How many others have a passive solar house?

[MrWinkey]

Evening!

I was just wondering how many other people are living in passive solar houses?

http://www.nesea.org/buildings/passive.html

The design I'm living in now is the one on the right w/ the large overhangs.

My plan in another 5-10 years is to build the masonry heater the house was designed for and has the foundation.

Thanks!

 

[Rick]

The original part of my home was built with passive solar in mind, as well as having the correct orientation and pitch to the roof for solar panels. I spoke to the original owner of my home, and he explained it all to me. He also told me that around Christmas the sun will hit the back wall of my bedroom, and it does. That part of my house is very easy to heat and keep warm, not so easy to keep cool.

 

[Mike Wilson]

I have a full on passive system in my home. In addition to other south facing windows in side rooms, we have 12 large Andersen windows in a south facing central atrium that is 34' high, with stone tile floors and an indoor soil garden (complete with 25' tall tree!) The windows are 6' by 3', are mounted 4 across and 3 high, and so long as the wind is not blowing, on a 40 degree day, the house is 74 inside. A ceiling fan moves the heat around pretty well. The garden area acts as a large humidifier. The dirt in the garden is actually the soil beneath the house, which is to say, the foundation surrounds the garden in a 12' by 12' square. There is a drip and mist irrigation system that keeps the soil moist, and as the sun hits the soil, the water evaporates into the air... pretty neat way of doing it. I also have solar hot water. No solar electric though, its just not cost effective, the ROI sucks right now.

-- Mike

 

[JohnnyBravo]

im in the process of building a house for my parents. lots of solar gain in the design. in fact i listed it as the main heat source because if the hydronic was the main source the design would have had to be engineered. now its a secondary along with the quad 7100.

 

[ozarkjeep]

Hey Mike,

that sounds like a really nice looking AND workable system, do you have photos? other specs? a build thread or website?

Id love to see it and read about it.

I have a full on passive system in my home. In addition to other south facing windows in side rooms, we have 12 large Andersen windows in a south facing central atrium that is 34' high, with stone tile floors and an indoor soil garden (complete with 25' tall tree!) The windows are 6' by 3', are mounted 4 across and 3 high, and so long as the wind is not blowing, on a 40 degree day, the house is 74 inside. A ceiling fan moves the heat around pretty well. The garden area acts as a large humidifier. The dirt in the garden is actually the soil beneath the house, which is to say, the foundation surrounds the garden in a 12' by 12' square. There is a drip and mist irrigation system that keeps the soil moist, and as the sun hits the soil, the water evaporates into the air... pretty neat way of doing it. I also have solar hot water. No solar electric though, its just not cost effective, the ROI sucks right now.

-- Mike

 

[begreen]

I have a full on passive system in my home. In addition to other south facing windows in side rooms, we have 12 large Andersen windows in a south facing central atrium that is 34' high, with stone tile floors and an indoor soil garden (complete with 25' tall tree!) The windows are 6' by 3', are mounted 4 across and 3 high, and so long as the wind is not blowing, on a 40 degree day, the house is 74 inside. A ceiling fan moves the heat around pretty well. The garden area acts as a large humidifier. The dirt in the garden is actually the soil beneath the house, which is to say, the foundation surrounds the garden in a 12' by 12' square. There is a drip and mist irrigation system that keeps the soil moist, and as the sun hits the soil, the water evaporates into the air... pretty neat way of doing it. I also have solar hot water. No solar electric though, its just not cost effective, the ROI sucks right now.

-- Mike

Sounds like a great layout, but that just blew "cheap" out the window. Frugal maybe, it's a good investment in quality for the future. But no way is this cheap.

 

[Mike Wilson]

Green,
I suppose not, but its not that expensive either. It was the original design of the house, which is the best time to address these issues. In essence, all it is is a big room with a lot of windows facing south, and a tile floor. Not a big deal, you could do it in a kitchen, or even a hallway in another house. The garden part was the architect's idea, of course. We like it because of the greenery, but again, I can't see a very major expense if you do it new construction, all it is is four poured concrete footings, one of which is the exterior footing for the house anyway. The irrigation system is basically just plastic tubing and spray or drip heads on a timer, the whole thing probably costs a few hundred, tops. As for the solar hot water, its glycol based, and amounts to 3 panels on the roof with some tubing and a backup water heater in the basement. As for plans to the house, it was custom, so there aren't any set plans. Its not some great solar house design, just that some solar design was considered in the layout. It's not what I would call a pure "solar house" design. That would, in my opinion, need some element of solar electric, a much larger solar hot water storage system, and perhaps a solar hot water heating system. Also, what you said about it being an investment in the future is true. I've been in this house 10 years, and don't plan to move, so I am getting a return on this investment.

