Solar Power Systems

[bigbluedoggy]

I bet someone here can help with this one! I want to make our camp a greener place and I've been scouring the net for a solar power system to use. I was wondering if someone here has a lead on folks who put together packages for things like this or can at least answer some questions. I can find all the parts, but I would like to consult with someone who knows more about it before I commit to a purchase. We don't need a lot of power, but I don't want to get something that has to run at full tilt boogie to keep up! I'd prefer a little headroom! Anyone got suggestions or info to offer on sources? Thanks!!!

Doggy *woof woof*

[EspressoDude]

sample solar system

one 40 watt panel $250.00
two gell cell batts $250.00
circuit breakers $ 50.00

$550.00

now you can have 2 small fans in your tent plus 2 10watt flourescent lights for 8hrs AND two 10 watt black lights for 3 - 4 hours....

sound daytime add another panel total $800.00

sound nighttime add another panel (now 3) plus 2 batteries(now 4) total $1350.00



thats a lot greener in someone else's pocket. not bad for one week a year.

ps: I did step 1

[bigbluedoggy]

Thanks EspressoDude!
I understand the gist of it, but I am looking for more specifics: how many batteries can I put on a single charge controller, how many panels, etc. Costco sells a pretty neat little package (sans battery) for 1599, but I know the parts are probably available for cheaper like you indicated and I am looking for something that would give us, say: 2- 15 Amp 110v circuits by day and maybe a little less at night (well after midnite anyway). I'd love to find a webpage with loads and specifics and stuff.

If things work out as we hope, our camp may be across from yours again on 3:00 plaza! See you out there one way or another! Thanks!

I also now realize I posted in the wrong area of the forum and should probably have done this in the preparation threads... apologies to the powers that be.

Doggy

[gyre]

http://www.sunelectrical.com/

http://www.affordable-solar.com/solar.p ... 2421239512

http://www.kyocerasolar.com/

Used industrial panels are available too.

[bigbluedoggy]

Thank you so much!!!

[gyre]

If I can help with minimizing consumption, let me know.
That's the first step.
You're looking for a lot of power.

I want to put solar on an rv and I don't plan on that much, even for year round use.
But I'm guessing you know this isn't a cost effective approach, for just one week.

[frenchblue1]

try the contractor lead list for solar generations
http://www.solargenerations.com
They are providing solar assistance at Black Rock and then I believe the town of Gerlach is going to be gifted a system for the schools.

[EspressoDude]

Think of batteries as storage devices (like a lake) batteries are rated in amp hours say 80 amp hours.

12volt battery (100%useability assumed) x 80 amp hours = 12 x 80 = 960 watt hours (amp x volts = watts) That is the size of the lake.

One 15 amp 120v circuit fully loaded is 1800 watts, (15amps x 120v)


960watt hour/1800watt = about 1/2 hour use, likely to be more like 15 minutes because of inefficiency.

One40 watt solar panel (12v nominal) puts out 3.3 amps in direct sun perfectly oriented at the sun and no dust on it.

Assume 12 hours direct sun. 40watt x 12 hours = 480 watt hours
into the batteries. this fills the lake.

Two solar panels (2 x 480 = 960) will take all day to recharge the battery that the load drained out of the battery in 15 - 30 minutes.

Bottom line.....minimize loads..

[bigbluedoggy]

LOL, OK... I get it... I should stop being such a power hog! So rather than trying to make the whole camp solar I think I will opt to power a few elements and still bring the small geni for peak use times. I realize the solar way is a high investment, low return option, but I would like to feel a little better about my carbon footprint and ease my consumerism conscience a bit. Nevermind the probably good sized amount of natural resources used in the manufacture of the components designed to help save the planet... is there a win win scenario here? Yes, I know... go live in a cave. Thanks to all for the links and tech info! It's been a very illuminating day or two! EspressoDude, thanks especially for taking the time to give the tech specs! Greatly appreciated!

Doggy *woof woof*

[gyre]

Another option is fuel cell generators.
Some are technically batteries though.
I don't know the cost on these, but I'm thinking not cheap.
They are supposed to be quiet and reliable.
I like the ones that run on kerosene or diesel.

