Basic RV Solar System

[cire]

I am new to this forum and the whole solar energy discussion and frankly I had no idea of the complexity and number of system options out there.

We have a 23ft 2012 Nash holiday trailer that we would like to add solar capability for the primary purpose of maintaining our batteries while camping (we live in Alberta, Canada - use our furnace most nights, even in the summer and use some lights) and to maintain our batteries between camping trips. We do have a Honda eu2000i Generator for the coffee maker, but I could see value being able to utilize the solar system to occasionally and quietly watch tv or a movie at night.

I was simply going to buy a 150 solar system from someone like "Go Power" on the recommendation of the RV Dealership that sold us our trailer. After reading many posts within this forum and conducting a bit of resarch, it appears that for a similar investment, I could build a much better system.

My trailer is prewired for solar capability. In that there is a preinstalled wire from the roof to a predetermined location for the controller and another set of wires from the controller location to the batteries.

I am really looking for advice to build a simple system. I am thinking about a 150-200 watt panel (best type of panel - Monocrystalline, Grid Type, Manufacturer - for this basic system). I now think a MPPT Charge Controller is the way to go (TriStar Product? - Is Sun Saver good enough or Pro Saver, or TriStar - 30amp). I have two 6volt deep cycle batteries (flooded?). How about a 500 - 1000 watt inverter (would this make a simple system too complicated - good quality - could I add this on later?).

I would spend up to $1000cdn. Shipping small items from the USA is ok but I wonder if shipping a large item like a panel from the USA would be cost prohibitive.

Any help would be appreciated.

Thanks, Travis

[solar pete]

Howdy Travis and welcome to Solar Panel Talk, sounds like your on the right track if you have been reading the stickies. You should be able to find a local shop to get a panel and racking from (but I have no idea where you are so maybe not) the small 12volt stuff is not my gig but there might be someone by to help at some stage, cheers.

[cire]

Thanks for the reply. I live just outside Calgary. I read through the permanent posts, a lot of good information. Maybe a little technical for me so I read through them many times to try to understand. Some of the "evaluate my setup" are very good as well. There are several experts on here that provided a lot of insight.

I am getting a handle on the basics, but it' s difficult to sift through all the setups to find something that is practical for my needs.

[jony101]

I would highly recommend you get at least a 240 watt or higher solar panel especially if you have the room for it. i got one on the roof of my astrovan, in your trailer it should easily fit, maybe 2 of them. A large panel is something you wont regret buying, with a small panel you are always going to be disappointed with its weak output.

A large panel will give you real power. I rarely drain my battery below 12.4 volts and I see a max of 11 charge amps. Recently I drained my battery to 12.1 and the next day i was seeing up to 15 amps of charge power. This is with the panel lying flat on the roof. Once you experience that kind of performance you dont want to get anything smaller.

i have a cheap (102.00 dollar) ecoworthy 20 amp mppt, been using it nonstop 24/7 for 2 years, its proven reliable for me. You dont have to spend alot of money to get a decent system. I bought my solar panel used for 200 dollars. You already have batteries, only upgrade them if you need new ones.

Myself I'm 100 percent solar, no generator, no isolator. My house battery is only charged by solar.

Its better to produce more power than you need, than to need power and not have it.

[donald]

You will want to know the prewire wire size before buying a panel. A larger 24v panel should work. Your panel will never have optimal sun orientation.

[SunEagle]

You will want to know the prewire wire size before buying a panel. A larger 24v panel should work. Your panel will never have optimal sun orientation.

Good points on the determining the wire size and a lower production due to panel orientation.

That is why going with multiple panels in parallel works because it will keep the amp load down on the wire and provide a little more production due to those panels being flat.

The same understanding of either using some type of "tracking system" to aim the panels at the sun or just use more panels all pointed the same way. More panels is usually less expensive than the cost to install and maintain a tracking system.

[donald]

Starting from the beginning, the system needs a good battery charger to use on 120v (I assume the trailer is plugged in at home). The system needs a volt meter. Lighting should be LED. The current batteries, if old, are probably part of the energy shortfall problem. If the furnace is run until the batteries die, then the batteries are likely no good.

Another issue may be camping in shade. In this case, getting new larger batteries with no solar, and properly monitoring charge will be the least expensive solution. This may allow two nights with furnace. Alternately, a portable solar panel set in the sun may work.

You will want a 120v charger that can equalize the batteries (assuming flooded) and maintain proper voltage. A smaller inverter (150-300 watts) should be fine. You have the generator to handle occasional heavy loads.

The right way to do this is to calculate daily cold weather energy use.

The best use of your money may be new batteries, a Guest marine battery charger (~$200 cdn), a battery monitoring system, and an inverter just big enough to run the TV. This allows you to properly charge the batteries at home, and with your nice Honda generator when camping.

Your routine then would be to start the honda in the morning, and charge the batteries while making coffee.

[RodK]

I am new to this forum and the whole solar energy discussion and frankly I had no idea of the complexity and number of system options out there.

