 80 pounds (and that's being generous--the panels are only 14 lbs each)--but then my panels have no glass.
A small generator weighs in at under 100 pounds wet--mine is slightly larger at 125 pounds (and 2800 watts)--but I now leave it behind.
A Ford Taurus weighs in at about 3700 pounds. A Class C is about three times that--so the penalty on weight would need to be 750 lbs per one mile per gallon. Even a "heavy weight" generator and/or solar panels would not come close to that number. I think the larger the RV is the less the weight factors in.
So, in my particular case the weight numbers are lower--except that very few RV's get 15 mpg. I'm currently getting about 11 mpg (US). Of course there are no free lunches with carrying weight--but at 80 pounds it is a fairly minor concern. Perhaps 1/8 of a mile per gallon?
I really doubt that most alternator charging systems are able to "top up" a battery bank in three hours (150 mile @ 50 mph), particularly if we assume 450 amp-hours of capacity. In general such charging systems in RV's are fused at 60 amps, and come with relatively puny wire. So the most a normal RV would "get back" is 180 amp-hours--and then only in the "window" from 50% to 80% state of charge. Doing that from time to time is OK--but doing it daily is a recipe for early battery replacement.
bananadanna wrote:There are some unmentioned costs here.
Solar:
An empty roof rack typically exacts about a 5% mpg cost on a car. Let's guesstimate that a couple of solar panels are equal to a roof rack in wind resistance. Let's wave some more hands and call an rv half as slippery and reduce that to 2.5% added resistance.
So for a 15 mpg rv traveling 15k miles in a year the wind resistance cost is:
$3/gal x 1000 gal x 2.5% = $75/yr.
A rule-of-thumb with a car is that 250 lbs cost 1 mpg. If we say a solar panel or small gen plus batteries weighs that much we get added fuel cost of about 70 gals/yr. Let's go with half that to be conservative. That still adds around $100/yr.
So a typical solar set up has $175 per year in extra costs over a shore-power set up. That adds $1750 over 10 years. Pretty shocking what weight and wind resistance do.
Note that carrying a gen inside (with an extra fuel tank?) plus some batteries incurs the weight cost but largely avoids the wind cost. Perhaps $750 saved over 10 years.
Lots of fun watching the costs move around for shady northerners like me with 60% of the AZ insolation. Lots of camping days drives down the solar cost since you're not "wasting" those watt-hrs. All sorts of differences caused by your miles/year (and how much you speed.)
We average around 150 miles/day over our total vacation time. That's enough for me to live almost entirely off of alternator watt-hrs. No solar needed if you drive frequently enough. (Four house batteries--about 250 lbs) I own one of those Honda eu2000i gens but rarely need it for our style of mobile camping. I shudder to think what the hourly cost of operating it is since it has so few hours to amortize. I'd like to think the gen set displaces a night of motel if we need the extra watt-hrs for some special reason.
I have considered solar but I have an enormous canoe roof rack. Solar costs are dropping about 1% per month. Sorta wasteful for my needs---it'd just let me burn extra watt-hrs. Not in a hurry here as systems improve.
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LarryJM
NoVa
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Joined: 11/09/2007
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T_Bone wrote:sh410 wrote:Purchase price: 875. USD Amortized over 10 Yrs 87.50 USD
One of the reason for generators with eco switch is that it reduces fuel consumption.
Fuel cost per hour: 3.50 USD/6hrs= 0.583 USD
Cost of oil change every 100 hours: 1/2 qt 2.00 USD/2= 1.00 USD
Cost of maintenance: Air Filter Washable, Spark Plug 3.00 USD /yr.
Hours Used per Year: 200
Cost Per Year in USD:
Unit Cost 87.50
Fuel Cost 116.67
Cost of Oil 2.00
Maint. 3.00
Total Annual Cost 208.17
Solar PV cost, 260w = $570
Charge controller= $200
Total PV cost for 20yrs= $770/20= $38.50/yr
Zero maintance other than a little water to clean the face.
50,000ahr available yearly
NO NOISE what so ever... 
Generator total cost for 20yrs =$4163.40
Try and making coffee or the microwave or using an electric space heater on that solar system ... it will loose every time when you factor in the cost of the inverter to get that 110V power. And then try and recharge your batteries maybe 2 or 4 six volt Trojans that you have used overnight to say 50 or 60% capacity the next day on top of making that coffee the next morning, before the sun is up on just solar .. again another no go. Generators have their place as does solar, but IMHO something like a Honda 2000 is so much more flexible over solar it's a no brainer IMHO.
Larry
2001 standard box 7.3L E-350 PSD Van with 4.10 rear and 2007 Holiday Rambler Aluma-Lite 8306S Been RV'ing since 1974.
ALL TRAILER MODS>>ETERNABOND INSTALL>>RAINKAP INSTALL
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