Thermo King has an interesting diesel unit that runs power and a heat pump for ac or cooling.
That would be great for an rv.
It simply uses a very stable small engine.
Around $7000.

I want one of these.
http://www.fischerpanda.com/

[EB]

Bigbluedoggy,

Just a little friendly devil's advocacy here...

Don't forget, there's been years where it's been cloudy and rainy on the playa. Might be a huge bummer to sink a bunch of dough into a solar system only to have the sun not cooperate. With a generator, you don't have to worry about it.

[unjonharley]

My camp is used for eating, resting, bath and sleep.. Just don't need that much light.. Do the camp work in the day light, so only a LED head lamp is needed for bed time.. My ride has some small solar panels and a peddled generator.. This is for sound.. Left over juice from the day can be used for a 32 LED light, razor and camera.. Put the 32 light 7 feet in the air you can see well enough to set a camp..
There will be a passive solar air mover (no moving parts) to take the hot air out of the van..

[gyre]

How does that passive unit work?
Stack vent?

I think heat venting on cars and trucks is a terrific place for solar.
A few cars come with it.
You don't need a battery and only enough control to protect the motor.
No sun, no fan.
No sun, no heat load.
They make cheapos and you can make a good one for $100-200.

[MozyBonz]

This is cool reading this thread and watching NASA deploying a solar panel on the space station at the same time.

[unjonharley]

How does that passive unit work?
Stack vent?

I think heat venting on cars and trucks is a terrific place for solar.
A few cars come with it.
You don't need a battery and only enough control to protect the motor.
No sun, no fan.
No sun, no heat load.
They make cheapos and you can make a good one for $100-200.

\/
Some rigid but flexable plastic sheet. One section of stove pipe.. Inclose the pipe in the plastic, Close the top and bottom the plastic tube.. Connect the stove pipe to a car window.. (a little card board or sheet metal work here) Let the sun shin in.. AS the sun heats the inside of the pastic tube the black stove pipe absorbs the heat.. The heated air inside of the stovepipe will rise and be replaced by the air inside the car.. Do not vent for fresh air.. THe air inside the car is expanded and at the top of the car.. The passive solar unit will keep moving the expanded air out..

[gyre]

Nice photo.

I thought I had it, but I got lost somewhere.
There is no open vent to the outside?
Is it powered by heat from inside or sun hitting the pipe?
Is one inside the other?
I gather it acts as a radiator to dump heat?

[unjonharley]

Nice photo.

I thought I had it, but I got lost somewhere.
There is no open vent to the outside?
Is it powered by heat from inside or sun hitting the pipe?
Is one inside the other?
I gather it acts as a radiator to dump heat?

\/
Open vent is through the top of a slightly lowered window.. You will have to build a (cardboard or sheet metal) rectangle to round duct... From window to stove pipe.. The plastic must be sealed around the pipe.. This lets the suns heat the area between the stovepipe and outer plastic.. The plastic tube is sealed top and bottom to force the heat to be abaorbed through the black pipe.. The basic thermal dynamists happens when you roll the window down on a hot car.. By heating the black pipe you are speeding the prosses up.. By surrounding the stovepipe you capture the heat from the sun.. The heat expands the in the closed area.. The black pipe surface absorbs the heat to the inside of the pipe..(Heat always go's up).. The heat inside the stovepipe will rise up and out of the top.. The vented air is replaced by air from inside of the car.. By opening the car window slightly the hotest air will be drawen off and replace the exhusted air.. As long as the sun is heating this keeps working..

[gyre]

Is the stovepipe open to vent air out of the car?
Is the plastic clear?
If so, I've got it.
Classic stack vent, like a good attic system.
But it normally requires an inlet, even if it is small.
And it works better the lower the inlet is relative to the top of the pipe.
Good thinking.
Did you find a big increase with the plastic around the pipe?

[unjonharley]

Is the stovepipe open to vent air out of the car?
Is the plastic clear?
If so, I've got it.
Classic stack vent, like a good attic system.
But it normally requires an inlet, even if it is small.
And it works better the lower the inlet is relative to the top of the pipe.
Good thinking.
Did you find a big increase with the plastic around the pipe?

