| Author | Message | ||
| RJ mueller (Rjmule)
Registered Member Username: Rjmule Post Number: 1 Registered: 2-2007 Posted From: 75.51.70.24 Rating: N/A |
I'm just starting my conversion and want to get power to it pronto. I would like to go solar because of expenses although i know intial setup is costly. I have the opportunity to purchase an onan 12mdl3p generator with a cummins 4 cyl but it's a 1992 model. the owner (said) it works but it's not installed so i can't hear it. He's asking $2000 for it but i think it maybe overkill for my application.i'm going to install 2 roof airs plus the other normal junk. Not sure what to do. will solar be enough. I've seen charts informing how many panels needed etc etc.Pulling My Hair.any help would be app. thanks | ||
| Sean Welsh (Sean)
Registered Member Username: Sean Post Number: 537 Registered: 1-2003 Posted From: 67.45.244.133 Rating: N/A |
There is no way to put enough solar panels on a motor coach to run two air conditioners. So, if that's your question, then, no, solar will not be enough. That being said, solar panels can certainly reduce your dependence on the generator for other things. Everything is a trade-off. Solar photovoltaic panels cost between $5 and $6 per "watt". How many watt-hours per day, on average, you can get out of one "watt" of solar panel depends on many things, like where you are parked, whether or not the panels are tilted, and how many days of the year will be sunny. I tend to figure only about one or two watt-hours per day, average, per watt of panel. That means your $5 of solar panel buys you, roughly, 500 watt-hours (or one half Kilowatt-Hour, KwH) per year. To put this in perspective, residential power from the grid costs roughly $0.10 per KwH. So it would take 100 years to pay back solar panels at that rate. (Before anyone jumps on me -- yes, I know that real-world payback for fixed dwellings is much faster than that -- but they have the advantage of fixed location, optimum tilt, minimum shading, and time-of-day power cost differential). However, in your rig, your cost for power is likely much higher. For example, if you stay in an RV park just to get power, and stayed only long enough to fully charge a large battery bank, you would be looking at something like $30 for 70 KwH, or $0.43 per KwH. At that rate, you would pay back your solar in about 23 years. But even more realistic still, out in the boonies (where solar comes into its own) and away from sources of cheap commercial power, you would be looking at running your generator. If you have, say, an 8Kw genset, and it runs 0.8gph (a common figure) and needs oil, filters, etc, every 200 hours, and your charging efficiency (the ability to take that energy and translate all of it directly into battery charge) is say 50%, then you are looking at $0.90 per KwH. At that rate, it will take only 11 years to pay back your solar investment. The above figures are just guidelines, of course. You might spend all your boondocking time in the Arizona desert, where solar efficiency is the highest. Or you might get better fuel consumption on your generator set, or more charging efficiency. So these paybacks could be off by a factor of two in either direction. All bets are off, of course, if you need power in a place where generators are forbidden, such as some National Park campgrounds. In which case solar may be your only option. Just don't plan on using it to run an air conditioner. -Sean | ||
| Kevin Hunter (Sourkraut)
Registered Member Username: Sourkraut Post Number: 3 Registered: 1-2007 Posted From: 70.69.177.119 Rating: N/A |
From what i understand solar panels are for charging batteries. They wont run roof air unless they are the size of the space station.hehe Gen set is a must have. The other people on this board maybe able to help you if you have picture,s or more detailed info on the one your looking at. Dont sweat the small stuff. | ||
| jim morrison (Jim_morrison)
Registered Member Username: Jim_morrison Post Number: 77 Registered: 11-2006 Posted From: 72.142.29.218 Rating: N/A |
pannels will not run roof air. i have 2- 100 watt, pannels that run everything on board , i don't like air cond, so thats no problem for my set up, but i do alot of boondocking, so it helps me, you might try a gen, and pannels , but it will cost you more , most folks on this board run gen's, and do the shore thing , every one has their own application to fit their needs , but to have the back up energy is nice, hope this helps, jim | ||
| Richard Bowyer (Drivingmisslazy)
Registered Member Username: Drivingmisslazy Post Number: 1830 Registered: 1-2001 Posted From: 75.108.87.29 Rating: N/A |
I find it hard to believe that anyone can run thru the southwest with A/C. I know I could not and if I had to live like that I would move up north, way north. In my travels across the country it was very common to run the genset several days 24/7. Richard | ||
| joe padberg (Joemc7ab)
Registered Member Username: Joemc7ab Post Number: 82 Registered: 6-2004 Posted From: 66.38.159.33 Rating: N/A |
