Solar heat for your entire house extremely cheap
 

I WANTED TO PLACE THIS IN BOTH FORUMS IN CASE ANYONE MISSES IT

My Solar Revelation!


I discovered as of recent that using dark color to absorb energy from the sun works very well.. so well I can heat one room to 75 degrees when the sun was just right in the last place I lived, with no other heat sources..

I have made (unedited as of now)videos proving this but the proof is in the pudding,

I just snagged a place with new windows, insulation, and I applied the techniques at my new place

basically the materials consist of dark blue(tinted with blue and black and maybe some purple, not red colors(you can see this when you shine light through a sheet)) bed sheets and black that allow light to pass through basically you use these as curtains on your windows, and when then sun is out on that window pull up the blinds and let the sun hit it, PULL BACK THE END OPPOSITE OF WHERE THE SUN IS HITTING THE SHEET TO ALLOW THE NATURAL CONVECTION OF AIR TO PULL THE HEAT OUT OF THE BLANKET OR SHEET LIKE A RADIATOR,

IN A MATTER OF MINUTES YOU CAN RAISE THE TEMPURATURE OF A WELL INSULATED HOUSE A FEW DEGREES. THIS IS WAY MORE PRACTICAL THAN 30,000$ SOLAR INSTALATIONS, THESE SHEETS ALSO ACT AS CURTAINS OR INSULATION AT NIGHT TO KEEP THE HEAT IN, THIS FORM OF HEAT IS MUCH HEALTHIER AND MORE NATURAL THAN GAS, ITS LESS DRY

I CAN GET THIS PLACE IM IN TO 76 DEGREES USING THIS METHOD, I AM USING A DIGITAL SURFACE THERMOMETER TO DO READINGS.

OTHER PROJECTS USING COLOR INCLUDING SOLAR PANELS MADE OUT OF BLACK PAINTED ALUMINUM OR PLASTIC PIPING SEALED IN A BOX USING A FAN TO BLOW THE HEAT INTO YOUR HOUSE, UNFORTUNATELY ALOT OF THIS STUFF NEEDS PERMITS, PUTTING CURTAINS ON YOUR WINDOWS DOES NOT, AND COSTS A ALOT LESS, I PAYED ABOUT 50$ FOR ALL THE MATERIALS NEEDED FOR THIS FOR 12 WINDOWS.

also 100% flat black paint will add to this, but be careful of semi-gloss paint, it'll add a cooling effect to your house, flat paint is warmer feeling and absorbs more heat energy you can paint ect if you find true flat unltra black paint, but paint manufactures don't have this available, I found a gallon of 15 year old black paint on the curb being given away with other paint AND THE PIGMENTS IN THAT PAINT ARE MUCH DIFFERENT AND RICHER THAN NEW PAINT, DUE TO EPA REGULATIONS AND CHANGES IN PAINT MIXTURES PAINT HAS BEEN MADE TO NOT ABSORB AS MUCH HEAT YOU NEED TO FIND AN EXACT PAINT FOR YOUR APPLICATION IS WHAT I AM SAYING, AND MOST OF THE PAINT OUT THERE IS NOT IT.

For example:
Home depot does not sell any flat paint at all, end of story.
they call it matte/flat, which if you go to a real paint store they will TELL YOU SPECIFICALLY THAT MATTE IS NOT FLAT PAINT REGARDLESS OF WHAT THE GUY AT HOME DEPOT SAYS. I NEED TO RESEARCH THIS MORE, BUT I HEAVE HEARD THAT BLACK EXHAUST PAINT MIGHT WORK..
________

find a room in your house that is cold all the time, try this and then you will understand what im saying also tucking in curtains so theyre snug against the windows helps, air moving against cold glass, also this is the same idea with semi gloss paint, its a colder surface so it can cool your house down more

this will work differently in different climates when its colder outside and the glass on your window is cold so you have to be aware of when to pull up blinds to all the sun to hit the sheets and close the blinds when its done. there is some manual labor but not much and the payoffs are big

It sure seems like leaving the curtains (or shades) open when it's sunny,
and closing them when it's not sunny does about the same thing.

Passive solar heating. I've been doing since 1973..

