Who knows solar power?

Alright guys we are getting ready to setup the pop up trailer for our actual use. One thing that the trailer has as a great advantage over a tent is the fact it has lights, a fridge and places to plug in other electronic items. This will be particularly nice next month as I will be heading up to the mining claim for a bit and this will just add a bit of comfort over my normal tent.

So I got thinking about it yesterday and thought it would be cool to setup a solar charging rig for the battery to help keep the power going. Anyone have any suggestions of a budget way of putting together a system for helping keep power going in the trailer? Electronics in the trailer will be limited (and obviously not all in use at the same time or constantly), a radio, possibly wire in a CB and scanner, a small fan to help move air and cool things down if need be, the interior lights, charge small device batteries and I may take a laptop to watch movies on and the like.

So anyone have any ideas? Good sources of information?

Stay away from the harbor freight, they are a pretty good waste of money unless you just want to power two compact florescent bulbs . For the panels you want higher wattage and monocrystalline for the best value. here is an ok deal for an example.

There are some good youtube videos that will link you to better sites. I think this was a good youtube video to start with

Adding another battery in parallel my be more cost effective. Your fridge will be the biggest draw- about 20 amps per 24 hour period. That is as much as you will get out of a 600 cca auto battery. Add one more of those batts and you will get 40 hours of run time plus plenty of juice for your ancillaries.

I bet you would pay more for a harbor freight solar charging system. Plus you have the hassle of setting it up. Plus if its cloudy you could be berkleyd.

Solar technology just isn't there yet, but it will be in time.

Food for thought...

rebelgtp wrote: Alright guys we are getting ready to setup the pop up trailer for our actual use. One thing that the trailer has as a great advantage over a tent is the fact it has lights, a fridge and places to plug in other electronic items. This will be particularly nice next month as I will be heading up to the mining claim for a bit and this will just add a bit of comfort over my normal tent. So I got thinking about it yesterday and thought it would be cool to setup a solar charging rig for the battery to help keep the power going. Anyone have any suggestions of a budget way of putting together a system for helping keep power going in the trailer? Electronics in the trailer will be limited (and obviously not all in use at the same time or constantly), a radio, possibly wire in a CB and scanner, a small fan to help move air and cool things down if need be, the interior lights, charge small device batteries and I may take a laptop to watch movies on and the like. So anyone have any ideas? Good sources of information?

If you think solar is not there yet.. you need to check out the marine stuff. There are plenty of sailboats out there using cells to keep the batteries topped up, even with fridges up and running

This is a good sum up, even if it pushes their product a bit

WestAdvisor Solar Panels

I guess some perspective is in order. At work we have whole roof systems on some of our buildings to supplement utility power. There isn't a system available that can power the 1500 amp average load needed for a research building and produce enough excess to store for use during the dark hours.

For a small load like a boat, I'm sure solar systems can generate enough power to store in batteries to cover the dark hours.

But to power a small rv for a weekend you can buy an extra $90 car battery versus spending $200 plus on a solar charging system for one battery.

I'm not saying it can't be done, just there are more cost effective ways to do it.

mad_machine wrote: If you think solar is not there yet.. you need to check out the marine stuff. There are plenty of sailboats out there using cells to keep the batteries topped up, even with fridges up and running This is a good sum up, even if it pushes their product a bit WestAdvisor Solar Panels

Somewhere out there is a floating generator, it's a small raft with a paddle wheel that turns a modified car alternator. That might be worth looking into if there's running water up there. You might even be able to build your own for cheap.

Curmudgeon wrote: Somewhere out there is a floating generator, it's a small raft with a paddle wheel that turns a modified car alternator. That might be worth looking into if there's running water up there. You might even be able to build your own for cheap.

Hmmm any ideas where I can learn more about such a rig?

There is actually a small river up at the claim and we normally setup camp next to that. There are a few spots where it narrows out and drops at the same point so the water moves faster in those locations.

We had actually talked about building a cabin up there and setting up a waterwheel generator type rig.

Remember guys I am not looking for enough power to run all day long. I am just looking for enough to maybe use the computer a couple hours at night to watch a movie. Check the radio periodically during the day maybe. Lights on for a couple hours at night. I will be out there for a minimum of a week, at times we can be up there for several weeks at a time.

