solar budget of 2700.00 Canadian

[pianotuna]

Hi all,

I'm going to beef up my solar system. The budget is $2700.00 including installation costs.

I'm considering these because I will be able to pick them up from Calgary and save the (considerable) shipping costs:

poly 245 watt

or

mono 240 watt

Which would you choose for low light performance?

The ones on the roof will be non tilt. I am considering a "wing" on the rear of the RV. That would need to tilt--and cleaning may be an issue. (Cover with six mil poly while traveling? Any other brain storms?)

Assuming four to six panels, what MPPT controller would you choose?

I love my unisolar system. I may be removing it to allow for even more than six panels. I'd really rather keep it in place and simply add a second controller as an independent system.

[time2roll]

Monitoring voltage is sufficient IMO. Isn't there a battery monitor on this RV already?
Network cable or RS232 to USB will put all data to a laptop when needed.

[CA_Traveler]

OK, didn't realize the probe was included. But the remote monitor while it may not be needed - BUT he's in extreme low temperatures, 2 controllers both of which can be monitored within the comfy warm interior of the rig.

So does he need the monitor? Of course not but does he want to know if due to snow or overcast weather (probably why I no longer live in Michigan) he needs to drive around the block, plug in or be cold???

[time2roll]

The 60 has the probe included. Display is extra and unneeded IMO.

[pianotuna]

Hi CA T,

I thought the morningstar came with the temperature probes? I don't want a remote meter.

[CA_Traveler]

So: 6x269 + 2x510 + 2x25 (battery probes) + 110 (remote meter) = $2794 + installation, etc.

Oops 6 panels blows the budget.

[pianotuna]

Hi,

I'll be talking to the person who will be doing the installation for me in early May. Some serious measuring is going to have to be done.

[CA_Traveler]

Yes, 6 panels is huge for a RV. So your options are:
1. 6 panels and 24V.
2. 2 MS MPPT 60 controllers with 3 panels each. Find the space for the second controller.
3. 4 panels.

[time2roll]

CA Traveler wrote:
So the only real option for 6 panels is 2 controllers.

Three drives the MS MPPT 60 nicely. :B
But honestly I think you only need the 45 with three panels so 2x 45 would work well with six IMO.
The pair of 45s will save you ~$250

RickSo wrote:
I hadn't brushed the snow of my panels a few weeks ago when we had a good storm and when cleaned the meter was reading 673 watts and 45 amps because the batteries were down to 12.3 volts.

In winter you will be lucky to get 45 amps. In summer you will never need more than 45 amps.

[pianotuna]

Hi Salvo,

Thanks!

I expect I'll do as I did with the unisolar's and use angle aluminum along the long side of the panels.

Salvo wrote:
I think both the poly and mono panels have similar low irradiance efficiencies. The mono has a good spec, while the poly has missing I-V curves. I would decide at the shop. See which panel is better made. How much does the frame flex? Take a multimeter along. Measure Isc (if they allow).

Sal

[HiTech]

Getting into building sized systems at this point. Anything to beg, borrow or steal from off grid residential systems?

Jim

[pianotuna]

Hi CA T,

Not quite--a fold up "tail" on the back may be an option. I've grown concerned about a controller for six panels too--it seems that for 12 volt that is going to be tough to find. Even four panels are hard.

CA Traveler wrote:
With 28' rig and 6 panels the only real option is to mount them above the ACs. Don't know Dons roof layout but likely this is the only option even for 4 panels.

[CA_Traveler]

Of course with one controller his options are 4 panels or 6 panels and 24V, which will involve additional equipment. So the only real option for 6 panels is 2 controllers.

[pianotuna]

Hi Mr Wiz,

You are quite right about that.

[CA_Traveler]

With 28' rig and 6 panels the only real option is to mount them above the ACs. Don't know Dons roof layout but likely this is the only option even for 4 panels.

[pianotuna]

Hi smk,

I'm at 100 inches wide (2.5 meters) and 28'5" (8.7 meters) long. (roof is, of course, shorter).