FAQs for going solar

raztec wrote:
Hello

I know there are a lot of posts on the topic of solar already, and I don't want to post yet another list of newbie questions about all the components I need etc. So I was wondering if someone's compiled a FAQ for going solar?

Thanks
Raz

I think you will find much of what you need here:
Boondocking Resources Sticky

Read through these threads and decide where you fit in to cover your needs and style:

> Forum Members Solar Installations With Pics

Chandalen wrote:
Ski: I started with the Renogy 200w panel kit. The controller with the kit is ok.. at best. After changing to a TS-45 I noticed a huge improvement. I have since expanded to 5 panels.

I only got the panels and assembled everything else myself including a Solar30 controller for $30. I am already dissatified with that as it is single setting that I have to manually switch depending on whether I am on shore power or dry camping. I ordered the other controller that Renogy uses, the Viewstar VS3024 which is far more capable with custom settings for float, bulk and equalizing. I will probably add two more panels later. If the OP can find a kit with the Viewstar, I would recommend that over the cheaper kit.

Ski: I started with the Renogy 200w panel kit. The controller with the kit is ok.. at best. After changing to a TS-45 I noticed a huge improvement. I have since expanded to 5 panels.

OP:
You are gonna see a lot of opinions on MPPT vs PWM. You need to see what your end game is (right now). Controllers are based on amp's they can handle, so skimping and getting a small low amp controller will severly limit expansion. Personally I prefer PWM for small systems.

Cable size is VERY important. Hell somone just posted they are using 1/0 wire from panels to controller. I drilled a hole in the camper roof to route the wires as short as possible. Some people would never do this.

Read the general guides you will find. If you don't understand some aspects, search for clairification or ask here!

Lastly, if you get an inverter make SURE its a PSW (Pure Sine wave) not an off the shelf wal-mart inverter.

MUCH GOOD INFO HERE.



And the spreadsheet referenced above is great for sizing a system. Even if you don't have something specific on it, add anything you might reasonably expect to use/add to the power consumption in the future.

Here is a simple flow chart.

Budget-->Energy Audit-->Battery bank size-->number of watts-->PWM or MPPT. What ever type of controller is chosen, make sure it has adjustable set points and a temperature probe that is on the battery.

If you use solar as a battery charger, one rule of thumb is between 60 and 150 watts of panels per 100 amp-hours of storage. The smaller the battery bank the higher the wattage needed (per 100 amp-hours). Here is a link to the rather special spreadsheet which includes an energy audit, that N8GS has created to help size solar battery charging systems!
solar spreadsheet by N8GS

If you full time or use an inverter lots, then populate the entire unshaded area of the roof with panels. I'm considering replacing my awning with solar panels.

For a nice explanation of solar, try this link:
Golden rules of solar

Google 'solar for rv'

My feeling is that after over 18 months of researching, some of the info makes it seem harder than it really is. I like the Renogy 200 or 400 watt starter kits that have everything you need. The biggest issue for me was how to get the cable from the panels to the controller. The refrigerator vent was at the opposite end of the trailer so I didn't care for that solution as it involved too much cable and voltage drop. I finally found a good description (somewhere) of using a holding tank vent and that took care of my biggest problem. There are lots of solar panel install threads so just find one you like that answers most of your questions.
A DIY Solar Install
People agonize over how much solar, whether to use PWM or MPPT controllers, what size cable, parallel or series wiring. You can just start simple and change later. I went with two 100w panels and a 30a PWM controller that can support two more panels.