boondocking and batteries

cruiseruser wrote:
We were newbies to boondocking and I had a large double slide truck camper with two 12v batteries. We were constantly worried about not having enough power when out and about for any length of time. We always would immediately turn off all lights, pumps, tv, etc.
It came time to replace the batteries. We were told to cycle the batteries down to nothing and then fully recharge. We turned on EVERYTHING that had any current going to it (lights,frig,inverter,two fans,tv,stereo) you name it.

SEVEN DAYS LATER... everything was still running!! Never worried about power again!!
Keep the genny, just in case!

Good luck. Worry less-enjoy more!!!!

We were always told to discharge lead acid batteries to no more than 50% of capacity or damage would result..??

tonymull wrote:
LED lights, AA powered CO2 detector and smoke alarm. Don't run the furnace except for a few minutes to warm up in the morning and then your only drain will be the small amount the refrigerator fan uses. If you need a microwave, hair dryer,and coffee maker....I wonder why you are camping at all.

wow,who said anything about all that.i know i said all opinions were appreciated but thats uncalled for.fyi when i camp i dont have a microwave,tv,stereo and i'm mostly bald.i need battery power to run led lights mostly,and the water pump.if you read my original post you'd have noticed i never had a battery.your post has no info that i was looking for at all.

Besides my Monthly trips, I used to spend a week dry camping in the summer.

Your 12v power draw will usually go something like this:
- Furnace
- Whatever your plugging in
- Lights
- Water pump
- Parasitic loads (smoke/leak detector, exc.)

We found that if we just used the furnace for a while before going to bed and a while just after getting up we could save a bunch of power.

I used to plug in an inverter to charge an old power hungry laptop. I now have a less power hungry one and a DC/DC converter to charge it.

Old style CAR bulbs use an ENORMOUS amount of electricity. Back in the day I designed and built my own 1/2W LED replacements. These days there are 1W & 2W commercial models that put out a lot of light!! With LED's if you just turn on the ones that you need when you need them, they don't draw much power overall.

Personally I don't worry to much about the parasitic loads or the water pump, its not like we're pumping water all day+night.

Here's what I recommend. Get yourself a Digital Volt Meter. These can be had for 3-7$ at Harbor Freight or many home improvement or hardware stores.

There are a number of lead acid battery voltage=%capacity used charts on the internet, find one and copy the numbers down for reference.

Go camping in your TC just like you would normally but this time measure the battery voltage when you start camping, then just before bedtime and when you get up in the AM and finally after 24hrs of camping.

It is recommended that lead acid batteries are only discharged 30-50%. So your first reading (when you got there) hopefully verified that you have a mostly full battery. The measurement just before bedtime hopefully showed that you have enough energy to make it through the night and when you measured in the AM it hopefully not only confirmed that you had enough energy, but hopefully enough to last the full 24hrs after starting.

The idea here is that worse case your battery voltage should never drop below +12.1V. (50% charge) You may of dipped down to +12.1V fairly quickly or after 24hrs not at all. Now that you have an idea of your energy use you just have to ether add AH capacity so you can meet your total hours dry camping or use less power or add another power source to charge your batteries.

My 1st camper came with automotive bulbs and a type #24 battery. I could barely last 6pm-6am without starting my truck to recharge in the mornings.

LED lights, AA powered CO2 detector and smoke alarm. Don't run the furnace except for a few minutes to warm up in the morning and then your only drain will be the small amount the refrigerator fan uses. If you need a microwave, hair dryer,and coffee maker....I wonder why you are camping at all.

Step 1 when you get it is to upgrade to LED Lights, unless it has them already.

I'm running lights from www.ledtrailerlights.com as are a bunch of other members here.

Solar has one huge advantage, besides constantly charging the battery when the sun is out without making any noise.

The solar panels will shade the roof, so it will not be as hot inside!

