New Garage Build...Solar Panels?

[gto65goat]

I really enjoy this site.
What a great place to visit, and learn from the experiences of the members.
I'm planning a 33' wide X 24' deep X 17' tall Garage/Workshop w/ Divider Wall.
Have any members used Solar Energy Panels to provide Heat for the garage?
I'm in the detail design faze at the present, and would appreciate any advise.
What costs should I expect, if I follow through?

 

[Gregdoo]

There are three basic types of solar panels that can provide heat....

1) Photovoltaic - produce electricity - which could power an electric heater. In this application, probably not the best choice. Would need a lot and they are expensive.

2) Air warmer (not sure of the name) - has a dark surface and the sun heats the air in the sandwich between the glass and the dark surface. A fan pushes the air into the space to be heated. This would probably be the cheapest to construct and has the least complexity. Probably not extremely efficient, as the air wouldn't hold a lot of the solar energy. Would not do anything for you when the sun wasn't shining.

Another derivation is a trombe wall (see: http://en.wikipedia.org/wiki/Trombe_wall), which uses the thermal mass of a stone or concrete wall to collect the radient heat during the day and to in turn radiate the heat from the mass when the sun isn't shining. Would be simple and possibly very useful, if you have the ability to orient the building to use this method.

3) Hot water - Probably what you are thinking of. Sun heats water in panel. You could use hot water to heat concrete floor in tubes, (or from some other sort of hot water baseboard or radiator). Concrete mass would store some of the energy and provide a buffer for times the sun isn't directly shining on panels. Hot water could also be used with a heat exchanger and a fan to create hot air, or to raise the intake temperature for a conventional forced air furnace. Would probably want additional hot water storage capacity to provide a buffer for when the sun wasn't shining. Has more cost and complexity than option #2, with pipes, pumps and storage. Would want to mix glycol with the water to prevent water from freezing.

I don't have enough knowledge to discuss costs, but there are quite a few great books available at libraries or Internet sites that can help with the planning and determining what would work best in your situation. There are also solar energy tax credits available from the federal government in 2006 and 2007. Because of this, there will be quite a few contractors that will pop out of the woodwork claiming to "do solar". I'd do good research before contacting one, so I knew when I was being fed a line of BS.

 

[Just A Beginner]

I built a solar water system for my garden shed but it was no where near as big as your building volume.
It was 20 long by 14 wide by 12 high. I scrounged the following parts:

A used but excellent shape swimming pool pump.

10 fiberglass 55 gallon drums (from car wash places. The drums typically have liquid soap in them.

Used 1/4" thick plexiglass panels from a commercial window replacement store. Big car showrooms typically used the sheets.

I had to buy the copper pipe but got that from a
plumbing house with a builders discount.

Two Volkswagon radiator assemblies with electric fans.

Water flow is from the drums to the pump, up to the roof, through the heat exchangers built using the copper pipe and plexiglas, and then on to the Volkswagon radiators. Finally back to the drums.

With a 20 foot x 20 foot roof facing the sun, the shed would maintain 60 degrees at 10 degrees F
ambient temp.

Tom V.

 

[Gregdoo]

Tom,

You sound quite creative, I like your system. Were the 10 drums inside the shed, so that they would also give off heat, and maybe not freeze; or were they outside and painted black to help absorb solar energy? Also, you said you had copper pipe on the roof, I assume under the plexiglass. Did you paint the copper,and what diameter did you use? Did you use glycol in your system, or pure water?

Thanks. You have any pictures you could share?

 

[KingPerformance]

I am also very interested in this setup.

 

[kbs2244]

Do a search for something called Home Power Magazine. They are real fans of photo eletric, but they do have downloadable PDF files on the different kinds of sysstems and how they work, and the basics of how to build them.
Every issue has a featured install. I seem to remember one in New England where a guy put in a solar heated radient floor in his shop. Look in the back issues area. And look for any follow up stories. These thing can be complex, and it will take a season or two to work out the bugs.
Every site is different, but the major requirment is that one slope of the roof face the South. That is where the sun is in the winter.

 

[Kent in KC]

A solar air exchanger is clearly the cheapest/simplest/easiest to build and maintain. Essentially a 4'x8'x4" box on an exterior south wall. A bathroom fan blows cold air from near the floor out through the wall and up through the box which can have a maze-like channel to make the air move over the entire surface. Some use black screen wire stretched across the middle that heats up and transfers the heat to the air blowing through it. A vent near the top, like a laundry clothes dryer vent, lets the hot air back into the garage. The vent and fan both already have baffles so they prevent reverse flow at night, which would lose heat. I'm planning to use one on my new garage and I hear they do a surprisingly good job, when the sun shines. Otherwise a propane heater.

Radiant flooring of any kind, electric or hot water is expensive and best suited for applications where you want to keep it warm all the time (because the thermal mass of the floor takes a while to heat up and cool down). If you just want a warm garage when you are working out there, radiant flooring will waste your energy and money. It can be a great option for your house, however.

Photovoltaics are the most costly and inefficient form of solar. In a few years they will get better and cheaper.

 

[PAToyota]

Just heard a presentation from a guy doing research for PPG - they are looking at photovoltaic paints. Imagine an electric car that recharges by sitting out in the sun in the parking lot. Or that your house "re-charges" during the day while you are at work so that you have electricity for the lights and TV at night... Pretty interesting stuff.