If you have enough flow and fall, I'd be looking at micro hydro.

Something like this.

http://www.microhydropower.com/

Their smallest unit is $700. Or you can buy an extra car battery for $90. It's not as cool, but it will get the job done.

If you decide to go to an alternate source add up the wattage of everything you want to power up, compare it to what your battery will do and find a system that will regenerate 50% of that load. You should be fine with that, providing you charge your batteries between trips.

Good luck!

Toyman01 wrote: If you have enough flow and fall, I'd be looking at micro hydro. Something like this. http://www.microhydropower.com/

paranoid_android74 wrote: Or you can buy an extra car battery for $90. It's not as cool, but it will get the job done.

Where's the fun in that.

Besides, I'd want A/C and that's not happening with a couple of batteries.

There isn't any fun in that- I'm talking bang for the buck here.

With an inverter anything is possible for your AC needs. There should already be one in the RV to convert everything to 120 volts. Two batteries will give you enough capacity for a full weekend of AC fun- including a disco ball, strobe light and kegerator.

I'm not trying to be a downer here, I do this for a living. If you want bang for the buck this is it.

Toyman01 wrote:

paranoid_android74 wrote: Or you can buy an extra car battery for $90. It's not as cool, but it will get the job done.

Where's the fun in that. Besides, I'd want A/C and that's not happening with a couple of batteries.

Toyman01 wrote: If you have enough flow and fall, I'd be looking at micro hydro. Something like this. http://www.microhydropower.com/

See now that will be a good idea for the cabin once we get it up.

You are absolutely right! If you are looking for a longer term permanent installation alternative sources are the way to go.

rebelgtp wrote:

Toyman01 wrote: If you have enough flow and fall, I'd be looking at micro hydro. Something like this. http://www.microhydropower.com/

See now that will be a good idea for the cabin once we get it up.

In reply to paranoid_android74:

I think we had a miscommunication. A/C as in air conditioning. I hate to sweat while I'm sleeping.

A 12000btu A/C, running on inverter power, is going to draw about 130 amps off the batteries.

A pair of 6V golf cart batteries, about the most cost effective for high capacity batteries, will supply 75 amps at 12v for 122 minutes. So that would power my A/C for about 30 minutes. Figuring a 30% duty cycle on the A/C to keep the camper at 72 degrees, I would only need 134 batteries to make it through the weekend. If I cut the A/C size in half, I would still need a truck load of batteries to keep my fat ass cool. Those 134 batteries would set me back about $13,000.00. All the sudden micro hydro isn't so expensive.

jere wrote: Stay away from the harbor freight, they are a pretty good waste of money unless you just want to power two compact florescent bulbs . For the panels you want higher wattage and monocrystalline for the best value. here is an ok deal for an example.

I have 3 of those DMSolar 145W panels in my shop right now. I haven't set them up yet secondary to excess project syndrome, but they are ready to go. They were $140/ea delivered when I bought them. I see the price went up. I spoke with their "tech support" guy who was very knowledgeable.

Check out this link. http://www.mdpub.com/SolarPanel/ It is very useful. This guy built solar panels himself on the cheap, he also built a wind generator. You can see the wind generator at this link. http://www.mdpub.com/Wind_Turbine/index.html.

Oh he also built a biomass gasifier... http://www.mdpub.com/gasifier/index.html

In reply to Dr. Hess:

Cool, I was looking at those and some others that are discontinued now. Report back if you ever get them up and running.

I thought there was something funny with the price since I last saw that page too.

drsmooth wrote: Check out this link. http://www.mdpub.com/SolarPanel/ It is very useful. This guy built solar panels himself on the cheap, he also built a wind generator. You can see the wind generator at this link. http://www.mdpub.com/Wind_Turbine/index.html. Oh he also built a biomass gasifier... http://www.mdpub.com/gasifier/index.html

I have heard that the homemade panels have longevity issues or service issues something like that. The factory enclosed panels aren't supposed to have the problem. Maybe someone else can chime in on that?

rebelgtp wrote:

Curmudgeon wrote: Somewhere out there is a floating generator, it's a small raft with a paddle wheel that turns a modified car alternator. That might be worth looking into if there's running water up there. You might even be able to build your own for cheap.

