solar boost

I am always amazed at the SUCCESS stories about using solar panels...

I guess the way to success is to never get behind the charge curve on your battery bank. The solar panels then become a top-off source of charge energy for the battery bank when in high sun.

My daily schedule routine with all the 120VAC items using an Inverter and 12VDC items direct connected seems to draw around 22 AMPS (appx 300WATS) on my battery monitor meter 300WATTS between the 6PM and 11PM . This includes my parasitic drains. This equates to about 134AHs of battery drain over the one day/night run off the battery bank. This will drain down my 255AHs to its 50% charge state by 8AM the next morning. My trailer is equipped with LED lights and has smart mode charging capability for the batteries.

In my case having a single 120WATT Solar Panel or even two 120WATTS Solar Panels would get behind the battery charge curve real quick.

The 120WATT Panels will only provide 14.4VDC @ around 5AMPS each of DC Current in the high sun. The average time of high sun is around 6 hours and will only give you around 30Ahs of usable charge current per panel. Adding two of these bumps that up to 60AHs... Three panels makes it to around 90AHs. I am still behind the battery charge curve of not being able to put back into my batteries verses what I am taking out if I am using 132AHs a day.

When I get behind the charge curve I have to use my 2kW Generator to do the initial start-up BOOST Charging for around one hour using smart mode charging from my on-board converter/charger being run by my 2KW Generator. My 255AH battery banks initially jumps to around 52-53 AMPS Current demand from my converter/charger and this will slowly drop back to around 8amps of DC Current in about an hour run time as the battery banks starts taking on charge.

Once it gets past the high current demand then I can really use the solar panels to continue the battery bank re-charge to get to the 90% charge state or higher while still in high sun.

It all depends on how one likes to camp off the power grid and use the appliances and lights etc that they want to use. I must start out each day/night run with a good 90% charge state on my battery bank otherwise it goes dark on me around 10-11PM at night.

If I was just running LED lights and a occasional short term higher current draw then YES I can see where I would not get behind the battery charge curve and not have to re-charge in a few days... This just doesn't happen for us the way we camp with all of our toys... Ham Radio guys have to yak on the Radios too as well...

We basically look just like we do at a regular camp ground electric site with the exception of using the air conditioner and high wattage microwave. Just about everything else is up and running... When it gets cold at night this is an another story if the furnace has to run...

We have been very successful camping off the power grid with our 255AH battery bank and recharging each morning using our 2KW generator starting at 8AM when allowed to run it. Just now starting to think about adding solar panels to my POPUP trailer only to supplement the generator run times and hopefully reduce the amount of time I have to run my generator.

just my thoughts based on how we camp off the power grid and using solar panels to supplement the generator run times...

Roy Ken

We are very conservative in our power usage when boon docking (almost all of the time). LED lights, parasitic usage, sometimes plug in the laptop, maybe nightly heater usage (about 3.5A draw). About 200AH of battery. Need to charge every few days. 17' TT. Got tired of carrying around a generator so added 200W of solar - during high charge time around noon in the summer it's about 9A of charging.

Solar has no problem recharging normal loads by about 2PM the next afternoon without using a generator. If I go to an area that might have a lot of shade, and am there for more than 3 days, I still drag along the generator.

Now to add solar to our new to us 35' Toy Hauler. Even though it has a built-in generator, want to charge while we are away from the trailer during the day without running the generator.

Most batteries require 14.8 volts (Trojan batteries require) to fully charge your batteries. Most controllers will only get them to 14.4 or 80%full charge. Its not the panels its the preset controllers besides other things like wrong Gauge wire to batteries that waste the volts getting to batteries or charger.

If you are really interested in adding solar there is a lot to read and understand to buy a system that really will do all you need. A lot of cheap and expensive kits are available through dealers and on the net that wont do enough to charge the batteries full.

Buyer be aware. I started reading and learning all you need to install or have installed the right components to get the most out of you money. I asked like you on a site like this and someone sent me this mans address and now I understand it all. He is not selling anything at all, just a great guy trying to help educate us out here through his discovery with solar. link

http://handybobsolar.wordpress.com/the-rv-battery-charging-puzzle-2/

He has written so much about the subject and their is a lot of reading on his site, but like me you will become fully educated on how to live off the grid with 2 panels (320 watts) 2 batteries ( 6 volt) and never run out on power. Don't get ripped off by dealers selling you short on what you need. Be an educated buyer.

I got the Renogy 100w portable recently, then read some from Handy Bob. Now I would buy the suitcase panels without the charger and buy a better charger separately so I could install close to the battery bank and run longer cables from the panels for more effective charging.

You may find the handybob site wordy and it has some information that is dated at best.

Try these sites instead:


http://rvroadtrip.us/library/12v_system.php

http://rvroadtrip.us/library/solar_install.php

It use to be that the portables from the fancy outfits were so expensive that you could build your own cheaper. Now it's hard to beat the ones from solarblvd, windynation, eco-worthy, renogy and others.I saw a you tube of someone setting one up and it's pretty easy.

I make my own portables out of the larger higher voltage panels. They are 39x65 and weigh close to 50 pounds, One panel, one run of cables to the controller, around $400 for 16a+ of charging tracking the sun all day.

I would suggest one of those Renogy modules mounted to a lightweight stand and a cheap controller to start. You might consider replacing the battery you're using as it sounds like it has been abused and won't have the greatest service for your style of camping. A good replacement solution would be two Costco or Sam's Club 6V GC2 batteries. The price is close to one good 12V deep cycle battery and the 2 X 6V solution is a proven winner.

Good luck with your solar charging. If done right, there's no more need for a generator.