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.

[2oldman]

Without regard to your budget, just your needs, I'd recommend this controller:

Outback 60a

The other controller you mentioned looks similar and I'm sure would be fine.

This is one good controller - fully programmable, 3 stage, MPPT with equalization, it allows up to 150vdc input and will handle 12 through 60v battery banks. Hard to miss with this one. Handles my 800+ watts with ease. You can wire your panels in series - no problem. With that much wattage I personally think series wiring will be much easier for you.

I don't know if any panels are better in low light - and if they were I doubt it would be a whole lot of difference.

[hmknightnc]

That midnight controller looks like it would handle 4 panels but not going to do the 6. The 4 could be in series if wanted to reduce line losses.

Got to agree with BFL though. For the adventure your are planning my vote is get the Honda 2k and store inside to avoid the extreme cold temperature starting issues you are worried about.

[BFL13]

I have decided to spend PT's money "my way"

He is looking at 4 24s and MPPT, which will get him 60a approx.
Comparing this to getting 60a with PWM and looking at total panel square footage and costs.

I get my panel sizes and cost here for an example (panel sizes are many-shaped depending on some whim it seems for length and width proportions)

http://www.windturbine.ca/sun_panels.html

MPPT- using 230w panels above, 4 would be 70.2 square feet
PWM- using 120w panels above, 8 would be 77.9 square feet

Each will do 60a and cost about the same at
8 x 129 = $1,032
4 x $248= $ 992

Controller amps sizing with 20% margin over expected amps (Isc for the PWM case) means eg, four 20a controllers for the eight 120s in pairs, all controllers then in parallel on the batteries (never mind, this is just for a costing)--at $39 each that is $156 for controllers

How much for an MPPT controller that can handle 60a expected plus 20%?
Yipes!

So it is
-$1,032 plus $156 = $1,188, vs

- $992 plus YIPES = ??? $1,500 ???

So for the same amps, but to save 8 square feet of roof (4 x2?)
It will cost another ?? $300 ?? Doesn't seem way too bad, I don't know.

Now we have at least another $1,200 in the budget. Run do not walk, and get the dad-blamed Honda 2000 and stop fooling around I say!!! 🙂

[CA_Traveler]

The Classic 150 has a 162V (150 + 12 for the battery) limit. 4 panels in series would likely be to close. But 2x2 would work and also be under the 80A limit.

[pianotuna]

Hi,

This controller may be the one I need:

midnite classic

I may be wrong about that. I have difficulty understanding their input voltage table.

[pianotuna]

Hi CA Traveler,

There is a limit to where everything can be "put". I already have one "corner" which was (fortunately) wasted space. Now I can use the space above it for a 2nd controller (maybe), or I can go for one much larger controller and "do everything". I know there are controllers with dual outputs. Is there one with dual inputs?

CA Traveler wrote:

I'll only be adding one controller--due to space considerations

This seems inconsistent with 6 panels. Care to explain?

Morningstar is limited to 3 of your panels. Outback and Midnight have 80A+ controllers so 4 panels could be used.

You could use the Morningstar with a 24V battery bank. :B

[CA_Traveler]

I'll only be adding one controller--due to space considerations

This seems inconsistent with 6 panels. Care to explain?

Morningstar is limited to 3 of your panels. Outback and Midnight have 80A+ controllers so 4 panels could be used.

You could use the Morningstar with a 24V battery bank. :B

[pianotuna]

Hi hmknightnc,

No, there is no room for more battery bank.

I like morningstar too--but I'll only be adding one controller--due to space considerations.

hmknightnc wrote:
Wow PT. That's a lot of solar. Since I'm a Morningstar fan it would take 2 45 amp if going with 4 panels or 2 60 amp if going with 6 panels. Are you planning to increase your battery bank size as well?

[pianotuna]

Hi Jim,

I'd love to do that--but it becomes a width issue. I'm at 2.5 meters or 8'4" much wider and I'm not "legal".

HiTech wrote:
The Unisolars might be nice side mount strips. Probably too long for rear mount. If you are going MPPT in a single controller with mixed panel types and orientations, it is critical to get one that can find multiple local max output voltages, and pick the highest output of them. Otherwise you could end up with less yield than PWM in some situations.

Jim

[hmknightnc]

Wow PT. That's a lot of solar. Since I'm a Morningstar fan it would take 2 45 amp if going with 4 panels or 2 60 amp if going with 6 panels. Are you planning to increase your battery bank size as well?

[HiTech]

The Unisolars might be nice side mount strips. Probably too long for rear mount. If you are going MPPT in a single controller with mixed panel types and orientations, it is critical to get one that can find multiple local max output voltages, and pick the highest output of them. Otherwise you could end up with less yield than PWM in some situations.

Jim