I am still looking for ways to maximize solar in this place. It's become an academic game of sorts... collecting it, keeping it, etc. I had them install triple insulated cellular shades on most all the windows here, and I raise and lower them as the sun and weather dictate. Once the sun starts heading down, down come the shades to store the heat better. I actually modified my burning in the beginning and end of the season somewhat. Instead of burning full on for 24 hours, now I load up at around 3- 4PM, then again at 11:30, and then, instead of a full load at 6 when I wake, I just put enough in to get some secondary, take the chill off, and give me enough coals at 4PM, when I start the burns again. It extends the life of my wood pile. Now, in January and February, of course, I have to burn 24/7 with 3 full loads, especially when its overcast and windy.

-- Mike

 

[Nofossil]

Ours is passive solar. South side is full three stories, lots of low-e glass (and an insulated garage door for access to my basement shop). North side is 1 1/2 stories with only two pitiful windows. Garage also covers part of the north side.

Solarium in center of south side is full three stories - screened, not glazed, but allows winter sun all the way in to north walls of interior.

Next project is automatic solar powered mylar blinds. Glass is nice during the day, but closing 22 big blinds every night and opening them every morning is not realistic in our house at least.

 

[MrWinkey]

Let me know how the Mylar blinds project works out. That sounds like something I need.

My project in 5 years is to build the Russian/Masonry fireplace and move the pellet stove. The house was designed for one but it was never installed due to cost. That way I can have the best of both worlds and maybe a sweet pizza oven!

Ok maybe the turkey also......

 

[Rhone]

nofossil why lots of low-e on south side? Low-e glass prevents the suns free energy. Unfortunately it not only stops radiant energy from leaving it prevents it from entering too. The windows with the best solar gain are simple double-pane, not low-e nor argon/krypton filled. But at night you have to cover them as double-pane windows will lose a lot of heat.

I have 2 windows on the south side of my house, one is low-e argon the other simple double pane. When I was caulking around the windows during my lunch break one fall day doing the low-e window didn't notice I was in the sun at all. Went to do likewise with my other south window that's just double-pane and in short order was sweating to death.

 

[babalu87]

We have a cape that faces due south on the "window side"
Two of those windows are sliders and it is pretty rare to have the stove going once the sun starts hitting the house. I think only once and it was biting cold and VERY windy that day.
Pretty much night time fires for us unless its cold AND cloudy.

The downside, it gets hotter in July and August but thats what they make shades for

 

[Nofossil]

nofossil why lots of low-e on south side? Low-e glass prevents the suns free energy. Unfortunately it not only stops radiant energy from leaving it prevents it from entering too. The windows with the best solar gain are simple double-pane, not low-e nor argon/krypton filled. But at night you have to cover them as double-pane windows will lose a lot of heat.

I have 2 windows on the south side of my house, one is low-e argon the other simple double pane. When I was caulking around the windows during my lunch break one fall day doing the low-e window didn't notice I was in the sun at all. Went to do likewise with my other south window that's just double-pane and in short order was sweating to death.

This is always a balancing act. In our case, there's only an average of maybe six hours of usable solar gain per day during the winter (many days, it's zero). When the sun is shining, I get more than enough solar gain even with the low-e glass. During the other 18 hours per day, it's more important to reduce loss.

Right now it's 38 outside and 73 inside. My thermostat is set for 70, and it hasn't called for heat in over four hours. I need to avoid losing heat tonight more than I need additional heat right now.

A real solar design would have some thermal mass for the sun to work on right now. We don't have that.

 

[MrWinkey]

My plan is to put dark color tiles in front of the sliding glass doors. I usually hang blinds in front of the sliding glass doors in the summer.

Sliding glass doors in front of my house are 3 pane glass and yes I have massive drapes in front to help w/ heat loss.

Maybe some slate or granite would look nice......

 

[ilmbg]

I see there were not many responses to who has passive solar- I wonder if there are more full/active solar owners? Also- none in my area-Northern Wyoming. I have passive, with 6" solid concrete walls, north,west and east on the first 11/2 floor, then frame on the upper 1/2 of the 2nd floor. South almost solid window on 1st floor- upper is cathedral ceiling. I used to have only a wood stove, have gone to pellet. Like wood better. I wish I were off the grid, but am not able to do alot of maintinance due to an injury. I will be building in Texas soon, and would like to go as passive as feasible there. Cement statined floor, large windows, sprayed insulation, solar light tubes, large overhangs, using dishwasher drawers as I do now, front load washer, rain catch water for plants, orientation to sun, etc. I will try to find passive info for that area. I wish it would become more popular by making building prices better- some kind of incentives-whatever. I hope passive solar is popular, but have no idea if it is. Anyone know about anybody?? Austin area. Thanks

 

[mrtrout]

Hello,

I live in a very simple, well engineered passive solar house which performs beautifully. Approx 80% of the total number of BTU's needed to maintain 70 degrees is provided by solar energy. The main part of the system is comprised of a Trombe wall and quarry tile floor. The Trombe wall is the main heat sink and is comprised of 200,000 lbs of solid concrete. To help prevent heat loss through the windows at night, a self inflating solar curtain automatically closes at night or when there is a prolonged coverage of the sun. I can't say enough about the performance of this house. I live at 7500 ft elevation in Colorado where the winters can be fairly brutal.