SunElec.com has many 12 volt panels that can be teemed up with a PWM controller, and some home made mounts, UV rated #10 wire to bring the power from the roof down behind the refrigerator to the controller, then on to the battery.

The problem is your RV will typically use 35 amp hours daily to run the CO meter, propane leak detector and refrigerator. Most batteries are group 24 - 75 amp hours, or more likely group 27 or 31 at about 100 amp hours.

By installing a couple of 100 watt solar panels, you can put back about 60 - 80 amp hours daily, and quietly! Then you will not need as much battery capacity, as it will only be used in the night time to run the CO meter, propane detector, and refrigerator, along with a few lights. During the daylight hours, that 20 amp hours is made directly from the solar panels, and will not need to be stored.

Because you asked about batteries and a generator, I will give you information about that. 500 watts is pretty small capacity, and your stock 45 - 55 amp 'converter/charger' can use more than 500 watts. It can use between 600 and 900 watts, depending mainly how low the battery is. If you find that the battery is low, and the generator trips off due to being overloaded, you can start the truck, that will put 14 volts to the battery for a little while, then plug in the generator, it will charge at a much slower rate. After 10 minutes running the truck and generator, then you can shut off the truck, and the charge rate will be below 30 amps, (about 450 watts input to the charger) and will continue to run on the generator. After the battery is about 2/3 full, the charge rate will drop below 20 amps, and you could watch TV (a 100 watt load) at the same time the battery is charging.

Sometimes when I would run my generator, I would keep using the inverter, and run the TV from the inverter, and then be able to keep watching the show when the generator goes off. This might happen if I was cooking dinner with the microwave, or making coffee, and then run the generator for about 20 minutes to exercise it.

I have a 4,000 watt Onan generator and 70 amp charger hooked up to 4 golf cart batteries, so they have a capacity of 440 amp hours. My charger would only put out about 50 amps when the battery was less than 50% full, and only for about 15 minutes, then slowly taper to 30 amps after 60 minutes run time, as the battery filled up.

The best time to run the generator is in the morning for about 1 hour, and later in the afternoon for 1 hour. It is that first hour that the charger puts out the most amperage, then it tapers to almost nothing as the charger runs a second and third hour. To get from 35% full to 70% full might only take 60-75 minutes, but to get from 70% to 85% would take an hour or more. That last 15% can take all day, expensive and noisy when running a generator.


Good luck!

Fred.

I dry camp for 4 days every year in my 850. I have the fridge on gas and use the lights sparingly. (don't leave them on, don't use the outdoor lights, etc.) I've never had an issue with the battery.

I don't have a TC, but I do dry camp always. I also disappear for 2-3 weeks at a time on occasion.

The first thing I'd do is add another 12 volt battery, and probably get a little larger generator in consideration that solar isn't something you're interested in at this time. I am a fan of Champion generators, although most folks here on the Forum will recommend Honda or Yamaha.

I use a 1500/1200 Champion, very reasonable cost @ about $200, (Amazon) dependable, parts are easy to get & customer service is very good. A step up from there is the 2000 Inverter type @ about $375.( SuperGen)

TORKLIFT is well know here on the Forum & a well respected company. They have an undercarriage battery enclosure that fits on the frame of your truck, called "HiddenPower"

We had 2 golf cart batteries in our 26 ft 5er. We used lights sparingly.....but would run my cpap machine all night. It would go 2-3 days without using the generator. We bought portable battery lights for those times we wanted to read far into the night :) :)

We were newbies to boondocking and I had a large double slide truck camper with two 12v batteries. We were constantly worried about not having enough power when out and about for any length of time. We always would immediately turn off all lights, pumps, tv, etc.
It came time to replace the batteries. We were told to cycle the batteries down to nothing and then fully recharge. We turned on EVERYTHING that had any current going to it (lights,frig,inverter,two fans,tv,stereo) you name it.

SEVEN DAYS LATER... everything was still running!! Never worried about power again!!
Keep the genny, just in case!

Good luck. Worry less-enjoy more!!!!