\/
Stove pipe is open at the bottom through the rectangle (that fits the window opening) to the round to fit the bottom of the stovepipe..

The plastic should be clear..

The inlet is control by the size of the lowered windows rectangle duct..

I used two sewing hoops (from goodwill) to form the plastic into a tube.. then cut two aluminum disc with holes to acomadate the stovepipe

[gyre]

Got it.
That is using the stack effect.
It takes advantage of the pressure variance from one level of air to another.
Technically hot air rises, not heat.
The pressure difference is the reason.

By inlet, I meant a fresh air intake into the car.
Ideally, it would be as low as possible and in a position to cross the car.
Even crossing the roof will take heat away from the car.

That's why you can have all the windows open and no air.
Pop a sunroof and the hot air flows up.
I'm thinking seriously of chopping a hole in the roof of my car for one of those metal vents that pop up.
And then a solar powered fan in it.
The metal is nice because you can leave them open while the car is locked.

That's great thinking, Unjon.

[unjonharley]

Sorry about being condescending with the heat and hot air..

I'm instaling two maybe three of these vents on my RV/home.. Also adding those solar car window fans in the exhust tube..

[gyre]

Condescending?
Is that a heat and ventilation pun?

I was thinking of using electronic muffin fans.
Let me know if you find something better.
There are two styles, generally.
Very quiet and high flow.
They tend to be efficient.

[trilobyte]

BigBlueDoggy, don't let the earlier responses get you down - it's GREAT info!

Like they said, the key thing you want to do is minimize your usage. Replace incandescent lights with fluorescent, or even better with LED lighting. Look for other ways to trim your wattage/consumption. If you're doing sound, some are more energy efficient than others - it might make sense to replace that old amp you've been taking to the playa with something newer that consumes less power.

Yeah, solar is horribly expensive. Upfront, the costs are prohibitively high, but remember that you'll save it on the back end, since the gear will last you a while (if taken care of properly), and you'll never have to spend money on gas and oil and all that.

Good luck!

~Trilo~

[bigbluedoggy]

Thanks Trilo! I know better than to wear feelings on sleeve in here... lol I think there are many valid points made, and some excellent links and advice. Between this and a few other threads I have decided on a number of changes in our camp infrastructure... new evap design, changing light fixtures... other things to save power and be greener. I appreciate all of the great info from many people. Thanks!!! Come by Destiny Lounge and see!!!

[gyre]

It looks like the Sun Electrical link I posted is not the one I was looking for.
There was a company called Sunelco that may have been bought by Kyocera.
They had wonderful instructions.
There is at least one book on the subject too.
Real Goods carries a lot of stuff, including 12 volt cfls.

Fluorescents will be more efficient than LEDs for any substantial lighting.
If I can help you find good fixtures, let me know.
There are usa made ballasts.
I found a large selection of european dc lights, but expensive.
Lowe's carries a cheapo 13 watt made in china, intended as a car work and access light. About $20.
An LED may work better for spots or any point sourced light.
They may work out more efficient for colored lights and uv.
A 1 watt luxeon is good for about 25 lumens.
LEDs are compact and very good in cold, bad in heat.
If you can get by with 1 and 3 watt LEDs, they may be a good way to go for tent lights.
My cfls are doing 53 lumens/watt.
A PL-S has much higher efficiency.
If you can use amber, low pressure sodium is about 133 lumens/watt.
Maybe better, that's from memory.

Enclosed fluorescents will be more efficient at night due to cold.
The colder the better for LEDs.

[photon]

Try Sierra Solar Systems! www.sierrasolar.com They live with the equipment they sell and know what does and what does not work. Beware of some of the info given out on these pages. There is no way that you will get 12 hours of sun out there. More like 6 full sun hours at 1000 watts per square meter once trhe dust is taken into account. This means a 40 watt panel will put out about 240 watt hours a day. Then after taking all the system inefficiencies into account you should only count on about 65%-70% of that. Batteries should only be rated to supply 80% of their capacity, this is one deep cycle. Going beyond that will severly reduce it's lifetime. Also, stay away from gel batteries unless you have money to burn, need to store them sideways or have a really difficult time keeping them topped off with distilled water every few months of use.
Again, try Sierra Solar Systems.