At this very moment, I have the very bright 8AM sun coming in the windows of my PC room. (Toasty)!
It's saving me heating oil and helping with the S.A.D. at the same time! :)

Cheers,
Rich

white vs black curtains, well white curtains would reflect the sun out of your house and likewise material would conduct less heat in your house, whats important is the surface tempurature while the sun hits it, you could paint your window black and it would be 3 or 4 degrees warmer than if it were white providing they were both flat paint, my point is, if you make a concerted effort to put dark pigmented material where the sunlight hits in your home, then it will emmanate more heat by far, i have this one board i painted with that 15 year old black paint I found and it gets 120 degree F in the sun, i have video documentation of this. if it were white, it would be nowhere near that hot

go buy a digital surface thermometer at autozone for 20$ and do some experimenting.

its about the type of paint we are having a good discussion about this at gassavers .org

they linked me here

do a straight white vs black comparison everywhere you can white pavement vs black white car vs black

this is using the same idea as the solar can heater sort of as far as pigments are concerned black pavement=hot white pavement=not

this is using the same idea as the solar can heater sort of as far as pigments are concerned black pavement=hot

I have tested and proven my method with tempurature measuring tools

When the sun (at a certain power level for a certain amount of time) comes into the window,
and is inside your house..

Some of obviously bounces right back outdoors (unless everything inside is flat black).
People outdoors can see inside, because of that reflected light.

However, looking at the light bouncing outdoors, is not at all like looking at the sun.
The watts per sq meter are very low..

My point is, almost all (90% ?) the light getting inside my windows will stay inside the house.

So, what happens to those photons?

Do they all end up absorbed and turned into heat?

It seems they do not remain in their 'light' state. Otherwise they would
accumulate indoors and it would be like living inside a Laser tube..

My guess is, they are mostly converted into heat..
(Unless you have some PV panels in the room).. :D


So, the question that comes to mind.. If 100 watts of solar power (light)
comes into this room and 10% bounces right back outdoors..

Would the color of the room really make much difference to
remaining the 90 watts of energy left in the room?

Won't it just scatter around and hit surfaces in the room where it will
be absorbed and turned into heat?

Alot of light and heat can get reflected back, that is why having dark colors help, the dark objects absorb more of the heat from the sunlight, my parents have a sun room with a light colored floor, it's a cold floor in the winter, light colored rugs are also cold on that floor, the dark rugs get warm, it has to do with the reflective quality of the color, but while a dark color soaks up the infrared radiation it will also give it off, so while having dark curtains in the day will help heat the room you want light colors at night by the windows to keep that infrared radiation from being transmitted out, if you want to use your solar hot water panels for cooling then you run them at night, the nights sky soaks up that heat and cools the panels in the same way the window without a curtain on it lets the heat out of your house.

"Alot of light and heat can get reflected back"

To be clear, I'm only talking about light that gets inside the house. Not the sun light reflected off the exterior glass.


What I'm thinking about is a normal room with a mix of dark and light objects inside.

Yes, I know that if everything in the room was painted black, it would not have much light lost back out the windows..

But, in a normal room it seems like (once inside) only a small amount of light bounces back outdoors.
My guess is about 10%.. I could be way off. :o

If it were a lot light coming out, looking into a window from the outdoors, would be almost like looking at the sun..
Like if your room was covered with mirrors, much of the light would just bounce back outdoors.



So, my thinking is, if you have 90% of your light bouncing inside the normal room,
isn't it going to get converted into heat? It can't just bounce around all day.. :D


My point is, whatever comes in the window (and stays) is all you get..
It's going to convert into heat..

If it's 90 watts, it can only convert to 307 BTUh.. No matter the colors of the room.

But one can direct the heat within a room by adjusting the color of the floor/rug, because you want a warm, but not scalding, floor. You do not want to heat the ceiling ordinarily.

[QUOTE=Xringer;6085]"Alot of light and heat can get reflected back"

To be clear, I'm only talking about light that gets inside the house. Not the sun light reflected off the exterior glass.


What I'm thinking about is a normal room with a mix of dark and light objects inside.

Yes, I know that if everything in the room was painted black, it would not have much light lost back out the windows..

But, in a normal room it seems like (once inside) only a small amount of light bounces back outdoors.
My guess is about 10%.. I could be way off. :o

If it were a lot light coming out, looking into a window from the outdoors, would be almost like looking at the sun..
Like if your room was covered with mirrors, much of the light would just bounce back outdoors.