 

[msjones]

mrtrout,
How did you incorporate your trombe wall into your design? Was it interior or exterior?

And would you be kind enough to explain your solar curtain? Did you design it your self?

Thanks,
Mark

 

[mrtrout]

Hi Mark,

There are two Trombe walls, one interior and one exterior. The interior one utilizes solar energy from the "main" windows the other exterior one utilizes solar energy from glazing immediately in front of it. The exterior one is painted black. The solar curtain is not my design and is covered by a patent held by a major blind manufacturer. It is truly amazing in its function in that it self inflates. I don't completely understand how it works other than than when it is un-rolled, the air in it heats up and expands creating an air space that varies from around 5" to 18" depending on the temperature differential between the interior air and the air temp next to the glazing. The larger the temp differential, the "thicker" it gets. On very cold nights (below zero) it is not uncommon to have 1/4 inch or more of ice on the interior side of the glazing. This curtain is controlled by a temperature sensor which compares the houses interior temp versus a sensors temp outside. Hope this helps

 

[ilmbg]

mrtrout- will you give me an idea of how much a 200,000# of concrete is? About how big is this mass? I assume that it is all above ground? Trying to get a picture in my mind. Thanks. The poster who mentioned that window banks for accumulating heat in cold weather also is gaining heat in the winter is correct, at least in my house. I have to have shades to block the heat in the summer.

 

[msjones]

mrtrout
Your interior trombe, is that some sort of concrete planter, or just solid concrete. How is it incorporated into your layout? Does your exterior trombe wall block you view or is it designed not to. The reason I am asking is I am starting to design my own passive solar home and am looking for ideas. I am not sure if I want to just use south facing windows reflecting on a thermal mass (concrete floor) or some sort of green house with a trombe or thermal mass wall. Right now I am open to suggestions.

 

[mrtrout]

Hi Mark,

The interior wall divides part of the lower and upper level lengthwise and is about 20 ft wide and 20 feet tall. The "exterior" wall is about 12ft wide by 20 feet tall and yes it does block my view as it is solid. For the viewer asking abot how much concrete 200,000 lbs is, a cubic yard of concrete weighs about 4,000 lbs so... the volume would be about 50 cubic yards or if you were to pour a slab 6 inches thick, it would be enough to pour about 2,500 square feet (50ft by 50ft). Hope this helps

 

[caretaker]

I do and have alot of sun exposure, I think when my roof need to be replaced in a couple of years, going with solar panels

 

[amkazen]

HI, Our home has both passive and active solar aspects to it. We are approx. 15 degrees off due south (towards southeast). The south wall of our house is 1/2 Caradco sliding glass doors and the other half has 2 large Caradco awning windows. The floor inside is ceramic tile on a 3" base of gypcrete. Our power is provided by 16 Kyocera KC-130 photovoltaic modules with the power being stored in 24 Interstate L-16 6-volt batteries, with the charge being controlled by an Outback MX-60 charge controller, and the power being inverted from the stored DC power to AC by 2 Trace SW5548 Inverters. We also have a Kohler 11kw propane powered generator for back-up power. We did not go with solar hot water due to the lack of experienced solar hot water folks in this area when we started building 6 1/2 years ago, and also due to my impatience in getting the building started. Was it cost effective to go full solar in this area? No, as it is a 30-year break even point at the least, and when you count on replacing 24 batteries every 5 - 8 years at $200 per battery the payback is even longer. The new rebates, etc. will help but in this area the payback is still not there as the usual residential electric bill in town is probably approx. $100. Now, in CA, where the average residential electric bill is probably $200, and with CA's far greater tax credits, rebates, etc., it is a no-brainer to go solar. Why did we go solar if the payback is not there? After 5 years of looking for vacant land to build on and move out of the city, we found this little undiscovered subdivision north of Albuquerque and my wife fell in love with it. The problem with it was the subdivision was involved in the middle of a 10 year + lawsuit with a local Indian Pueblo/tribe, along with the fact 99% of people believed the land belonged to either the US Forest Service or the Indians. And, because of the Indians, utilities had never been brought into the subdivison. Now, this area is finally starting to be discovered and houses are springing up like crazy, all off-grid. Utilities will never be brought in because the Indians have moved on from a large Bingo tent to a full-blown mega casino-resort and they have millions of dollars ready to fight the utilities, plus the lawsuit settlement specifically did not mention our subdivision y names but did mention the other two subdivisions where the settlement discussed the issue of utilities. So, that is why we are off-grid: my wife fell in love with the area, and the Indians will not allow utilities here.