Richard It depends on the time of year you are there. Quartzite in February is very bearable, But July would be another story.... Joe. | ||
| jim morrison (Jim_morrison)
Registered Member Username: Jim_morrison Post Number: 78 Registered: 11-2006 Posted From: 72.142.29.218 Rating: N/A |
yep , when i travel it's cold here , but i do like the warm stuff, when i was in south Mex, it got warm but a fan does wonders, i don't have any air just fans right now it's - 5 deg's and with the wind it's - 20 deg's i hate the cold , can't do a thing when it's this coldbut when it'a warm i can do most things , hope you under stand, we live in a cold climit here and it's hard to move around untill the warmer stuff comes this way......jim | ||
| Bob greenwood (Bob_greenwood)
Registered Member Username: Bob_greenwood Post Number: 695 Registered: 7-2006 Posted From: 64.136.49.228 Rating: N/A |
guess you people don't want to hear about 70's & 80's that are happening now then | ||
| jim morrison (Jim_morrison)
Registered Member Username: Jim_morrison Post Number: 81 Registered: 11-2006 Posted From: 72.142.29.218 Rating: N/A |
i was there last winter Bob had a great time and it was warm most of the time , but no can't say as i want to here about how warm it is right now lol sorry, i just hate the cold ..jim | ||
| Harmer (Dave_4104_in_victoria)
Registered Member Username: Dave_4104_in_victoria Post Number: 11 Registered: 2-2007 Posted From: 24.69.65.204 Rating: N/A |
hmmm, solar power. Well when w e started researching for our conversion, I wanted to keep it green to counter the smoke from the detroit, kinda like equalization, lol. Actually we ended up with two 100 watt solar panels. Two 8d batteries for the coach and we have three 8d's for the house, soon to be two as that is all we really need. Recently added an echo charger to keep the coach batteries topped up. This system was definitely more pricey than genset, but we sure like it. Solar will and is getting cheaper as with the LED stuff, just not quick enough. We had actually gone and ordered a composting toilet for the coach also, but found in the final moments of checking and rechecking with manufacturer that to operate at peak efficiency, it needed to operate with a 240 watt heating element. We did not risk it even though they said it would probably still work, When the technology gets there, we will likey put this in and recycle the black water tank along with gaining bay space back. A friend had a nice diesel,kubota genset in his coach, nice and compact. I did have a honda gas gen 1500 watt, but sold it, due to not using enough. I may go for a 1000 watt in future for emergencies or for high use times. Depending on your invertor, you could run some high ticket items with qen set backing up the batteries etc. Hope this helps a little. Dave out | ||
| jim morrison (Jim_morrison)
Registered Member Username: Jim_morrison Post Number: 82 Registered: 11-2006 Posted From: 72.142.29.218 Rating: N/A |
Dave your on the island my bro. inlaw is in Qualicome area , and he sells all this stuff , email me and i'll give ya his phone # if you want it , you'll be amazed .......jim | ||
| RJmule (Rjmule)
Registered Member Username: Rjmule Post Number: 4 Registered: 2-2007 Posted From: 75.51.70.24 Rating: N/A |
THANKS ALL,but im still confused, LOL, go wander, still cant figure out if the generator is a good price (deal),or overkill,again 12k onan with 4 cyl cummins diesel for 2000. | ||
| Kyle Brandt (Kyle4501)
Registered Member Username: Kyle4501 Post Number: 285 Registered: 9-2004 Posted From: 70.153.0.104 Rating: N/A |
Look around at what new diesel gensets sell for. I'd think that $2000 for a diesel genset in good working order is a good price. If you can't establish it is in good order, you are taking a chance. I'd locate a service center to take it to, if it passes their test, buy it. | ||
| Harmer (Dave_4104_in_victoria)
Registered Member Username: Dave_4104_in_victoria Post Number: 14 Registered: 2-2007 Posted From: 24.69.65.204 Rating: N/A |
sorry Jim, thought you wanted a comparison or opinions gen versus solar. I think i mis read it slightly. Otay 12 kw diesel onan, $2000, seems pretty cheap for that, so if you have it checked over and are satisfied, jump on it. I think it has been mentioned previously that it is not real practical to run air conditioner(s) off of inverter even with large battery bank with solar backing up. Don't have the math in front of me. 12 kw, you could probably sell some power to your generatorless neigbhors,  . Hope it helps. Dave out | ||
| JC Alacoque (Jc_alacoque)
Registered Member Username: Jc_alacoque Post Number: 25 Registered: 7-2006 Posted From: 154.11.98.45 Rating: N/A |
Our coach has a roof air for when we are plugged in to shore power. For boon docking and driving (no dash air), I installed a evaporative (swamp) cooler in the roof near the front. Works very well in dry climate out West. The pump and fan work off the same 12 volt motor that draws very little. The water supply runs from the bathroom sink's cold water line. You just have to have the water pump on for pressure. JC |