So, my thinking is, if you have 90% of your light bouncing inside the normal room,
isn't it going to get converted into heat? It can't just bounce around all day.. :D




10% is way off, sorry to tell ya, if rays reflect off of something and hit something else, unless that particular item is good at absorbing heat and light energy well then is just a bigger dead end than it was before and semi-gloss paint keeps reflecting this energy away,
I would use dark materials in the day and white blinds(plastic at night)


glossy surfaces have their own heat absorption rates and what you're implying depending upon the rates of everything surrounding the one spot where the sun is hitting. surface vs surface is the big thing here and if you collect the heat at the bottom of a room via black it travels to the top and heats everything on its way, if its only reflected to the ceiling, it stays closer the the ceiling, not that it is, heat is not sun, heat does not bounce off of objects like light, you're confusing too many variables to be right about 10%.

true flat ultra black paint gets 120+ F in the sun and white semi gloss stays at about room temp(68)

When I said it was way off, I mean way too high.. I think the exiting light losses might be much less than 10%..

Here's an URL Understanding Energy-Efficient Windows - Fine Homebuilding Article

I skimmed it fast, but didn't see any number associated with light going backwards out the window..

http://www.finehomebuilding.com/CMS/...0029_03_lg.gif

Hey, those look like my Low-E windows!!
Just looking at that picture, it seems intuitive that what Sunlight comes in the window, stays inside..
Expect for the regular cold air leaks and low R-factor window leakage..

well take that 85-90%(maybe) and multiply it by the percentage of heat absorbant materials inside the room 60%= .6

50% heat retention.

a good test is touch the surface of whatever it is, and if it feels cool to the touch vs like wise other material then that does not absorb heat..

I had a whole bunch of metal (steel stuff) in my kitchen this winter and once I removed that it warmed up a little, because the metal absorbs cold and radiates it.

I had pure black carpets, and black window sills and raised the temp of that particular uninsulated room with bad windows(seal and pealed) from 56 degree in the 20 degree morning to 75 by 2pm

I had one window where half was white and half was black in the sun all day, and the temp reading for the white part was 71 degrees while the black portion was 74-75 constantly and thats wood..

you can find other materials that would work way better than this inside too, an aluminum window heater for example painted in black

I was just looking at some inside storm windows..
Larson Manufacturing

They look very easy to install and may even be available in Low-E glass..
I think maybe I'll call Lowes and see if they can order some for me.

With those on the inside, I would have 3 panes of glass and a lot lower heat losses.



Of course, there is always one more step.. :D

Larson Gold Series storm windows are premium, top-of-the-line storm windows. - Larson Manufacturing

Exterior Storm windows! Dang! 4 panes of glass is three layers of trapped air insulation!!

That would really hold in the heat..

plexi glass and seal and peal on the outside of your windows works too..

my curtains tuck in is just something you can do on the cheap that works well..

caulking and tracking down air leaks is big

It sounds like the success to your method is coming from your curtains at night more than anything else. Heavy curtains that prevent a cooling "heat engine" from setting up on the glass surface is critical to retaining heat at night.

I agree with Xringer--unless you are transmitting heat or visible light back out of the window, what energy comes in effectively stays in, regardless of the color of the objects in the room.

This is why you want to increase your absorber/window area during the day with heat absorbing panels of some kind piped into the room during the day, with the same path blocked off during the night.

Incidentally, this out-transmission of energy is pretty much the largest heat loss in solar heating panels. Most of it occurs in the form of radiant heat loss right back out the glass/lens of the panel.

"Incidentally, this out-transmission of energy is pretty much the largest heat loss in solar heating panels.
Most of it occurs in the form of radiant heat loss right back out the glass/lens of the panel."

That's not really a big deal on solar hot-water systems, since the pumps turn off when the sun isn't out.
So, only the panel cools off, and not the hot-water in storage. :)

