Question:
I just read a book written by the Hawkweed Group, a solar architectural firm from Wisconsin. They make a claim that a passive solar house can be built just as cheaply (or even cheaper) than a conventional house, and that over 90% of the heating requirements of the house will be provided by the sun. They state that contractors bid’s for at least some of the buildings that they designed were competitive with conventional construction. They do not, however, provide any data to support the 90%+ claim. I believe that this book was published around 10 years ago, and there are all sorts of predictions about solar homes becoming popular, etc., etc. This obviously hasn’t happened. I live in an area of the country where solar power would appear to make a great deal of sense. However, all I see is the occasional active solar panel, probably only used for hot water, and probably installed back when there were generous tax incentives for solar retrofits. So, what’s the story? (1) – These guys are liars, and are just trying to drum up business by publishing this book. (2) – Builders won’t risk building solar homes because there’s a good chance that they won’t sell. (3) – People don’t want solar homes because they are ugly. (4) – Other. Please specify. I left out the argument that most houses are built on small lots today and will eventually be shaded by tall trees. Where I live, there are no trees in new subdivisions and it will take quite a few years before shading is a problem. If a passive solar house really costs the same to build, and people could save $30-$100/month on heating bills, why aren’t they insisting on them? I suspect that a passive solar home really does cost more, and that item (3) is a BIG issue (hence item (2) follows as a corollary). — Duane Jacobson
Response:
I have followed the passive solar home movement and literature, designs, etc since the 1970’s. I have to agree that passive solar is not significantly more expensive than a more ==typical== home construction. I would have to say: Item 3—People won’t buy passive solar homes because they are ugly. However, I would substitute the word ==non conformist== rather than ugly. There is always that perennial fear in terms of real estate value: if the owners want to sell some day, will the home be too odd in appearance to keep up with r.e. value, and will the neighbors worry about having such a house on their block, etc. etc. It is a disappointment in my view, to say the least. The 70’s brought great interest and a variety of excellent designs were built, mostly spurred by the so called gasoline/oil shortages, crisis, etc. When that problem went away so did interest in passive solar. — Capt. Kirk: let’s head for that planet, third from the sun, it looks promising…. |-)
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>Item 3—People won’t buy passive solar homes because they are >ugly. >However, I would substitute the word ==non conformist== rather >than ugly. There is always that perennial fear in terms of >real estate value: if the owners want to sell some day, will >the home be too odd in appearance to keep up with r.e. value, >and will the neighbors worry about having such a house on >their block, etc. etc.
Also, I would have to add that if the existing solar technology in that house happens to be phased out, you’ve got a several hundred thousand dollar "experiment" on your hands. People buy houses for security, and don’t want to have to rebuild it 10-15 years down the line. Tino — Pay off the national debt — Tax the Church
Response:
> I just read a book written by the Hawkweed Group, a solar architectural > firm from Wisconsin. They make a claim that a passive solar house > can be built just as cheaply (or even cheaper) than a conventional house, > and that over 90% of the heating requirements of the house will be provided > by the sun.
I suspect the trick here is the 90% figure. I bet what they actually show is that the auxiliary heating requirements can be reduced 90% relative to a (then) conventional house. This isn’t all that hard to do — it’s called "superinsulation". Basically, it means fewer and better windows, thicker insulation, and careful attention to achieving air tightness. If the insulation is good enough, the house does not need a central heating system (heat from appliances and bodies does the trick); this can offset much or all of the cost of the extra insulation. Calling this "passive solar" is really a lie, though, since the technique works almost as well even in total darkness. It’s just conservation. Paul F. Dietz
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- Hide quoted text — Show quoted text -> I just read a book written by the Hawkweed Group, a solar architectural > firm from Wisconsin. They make a claim that a passive solar house > can be built just as cheaply (or even cheaper) than a conventional house, > and that over 90% of the heating requirements of the house will be provided > by the sun. >I suspect the trick here is the 90% figure. I bet what they actually >show is that the auxiliary heating requirements can be reduced 90% >relative to a (then) conventional house. >This isn’t all that hard to do — it’s called "superinsulation". >Basically, it means fewer and better windows, thicker insulation, and >careful attention to achieving air tightness. If the insulation is >good enough, the house does not need a central heating system (heat >from appliances and bodies does the trick); this can offset much or >all of the cost of the extra insulation. >Calling this "passive solar" is really a lie, though, since the >technique works almost as well even in total darkness. It’s just >conservation. > Paul F. Dietz
I live in what is called a "passive solar house" that looks like any other ranch style house. It is very well insulated and has low energy bills for both heating and cooling. On a clear day during the winter the energy consumption is low relative to a cloudy day with the same outside temperature. I doubt that the savings due to passive solar amount to 25%. John Neff
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- Hide quoted text — Show quoted text ->Item 3—People won’t buy passive solar homes because they are >ugly. >However, I would substitute the word ==non conformist== rather >than ugly. There is always that perennial fear in terms of >real estate value: if the owners want to sell some day, will >the home be too odd in appearance to keep up with r.e. value, >and will the neighbors worry about having such a house on >their block, etc. etc. >Also, I would have to add that if the existing solar technology in that >house happens to be phased out, you’ve got a several hundred thousand >dollar "experiment" on your hands. People buy houses for security, and >don’t want to have to rebuild it 10-15 years down the line. >Tino >–
Tino, Maybe you could explain how passive solar technology is "phased out" making your home less valuable? The sun comes up, shines in, warms the storage medium, thus warming the home. Simple. The cliff homes at Mesa Verde still absorb heat the way they did when built X thousand years ago. If you’re talking style, homes need to be remodeled every 40 years, passive solar or not. If you’re talking about storage medium, what is the life expectancy of eutectic salts, or other phase change storage media? Could technology create a more efficient storage medium to replace your obsolete 10-15 year old medium? I expect so. When the book was written in 1982, natural gas prices were expected to triple by 1986 when the tax credits for active solar were phased out. As it turned out gas prices were less than they were in 1982 due to the natural gas glut. The active solar industry shrank dramatically, and home buyers didn`t flock to the passive homes because they didn’t need to worry about the costs of heating traditional home styles. With todays emphasis on light, airy spaces, passive solar designs should be right at home.(PUN) Dan Scott Solbourne Computer, Inc. Disclaimer: I’m not in a position to know Solbournes opinions…yet.