We have a 23ft 2012 Nash holiday trailer that we would like to add solar capability for the primary purpose of maintaining our batteries while camping (we live in Alberta, Canada - use our furnace most nights, even in the summer and use some lights) and to maintain our batteries between camping trips. We do have a Honda eu2000i Generator for the coffee maker, but I could see value being able to utilize the solar system to occasionally and quietly watch tv or a movie at night.

I was simply going to buy a 150 solar system from someone like "Go Power" on the recommendation of the RV Dealership that sold us our trailer. After reading many posts within this forum and conducting a bit of resarch, it appears that for a similar investment, I could build a much better system.

My trailer is prewired for solar capability. In that there is a preinstalled wire from the roof to a predetermined location for the controller and another set of wires from the controller location to the batteries.

I am really looking for advice to build a simple system. I am thinking about a 150-200 watt panel (best type of panel - Monocrystalline, Grid Type, Manufacturer - for this basic system). I now think a MPPT Charge Controller is the way to go (TriStar Product? - Is Sun Saver good enough or Pro Saver, or TriStar - 30amp). I have two 6volt deep cycle batteries (flooded?). How about a 500 - 1000 watt inverter (would this make a simple system too complicated - good quality - could I add this on later?).

I would spend up to $1000cdn. Shipping small items from the USA is ok but I wonder if shipping a large item like a panel from the USA would be cost prohibitive.

Any help would be appreciated.

Thanks, Travis

I am also in Canada and have been shopping solar for my motorhome. I think I have my system picked out.

I am going to get 2 200 watt panels from 2solar.ca .
I am going to get a midnite kid mppt charge contoller.
I do not have any prewiring to work with so I have to purchase all that as well.

I should be able to build this system for about $1000 cdn taxes in.

I hope this helps to give you some ideas. I am a total solar newb but I have been reading A LOT!

Good luck.

[cire]

Starting from the beginning, the system needs a good battery charger to use on 120v (I assume the trailer is plugged in at home). The system needs a volt meter. Lighting should be LED. The current batteries, if old, are probably part of the energy shortfall problem. If the furnace is run until the batteries die, then the batteries are likely no good.

Another issue may be camping in shade. In this case, getting new larger batteries with no solar, and properly monitoring charge will be the least expensive solution. This may allow two nights with furnace. Alternately, a portable solar panel set in the sun may work.

You will want a 120v charger that can equalize the batteries (assuming flooded) and maintain proper voltage. A smaller inverter (150-300 watts) should be fine. You have the generator to handle occasional heavy loads.

The right way to do this is to calculate daily cold weather energy use.

The best use of your money may be new batteries, a Guest marine battery charger (~$200 cdn), a battery monitoring system, and an inverter just big enough to run the TV. This allows you to properly charge the batteries at home, and with your nice Honda generator when camping.

Your routine then would be to start the honda in the morning, and charge the batteries while making coffee.

Thanks for the input. I would assume all chargers are not created equal. I would think the charger that came with the trailer is a cheap one. If I replace my batteries would I be better off with two 6volt Golf Cart Batteries or two 6volt deep cycle (series 27) batteries. The Golf Cart Batteries are $130 and the Flooded Deep Cycle Batteries are $110 each at Costco(need to compare the amp hours?).

Going with a 250 watt 24volt panel and a 20 amp MPPT CC would be a good combination as long as my existing pre wire is large enough to support the load?

Thanks, Travis

[donald]

If you think you will keep the trailer a long time, then it may be worth getting a good 120v battery charger. One that allows you to equalize the batteries. If you think you may sell it within a couple years, I suggest you make do with what you have. I'm assuming the charger sold with the trailer is cheap and doesn't do equalization. I suggest looking at the better marine chargers. There are probably some better 120v noname chinese chargers, but I don't know the off brands.

Alternatively, if you can periodically borrow a battery charger that can equalize, you might want to make do with the unit you have. I'm not sure how to quantify the benefit of a more expensive battery charger, considering the small battery bank. You only have a couple hundred dollars worth a batteries.

I would select a panel over two hundred watts based on total price and physical fit. Either the one you mentioned , or two smaller 12v in series. Bargains are good, as long as the panels are made by a known company. Check ebay ca for prices. Know how and where you're going to mount the panels before purchase.

24v from the roof will require an 15A MPPT controller. I see Victron makes a $100 solar controller, which surprised me. I don't know the unit, but Victron wouldn't put their name on junk. So I suggest doing some research and maybe save $100.

The costco batteries may be a good deal if the amps are close. There should be conversations online as to who makes the costco batteries. You need to be able to monitor the voltage of the batteries when camping, and keep the pair above 12v. And remember that batteries are used up. Treat them well and you will be doing well with 3/4 years of use. When you can no longer run the furnace overnight and have the batteries above 12v in the morning, its time to start planning for new batteries. When its freezing and the batteries are dead at 2am solar panels are not much value. Understanding and managing batteries is more important than adding solar. Especially considering you already have a nice generator.

If you want to sit in the trailer some evenings watching TV with the furnace running you need to be concerned about battery capacity. Personally I wouldn't plan to do this on only 225ah of storage. But the alternative approach is to just assume that two T105 type batteries will only last two seasons. ~$150 per year battery budget isn't particularly expensive.