I remember my old hot-water panels warmed up super quick when the sun hit them in the morning.
I could hear the circulator pumps kick in pretty early in the morning.

~~~
IIRC, there was some kind of scheme to circulate coolant up to the cool
collectors at night, to capture some of that cold and pump it down into
the warmed-up house for cooling during warm summer nights.
Not sure how that would work around here..
(Actually, indoor heat would be pumped up to the roof).

that's exactly what I am doing(tucking it around shades at night) but dark blue works perfect for this, you must be able to see some of the sun come through the other side I think for this to work as it, from what I have read here, I assume this would allow excess solar radiation to stay inside the house, such as with this 2 millimeter thick sheet
this works extremely well better than spending a ton of money

by this, I mean this heats up your house instantly go buy a thermometer and surface temp reader... and $15 worth of sheets to start

exactly why pavement being black is causing global warming

400 thread bed sheets(dark blue) work too for this effect..

I have been testing with the black sheets infront of windows and am getting quite good results. The gains are large. The other morning I was seeing air coming off the top of the drape on the large window at 29.5 celcius and the air is gusting. It will even draw the drape in and stick it to the glass. I believe it is working well about a foot away from the glass so that there is little interaction with the glass with a good gap at the top and bottom. This is producing good heat even when the window is in the shade or there are clouds. Some windows appear to produce more on cloudy days than in shade conditions. At first I thought it would not make any difference but it makes a big difference. We have all white walls inside and the neighbouring houses are all painted white on the outside. This is to keep things cool in the summer. They have a rough finish to disperse the light. In the winter this is working beautifully because there is piles of light in all directions. Anyway with white walls inside a large proportion of the light is coming back out of the room. It comes out just as easy as it can get in. This is why you can see lights on in a house from miles away. With the black drapes most of it is not getting more than a foot in and most of the rest is getting caught on the way out. The temperatures are much higher than I have been able to get in previous years at this time of the year. I am planning to make up drapes for all the windows for a total of 17 square metres of collectors. I was trying to build external collectors but it is much easier and cheaper to use the existing windows and you get a huge panel at little cost. When they have strong light I get 4 or 5 degrees celcius warming on a single pass (up about 6 feet). The air is off towards the ceiling and away after only a few seconds and piles of it. I can feel the house go into a fortex with strong currents and over the days it is heating the neighbours house and going down underneath. On lower light conditions it still increases passing air a degree or two! and the air comes round to be reheated over and over again. The other morning there was a gail coming down the far wall where the heated air was pouring down as the heat was being absorbed by the wall. This would certainly save people billions of dollars in heating costs if it was widely used. A lot of the time the light isn't needed for anything (else:)) e.g. if people are out at work or in the bedrooms that are not being used during the day. If using a room some drapes can be removed for lighting but the insides of the remaining drapes will still take up a lot of that light before it has a chance to leave the room. In locations further north the production would be somewhat lower in December and January but if there is any light it is working and they still require heating in March and April when the days are much longer. They also generally have much better insulation than here and some houses could even over heat if there was too little absorption by the walls.

Cleaning the windows appears to significantly increase heat production and at night the drapes help reduce air moving over the glass and creates a cusion of cooler air there or atleast brings the cooled air down to the floor where it can be warmed by the stored heat. The inside of the room is acting as a huge battery. By making the drapes with plenty of space for air to pass in the bottom and out the top air does not warm as much in one pass but much more of it is is heated and quickly spread more evenly down to the floors. By having a bit of a curve outwards at the top the heated air rising on the indoors side of the drape appears to cause some suction and help draw the air out from the window side of the drape. The drapes may require some weighting (paperclips) to prevent it getting sucked onto the glass when there is full sun. When there is full sun however the glass and metal frame of the windows warms up so the vaccum (drape getting sucked closer to the glass) can work as an advantage as you can get high speeds of air drawing off extra heat from the glass and frame whilst being further away under lower light (cold glass) conditions.

I am planning to get hold of more fabric that is cotton as this should produce safe heat without contaminating the air as some synthetic materials would. The only concern I think is if the dyes give off any toxins when heated but if the material is intended for clothing and making drapes I would hope that is should be safe and with so much air moving over and thru the material it isn't even getting hot to the touch. I generally change all the air atleast once a day in any case. With vapour from an electronic cigerette I am able to really see what is happening e.g. how fast air is moving and which direction.

This would be a great little business to install these for people. I was thinking you know you take the measurments, cut the material and have seams sown on and hang them on hooks or existing curtain rails. Easy money.

You might try different fabrics.
Try wool, it might be too heavy but is super insulative. Or try silk, not sure if there are different kinds of silk, thermasilk long johns are quite warm, light weight. Flannel cotton might be the cheapest warm natural fabric.

What you all are discussing here is known as a selective surface. Flat black paints and fabric dyes are good absorbers (i.e. they absorb visible and uv light) but they re-radiate most of the light they absorb in the near or middle infrared spectrum. They work much like the fluorescent colors, such as hot pink and blaze orange. If you put a uv light up to these colors, they glow brightly because they are absorbing uv light and emitting it at visible wavelengths.

