Registered: 1440223530 Posts: 71
Reply with quote #1
I've been experimenting with passive reflectors in the front yard to the north of my home to reflect winter sunlight both onto the house walls and through the windows. Has anyone else tried this? If so, what were your results?
The initial impetus for this began years back when I was constantly using an outdoor water faucet on the north side of my house to water livestock. The faucet is under an overhanging entry roof and is, of course, also in the shade during winter. It's a 'freeze proof' faucet, however, the hundred feet of hose and so on are not. Yeah, I used to uncouple the hose and drag all of it out where the sun would reach it, plus also holding one end high to drain the hose as much as possible. All in all, using pliers with cold hands in the early a.m. to screw/unscrew hoses is a pain. However, I had a 'senior moment,' otherwise known as a brainstorm. I made up a simple backboard with a partial sheet of scrap plywood, stapled aluminum foil to one side, and mounted a single hinged scrap of 2x4 to act as a leg or prop on the back side. Hey, it works! I'd go out in the early morning after leaving the female end of the hose screwed to the faucet overnight, set up my reflector, and aim sunlight into the faucet area. I was surprised at the amount of solar heat reflected into that under roof space and onto the faucet and attached hose. Usually the ice in the hose would break loose in no more than 20 minutes even on a single digit day and I'd have water flowing into the cattle trough. Just a trickle at first but once water is flowing a stream of ice chunks soon follows and then full pressure water flows. That got me to thinking about reflectors for the entire north face of the house which is about 135 feet east to west and all thick adobe except for nine 3'x6' windows. Now I'm setting up some temporary 4x8 foot plywood sheets covered with foil and positioned to aim at broad areas of the house. Yes, the areas of reflected light change as the sun rises and begins its east/west journey but the reflectors are simplicity personified. I can make as many as I want propped at varying angles horizontally and vertically to continuously cover that side of the house all day. I could also come up with a simple system to track the sun. By the way, I did design an extremely simple plastic water bucket/rope system for solar cooker tracking a few years back and provided it without cost to a solar cooking forum in India. They were most appreciative and have let me know it's now widely used there in lieu of complex and expensive clockwork and electrical/mechanical methods. Anyway, I did recently mount and aim a 4x8' reflector into my kitchen windows. Then I mounted two steel bookcase shelves temporarily at the bottoms of the kitchen windows and inside. HA! What do you know, the shelves warmed up nicely into the upper 70s and released some nice heat into that side of the kitchen. The additional bright light reflecting from the white kitchen ceiling is also welcome. Hmmm. I could also make frames from ripped 2x4's and staple foil sided insulation or even roof flashing to the frames. We shall see. Anyway, comments and suggestions are welcome.
Registered: 1388591029 Posts: 2,685
Reply with quote #2
There was quite a discussion and some experimentation on the subject last fall I think after it was determined that light reflected off the snow improved the output.
As my roof is white I've thought of mounting my smaller collectors there to get some gain but I haven't done it. I'm really not into hauling collectors up ladders... I suppose if one were into landscaping one could do the same with a bed of white rocks. __________________ Solar is like the wind. It may be free, but putting it to work isn't! Willie, Tampa Bay
Registered: 1359070732 Posts: 2,240
Reply with quote #3
some nice work there ! You could search the forum for keywords "mylar reflector" and find some interesting stuff, such as this one by Michael Clarke: http://simplysolar.supporttopics.com/post/snow-versus-mylar-reflector-comparison-7302220?pid=1286240075&highlight=mylar+reflector You might also be interested in doing a web search for "heat island", as this is also another much-ignored topic. (basically, per first-level searches, heat island effect is regarded as negative by virtually all cohorts of planners, but for simply solar, it is sure worth looking into -- I seem to have the beginnings of one around my house !) https://en.wikipedia.org/wiki/Urban_heat_island G_H __________________
(1) "Heat goes from hot to cold, there is no directional bias" (2) It's wrote, "voilà" unless talking musical instruments...
Registered: 1424977490 Posts: 488
Reply with quote #4
Good idea. We just moved from the country where we had all the freedom to do what we like. After the move, we have to be careful about appearances. It can be done but not as easily.
__________________ Bert K. Michigan
Registered: 1378212127 Posts: 554
Reply with quote #5
I use reflectors to increase the output of my hot air solar collectors. I also have one reflecting more light/heat into a window. All use mylar. Aluminum foil works, but is not as reflective and it will degrade outdoors.
Search for "reflector" in these forums or on Builditsolar.com. Kevin H MN
Registered: 1352940256 Posts: 1,024
Reply with quote #6
Originally Posted by
KevinH ... Search for "reflector" in these forums or on Builditsolar.com http://www.builditsolar.com/Experimental/Reflectors/ReflectiveSurfaceVerticalCollector.htm __________________ Both temperature rise and airflow are integral to comparing hot air collectors
Registered: 1378212127 Posts: 554
Reply with quote #7
The main Builditsolar reflector page is here:
http://www.builditsolar.com/Experimental/Reflectors/Main.htm Lots of other links related to reflectors. Kevin H MN