Solar heater project

[bomber991]

Alright, so I got bored the other day and googled "Homeade Heater". Really didn't find much except for something about solar heaters. Anyways, what I ended up building went pretty far away from the designs I saw.



That's how I planned for it to work. Tape it up to the window and then there is a pocket of air created between the heater box and the window. The black backing in the box absorbs the heat from the sun and warms up the air in the box. The hot air rises out of the top, new air gets sucked in the bottom.

All the fancy designs specify using wood instead of cardboard, and then placing plexiglass over the created box. I figure taping the box to the window would have the same effect. Also they used some sort of insulation foam and paint instead of just a black trashbag.

I guess the idea is that you want to create a similar effect as a car getting hot by sitting in the sun.

Anyways, all I used was cardboard and a trashbag to get the inside of it black. Tried it on a window today and it was producing some warmer air, but not nearly as much as I would have liked. So I taped up some of the holes at the top so that maybe the air might heat up more before it gets out. I'll find out tomorrow. I was also thinking of warping a blanket around it because I'm sure cardboard is not the best insulator.

Here's some pictures, don't have a picture of it installed. Installed being the fancy word that means it's just tapped to the window

[Daox]

Unfortunately, I can't see your pictures due to my workplace's blocking software. But, how does this device differ from just using black curtains? I can see yours offering more airflow, but I would think both would capture the same amount of heat.

[BailOut]

I would like to know how much of a temperature delta this creates in the space you plan to use it in. Please keep us updated.

[brick]

In this application I think you would do just as well to leave the curtains open and let the sun pour in to heat the room and give you natural light. (Depends on how efficient your window is, I guess.) But in principle this design can be very useful. Purpose-built passive solar homes use this concept to utilize additional exterior wall space to generate heat. The advantage of that vs. more windows is that you can close it off during the warmer months and at night without much fuss. Better yet, you can reconfigure it to ventillate and cool the home by drawing air from the bottom which rises as it's heated and is dumped to the exterior at the top of the panel. That draft can move a lot of air!

[shifty35]

www.enertia.com

Entire house built on this principle... I'd love to build one...

[bomber991]

Originally Posted by Daox

Unfortunately, I can't see your pictures due to my workplace's blocking software. But, how does this device differ from just using black curtains? I can see yours offering more airflow, but I would think both would capture the same amount of heat.

You're right that this is similar to using black curtains. I guess the curtains would be like leaving a car in the sun with the windows cracked whereas the box I built is more like having the windows up all the way. But even though more heat would escape with the curtains it still goes into the room.

Originally Posted by BailOut

I would like to know how much of a temperature delta this creates in the space you plan to use it in. Please keep us updated.

Well with all of the fancy plans using wood, plexiglas, and some insulation material they report a change of 5 to 15 degrees Farenheit. I'd imagine with my bad craftsmanship and sub-par materials, the change would be less than 5.

Originally Posted by brick

In this application I think you would do just as well to leave the curtains open and let the sun pour in to heat the room and give you natural light. (Depends on how efficient your window is, I guess.) But in principle this design can be very useful. Purpose-built passive solar homes use this concept to utilize additional exterior wall space to generate heat. The advantage of that vs. more windows is that you can close it off during the warmer months and at night without much fuss. Better yet, you can reconfigure it to ventillate and cool the home by drawing air from the bottom which rises as it's heated and is dumped to the exterior at the top of the panel. That draft can move a lot of air!

My plan is to put the heater box thingy at the bottom half of the window, and still use the top half for lighting. When you go outside and wear a black shirt, you'll notice it gets a lot hotter than a white shirt, so that's the concept of the solar heater I think. You want all the light to hit dark material since it warms up the most.

Originally Posted by shifty35

www.enertia.com

Entire house built on this principle... I'd love to build one...

Neat stuff.

Anyways I can't really do much with the solar heater this week because it's supposed to be cloudy and rainy all week. But for some design changes, I think I need to make it a little smaller, because tape doesn't stick very well to the window frame, but it sticks to glass just fine.