How much solar power required?

pianotuna wrote:
Hi recyler,

How the heck did you squeeze 1000 watts onto a truck camper?

is just a design so far... my camper only has two 14x14 vents and the refer vent is only 14x6 and the stack vent so is alot of open space on the roof..the mounts would bolt to the sides of the roof..with the grape solar 100 watt panels I spec'ed I could group five together over the cab over alone...I have since decided that big of a system is not needed on this unit so when I get that far will only go to 600 watts max...and was going to eliminate the rear vent plus looks were secondary with the first design..

Hi recyler,

How the heck did you squeeze 1000 watts onto a truck camper?

is interesting question.. i am building my t/c to be self sufficent and looked into that..the battery bank and solar needed to run the a/c is huge..the system i designed for mine was 1,000 watts of panels and 3 12v floor sweeper batteries and it wouldn't able to deal with the load of a t/c a/c unit running constantly..this was enough to power the refer, water heater, lights and fans for the swamp cooler though even on cloudy days..

double post :o

TheLostOne wrote:
How much solar power is required to be self sustainable.

In order to answer this question you need to create a power budget based on your personal real-world energy usage goals...
Multiply the amount of time (in hours) you would like to use each item in your camper (lights, water pump, fridge, TV, A/C, microwave, laptop, cell phone charger, radio, etc...) by the number of amps it draws and then add the results for all of the items together... this will give you a starting point for how many amp-hours you are likely to use each day? Oh, and don't forget all the vAMPire loads like the CO & LPG detectors.
Once you are armed with this info, the folks here can help you determine how much solar you should plan for.

Based on your desire to be "self sustainable" (I am assuming that you mean not running a generator or charging from the truck's alternator), I would guestimate a starting point of 200W of solar and 200A/h of battery as the minimum you would find to be acceptable. With this much storage and charge capability you should easily be able to watch TV, keep lights on, use the water pump as much as you want, and operate the fridge (running on LPG of course) and get through the occasional cloudy day without depleting your battery.

If you're actually planning to run the air conditioner from your solar/battery/inverter system, you will need much more battery capacity and a lot more solar... plus a large power-hungry inverter. That said, if you have the desire, budget and space it can be done!

By way of example; I have 300A/h of battery and 328W of solar and if the sun is shining I can easily cook a meal in the microwave or run the A/C for a couple hours every day. I don't need to depend on any other power source unless I want to run the A/C for a long period of time. If I take the A/C out of the equation, and run the fridge on LPG, what I have fits my idea of "self sustainable". YMMV.

Cheers
-Mark

TV, all you need is about 50 watts or so.
Fridge, use it on propane, the same 50 watt panel that runs the TV will more than cover the 12v necessary for the fridge. If, for some strange reason, you have a residential electric refrigerator in your TC it will probably use somewhere around 2 kWh per day. This would require 400 to 750 watts depending on where in the country you were and what the weather was like.
Air Conditioning, not going to happen. If you had a huge class A and filled the whole roof with panels and the entire basement with batteries you could do it but just barely.

I just installed 300W of solar panels on my TC and I have been very happy with the result. I have two group 27 AGM batteries with a 1750 W inverter. We have been discharging to about 80% over night and by noon the batteries are once again fully charged. DW is happy because she can now run her curling iron, hair drier and a small blender for protein shakes. We have also been able to run two laptop computers during the daylight hours and not discharge the batteries at all.
Here are some links of places I used to do the research I also got a lot of help from another forum member 6 tons.
Here are some of the places I did my research on the system I installed.
http://www.amsolar.com/
http://www.solarrvpanels.com/index.php/determinine-how-many-solar-panels-you-need-doing-the-math/
http://www.where-rv-now.com/Notes/Solar/index.php#Calculator
http://www.windsun.com/Photovolaic_Systems/RV_Systems.htm
I finally bought a complete system from AM Solar, did the install myself. What I liked about their system is that everything that was required to install the system was included in the kit.

Hi,

Running the air conditioner given the limited space on a truck camper may be impossible unless hauling a "power trailer" with a magnificent battery bank and 1500 watts of panels.

It is cheaper to go to an inexpensive campground than to run a generator. http://freecampsites.net/

2oldman wrote:
Solar doesn't "run" things.

Yes, it really can and does.

We have 120 watts fixed on the roof. As we usually operate in sunny, beach conditions. with three type 29 AGM batteries the system is fairly self sustaininng. The system includes, lights, fridge electrics (propane is primary fridge source},TV( the satellite receiver operates from a 400 watt inverter). We charge the cell phones and the laptop batteries as needed with the inverter . If there is any overcast this system is not adequate. I'm considering doubling it to 240 watts or more. We have a built in propane generator which brings the batteries up well when needed. We also use the generator for A/C, coffee maker, microwave and electric frypan.

The 12volt system will not operate heating appliances. A rule of thumb is to monitor the battery voltage when it drops to 12.2 volts, roughly half of capicity, it is time to recharge. Allowing them to go below 12.2 volts will shorten the useful life quickly. I would say 120 watts would be the bare minimium needed.