The dyes you are speaking of do the opposite. They simply "bend" the visible light a little down the spectrum into the near infrared. You can't see it, so it tricks your eyes, but the near infrared radiation bounces around the room just about as well as visible light.

In order for a material to be a good selective surface, it should not re-radiate much (if any) of its gathered energy at a wavelength higher than its incident temperature. For this window collector, all the energy collected should be radiated in the far infrared spectrum. The long-wave infrared is the stuff that comes off hot plates and electric skillets and buck stoves. The more energy you can emit at these frequencies, the better your selective surface is.

Here's a good list:

Heliostat Concepts

Two things are keeping me from trying this project. First of all, we have 9 1/2' of exterior roof / overhang on the south side of the building {8' porch roof + 1 1/2' overhang} and a wife who would not accept a sizable amount of flat black into the room.

Keep in mind that it's always easier to increase the home's temperature when other heat sources such as space and radiator heaters remain active... Once you turn everything off and rely only on one source, the true story emerges.

Now I save money the old fashioned way, too.
By dressing appropriately for the climate.

You don't wear warm clothes in my house, you will be uncomfortable.

http://ecorenovator.org/forum/attach...p-img_3476-jpg

Somebody forgot to wipe down their Remote !

This may be hard to believe but there is no remote for that thermostat.

might be for the best , they tend to get lost fast with more than one person in the house and especially with children around.

I will go away now..haha

Heating your home with solar. Something I experimented with a little last winter.

My results: open curtains in the day and closed at night seems to work, but I found a better method. Similar to what "Solar" has said, I put black cloth over the windows. I left a 2-3in gap at the top and bottom. I covered the entire window when the sun stopped shining on it. The effect I noticed was the sun would heat the black fabric and the heat would rise into the room. Using a ceiling fan helped distribute the warmth. On the majority of winter days, I was able to keep my whole house warm (60+ degrees F) when the sun was shining (in other words, I didn't use any other form of heat during most winter days despite temperatures outside being between 20-35 degrees F). I didn't manage to figure out any worthwhile solution to STORING any heat and had to use supplemental heat at night. My home is setup in a rather useful way. Half the windows are on the south facing side and half on the north facing side. In the summer I can block the south windows and leave the north windows bare and it helps keep the inside temps a little cooler. The best effect I've seen this summer is 10 degrees cooler inside than outside without the use of any air conditioning (using ventilation through the north side windows with the help of nearby trees). This winter I may attempt a little more "radical" solar heating setup just to see how well it works. Basically a large exterior box to collect solar heat and pump it into the house. Still not sure a good way to store any collected heat. It helps though that I have low ceilings and a large south facing exposure compared to the square footage of the house (think rectangular).

Now, the "average" BTUs in sunlight on an "average" day is around 300 useful BTUs per hour per square foot. If you halve it, that's still 150 BTUs per hour per square foot. A watt can be turned into 3.412 BTUs. So a square foot of area could realistically see about 44 watts worth of heat on a winter day. The exact amount can vary WILDLY depending on so many factors. Just roughly estimating here and trying to be conservative.

So, let's assume you have a room that is 100 square feet and of "average" insulation with 7ft ceiling. You will "typically" need about 7,600 btus an hour to heat it in a typical cold area of the USA (sorry Canada, this example is not for you). This figure too can vary WILDLY. So you would need about 50 square feet of solar collection to heat that room entirely with solar and be pretty dang sure. Of course this will only be during sunny days when the sun is actually shining on the collector. So, you would need a collection area of roughly seven feet by seven feet. Using a typical window, the collection box could be about 3ft by 16 foot. So in theory for a 100 square foot room with a south facing window, you could heat it entirely with solar by having a roughly 3ft by 16ft solar collector. You could also just install a bunch of windows lol.

Can a home be entirely heated by solar? Of course. Can a typical home be heated entirely by passive solar? Probably not without a lot of work. Can you save money by using solar to help heat your home? Of course. Just realize one typical south facing window in a room will not do all that much if your house is not heated by other means. It's still worth it. For a typical window, you could gain about 2200 BTU/hr of heat that doesn't cost you a penny. Almost like a 650 watt heater running. About 75-80 kWh a month of free heat if you get four hours of good sunlight every day. Of course you will probably get closer to 50. For me, that is $5 a month I could save for one room by spending roughly a few minutes a month opening and closing the window curtain. Multiply that by however many windows you have that can get good solar. Not bad and worth it to me.

The issue with solar is it isn't a steady constant source of heat. If you get a string of cloudy days, you will be using some other form of heat. A rocket stove mass heater may be a better solution for small homes. Not sure about large homes. Of course the best solution would be to build a house to be heated passively by solar, store the heat for the night time, and be passively cooled in the summer. Earthships come to mind (and boy can they be pricey).

If I made errors in my stats/calculations, forgive me. It's late, I'm tired.

As the temperature of the heat source increases the wavelength of the light( and heat ) gets shorter. As the sun is so hot the light easily passes through the glass. When it heats the black material up that starts to radiate but the wavelength is much higher than from the sun and it doesn't pass through the glass so well. A very good article is at https://phys.libretexts.org/Bookshel...body_Radiation.