 

[Red Green]

I brought this back to the top to see if any members had any more info about air exchangers or water systems? I already have the buildings I have a southern facing wall on my house and the detached garage has a southern facing roof. I am in Michigan also. Thanks for any help. I

 

[oldgoat]

I think that if a person has the right location the trombe wall is probably the easiest and effective way of getting heat. The version I remember from many years ago through I believe Popular Mechanics was the person built and small building in the yard with cut in half pop cans painted black. This heated up rocks in the building for a heat sink. They had ran duct work into the garage and had it set up with a blower on a thermostat that would shut off the blower when it got cooled down. Basically the maint. consisted of removing the rocks that broke apart from expansion and contraction.

 

[CaptainRay]

I've been thinking about Solar heating, found this on YouTube (a good source of info) This one is on pasive heating

Also thought wanted to find the best shop lighting for my dollar again YouTube a good source for research.

I have been experimenting with LED's for signs, which are fun to design and and make. Wanted to do something for LED’s to light bench work areas. I bought a bunch of LED’s through Ebay, very inexpensive. The signs are a fun project, did a lot of research for circuits etc.

This is an very informative videoe on the best shop lighting

The signs are a fun project, the desk lighting is something that might be powered by a solar panel you can get cheap from Harbor Freight.

Again YouTube is a good research center for anything you want to do...

This is an very informative videoe on shop lighting

 

[Lippyp]

I plan on making a hot air solar collector for my garage when (if, see my other thread!) we move to our new house. You can make a very cheap one using empty aluminium drink cans (good excuse to drink a lot of beer!) with holes punched in the bottoms and glued together into columns, painted matt black and sealed in a glass fronted box. The principle is air goes in the bottom from inside your building, gets heated up as it rises slowly through the columns and out at the top, can be assisted with a fan that could also be powerd by a small PV panel (12V PC fan works fine) and you can make them to whatever size you want. Loads of example on the web if you google solar hot air collector.

 

[drewski]

I have a solar greenhouse attached to my garage that I use to supply heat to a 15x30 finished room that my uses for her crafty ventures. I was fortunate that my shop faces due south.

The greenhouse is 10x15 with a dark color solid brick floor. On a 25-30 degree day it will heat the adjoining room to the mid 70's. I have a sliding glass door between the greenhouse and main shop to somewhat adjust the heat. Of course in the summer the greenhouse will badly overheat without some type of shading over the glass.

If I had more solar mass in the greenhouse it would probably help to maintain heat after the sun goes down. If I had it to do over, I would probably do things different, but it has performed well for the last 30 years.



Drew

 

[brianh]

I will be using hot water panels on mine, I am still in the process of finishing up the shop I put pex in the slab for the hot water.

A great resource for do it yourself is build it solar
http://www.builditsolar.com/

 

[joes169]

After doing a bunch of online research, I built 2 convective solar heater panels last winter. They fit inside the 12' x 12' OH door opening, and are hinged so I can swing them open to gain access to the door opening. Especially helpful in summer when they're not needed. I simply open the OH door in the morning, stick a box fan at the bottom opening on low, and close the door again at night. Honestly, it doesn't work near as well as I expected and I think the clear plastic is to blame. I'm sure it has alot to do with the fact that I didn't seal the clear sheets up well either. Here's inside & outside pics:

 

[SmokeyDP]

I built a solar water system for my garden shed but it was no where near as big as your building volume.
It was 20 long by 14 wide by 12 high. I scrounged the following parts:

A used but excellent shape swimming pool pump.

10 fiberglass 55 gallon drums (from car wash places. The drums typically have liquid soap in them.

Used 1/4" thick plexiglass panels from a commercial window replacement store. Big car showrooms typically used the sheets.

I had to buy the copper pipe but got that from a
plumbing house with a builders discount.

Two Volkswagon radiator assemblies with electric fans.

Water flow is from the drums to the pump, up to the roof, through the heat exchangers built using the copper pipe and plexiglas, and then on to the Volkswagon radiators. Finally back to the drums.

With a 20 foot x 20 foot roof facing the sun, the shed would maintain 60 degrees at 10 degrees F
ambient temp.

Tom V.

How much does the temp drop over the course of the night after the sun goes down? Does snow build up for long on the heater?

 

[rsanter]

look up on the net something called the 'half plan'
a guy set out to cut his utilities in half.
he built a system to feed warm/hot water into his hydronic floor system.
the same thing can be dont and route the water to a radiator that you use a fan to blow air over

bob

 

[Fleetwood]

When i was researching this i ran across this website http://tinyurl.com/howtosolarpanel when you go there there will be a short video explain what this guy has going on. Anyways he is a electrician that got shafted by the electric company, so he decided to build his own solar panels. I think at first he could build the panels for close to 200 a panel and he is claiming cheaper now. I don't know check it out might save you some money.

 

[Zick]

When i was researching this i ran across this website http://tinyurl.com/howtosolarpanel when you go there there will be a short video explain what this guy has going on. Anyways he is a electrician that got shafted by the electric company, so he decided to build his own solar panels. I think at first he could build the panels for close to 200 a panel and he is claiming cheaper now. I don't know check it out might save you some money.

Sorry but that video is a scam.

 

[Air_Cooled_Nut]

I've found this site to be quite helpful, lots of reading!
http://www.builditsolar.com/index.htm