Hmmm any ideas where I can learn more about such a rig? There is actually a small river up at the claim and we normally setup camp next to that. There are a few spots where it narrows out and drops at the same point so the water moves faster in those locations. We had actually talked about building a cabin up there and setting up a waterwheel generator type rig. Remember guys I am not looking for enough power to run all day long. I am just looking for enough to maybe use the computer a couple hours at night to watch a movie. Check the radio periodically during the day maybe. Lights on for a couple hours at night. I will be out there for a minimum of a week, at times we can be up there for several weeks at a time.

Here's one which has the wheel mounted semi permanently:

http://www.wildwaterpower.com/

It would not be difficult to make a 'raft' from old plastic barrels etc. The best part of a mobile one would be that you could store it in the cabin when you aren't there.

We use solar panels at our cabin because generators are loud and we are 8 miles from the grid. We have 280 watts (IIRC) of solar panels, a charge controller, batteries, and a 5000 watt inverter. We went for a week straight of just battery/solar power during the week of thanksgiving (read: less light). That's lots listening to the radio, half dozen compact fluorescent lights at night, a small LCD with a DirecTV box for at night, and charging cell phones.

I would get at least 100 watts of solar panel and have two batteries.

Toyman01 wrote: I think we had a miscommunication. A/C as in air conditioning. I hate to sweat while I'm sleeping. A 12000btu A/C, running on inverter power, is going to draw about 130 amps off the batteries.

For A/C you're going to need more than batteries. You'll need some sort of power generation in the 2KW range (maybe more). One of those ultra-quiet Honda generators, maybe.

This is one of the main things that keeps me away from a slide-in truck camper. While most have roof A/C, only the higher end models are equiped with generators, the others need a land connection or a generator sitting on the ground. If the thing can't be self-supporting, it's useless to me.

The paddle-wheel-alternator set-up is one of those ideas that sounds great in theory, not so much in practice when you start crunching numbers. Remember that discussion we had about wheel-mounted regeneration? Well, this is a similar principle with similar problems. Say we're loking for 2000W to run Toyman's A/C. At 12V that's over 166 amps. That's a big alternator which will need a decent amount of HP to turn it at full load. Hydro plants get this HP by using the pressure of the water intake at a higher elevation than the turbine ("head" as noted in the picture). Paddle wheels get this by using a big-ass freakin wheel.

Power is power and you don't get anything for "free".

Definitely nothing's free but in my case I wouldn't be running A/C. Maybe a small fan but that's about it. The small floating waterwheels will generate around 300 watts, that's enough to keep a bank of batteries charged. What makes it appealing to me vs solar is it works 24/7, meaning it'll charge the batteries at night too.

In reply to Curmudgeon:

True, although it does require some pretty specific conditions to work well, if at all. I know of few camp sites with a running stream that close and even fewer that would allow parking a small RV within reasonable extension cord (100' or less) away. And the stream needs to be deep enough and run fast enough as well as being secure enough that wandering drunks won't eff with it.

That's a lot of 'ifs'...

Quite right, I read that wrong- my bad!

You are absolutely right, a couple batteries won't handle an air conditioner for very long. And I sure wouldn't want to haul around the amount of batteries it would take!

As others stated already, I personally like the idea of the hydro systems if you can get one to work.

Toyman01 wrote: In reply to paranoid_android74: I think we had a miscommunication. A/C as in air conditioning. I hate to sweat while I'm sleeping. A 12000btu A/C, running on inverter power, is going to draw about 130 amps off the batteries. A pair of 6V golf cart batteries, about the most cost effective for high capacity batteries, will supply 75 amps at 12v for 122 minutes. So that would power my A/C for about 30 minutes. Figuring a 30% duty cycle on the A/C to keep the camper at 72 degrees, I would only need 134 batteries to make it through the weekend. If I cut the A/C size in half, I would still need a truck load of batteries to keep my fat ass cool. Those 134 batteries would set me back about $13,000.00. All the sudden micro hydro isn't so expensive.

mad_machine wrote: If you think solar is not there yet.....

solar will only be closer to 'there yet' imo when solar returns alot more power closer to whats needed to manufacture a panel.

thats when an exciting energy revolution will be close... ^_^