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>Maybe you could explain how passive solar technology is "phased out" >making your home less valuable?
Well, as a lot of people who invested in passive solar water heaters in the ’70s discovered, when the equipment fails, and the company that made it has gone out of business, and no local plumber wants to work with it, it’s pretty useless. Disclaimer: Hey, I understand VAXen and VMS. That’s what I get paid for. My understanding of astronomy is purely at the amateur level (or below). So unless what I’m saying is directly related to VAX/VMS, don’t hold me or my organization responsible for it. If it IS related to VAX/VMS, you can try to hold me responsible for it, but my organization had nothing to do with it.
Response:
:I just read a book written by the Hawkweed Group, a solar architectural :firm from Wisconsin. They make a claim that a passive solar house :can be built just as cheaply (or even cheaper) than a conventional house, :and that over 90% of the heating requirements of the house will be provided :by the sun. Hm, a couple of years ago This Old House went back to a firm that made solar powered homes in the 1970’s during the energy crisis. Today the firm just axes the solar power part. It turns out that most of the energy savings came from tons of insulation put into the home. Judging by efforts to insulate my parents old home, I agree that insulation goes a long way, especially with the older houses. I would say that these houses are simply passive houses. — Kenneth Ng Apple and AT&T lawsuits: Just say NO!
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>>Also, I would have to add that if the existing solar technology in that >house happens to be phased out, you’ve got a several hundred thousand >dollar "experiment" on your hands. People buy houses for security, and >don’t want to have to rebuild it 10-15 years down the line. >Maybe you could explain how passive solar technology is "phased out" >making your home less valuable?
I’ll stick to my gas bill (albeit a bit high) than have a roof full of panels fail with no one around to fix them or replace them. Tino — "Here are the young men, the weight on their shoulders…" – J.D. Purdue University School of Nuclear Engineering
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|> |> I just read a book written by the Hawkweed Group, a solar architectural |> firm from Wisconsin. They make a claim that a passive solar house |> can be built just as cheaply (or even cheaper) than a conventional house, |> and that over 90% of the heating requirements of the house will be provided |> by the sun. |> So, what’s the story? [of the lack of solar homes] |> (2) – Builders won’t risk building solar homes because there’s a good |> chance that they won’t sell. |> Builders in general are extremely conservative and focus on making the first cost as low as possible on homes that historically have a good record of sales. |> (3) – People don’t want solar homes because they are ugly. Solar homes can be ugly, but they don’t have to be. |> |> (4) – Other. Please specify. A big problems is the definition of "passive solar house". Any house that is not in a cave has some "passive solar" component. If the definition is the %90 stated above, that may be your answer. Depending on the location the percentage reduction in heating and or cooling which can be achieved "economically" varies considerably. The builders focus on "first cost" is really the problem. That’s why Hurricane Andrew caused so many problems. Unfortunately the consumer (the home buyer) of mass market homes has little choice given the banking system and the builder’s perception of their tastes. It seems that the only way things like this change is through the specification of building codes. This is unfortunate as I would much rather see the market being driven by consumer sophistication and demand. If energy costs were significantly higher this demand for more energy efficient homes might materialize. The "bigger is better" philosophy of americana may be the root of the problem. It is hard to see the quality of an energy efficient home. Those that do see this and perceive the long term economics often demand more efficient, better designed homes. Unfortunately there are few mass market homes that meet this criteria. Most are designed for the most square feet for the buck. Until this philosophy changes we will probably be stuck with the home designs we have. Kevin Knappmiller Solar Lab Colorado State University Fort Collins, CO 80523 (303)491-8215 |> |> I left out the argument that most houses are built on small lots today |> and will eventually be shaded by tall trees. Where I live, there are |> no trees in new subdivisions and it will take quite a few years before |> shading is a problem. If a passive solar house really costs the same |> to build, and people could save $30-$100/month on heating bills, why |> aren’t they insisting on them? |> |> I suspect that a passive solar home really does cost more, and that |> item (3) is a BIG issue (hence item (2) follows as a corollary). |> — |> Duane Jacobson
Response:
The answer to the fear of having an energy system that noone will be willing to service for you is, of course, to acquire or build a system which you are capable of understanding and maintaining yourself. This is referred to as "appropriate technology" in some circles, though it does smack of condescension when somebody tries to decide what sort of technology is appropriate for somebody else. It’s not like solenoid valves or copper pipe are likely to disappear from the face of the earth. However, neither are laziness, greed or peoples’ desire to treat things as appliances even when they are actually dependencies. A simple passive design is usually pretty hard to break or wear out. A robust active design -could- be made reliable, but unfortunately the solar energy field is no more immune to fast-buck antics and corner-cutting than any other industry. — #Irresponsible rantings of the author alone. Any resemblance to persons # #living or dead then yer bummin. May cause drowsiness. Alcohol may inten-# #sify this effect. Pay no attention to the man behind the curtain. Billy!#
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> The answer to the fear of having an energy system that noone will be >willing to service for you is, of course, to acquire or build a system >which you are capable of understanding and maintaining yourself. This >is referred to as "appropriate technology" in some circles, though it >does smack of condescension when somebody tries to decide what sort of >technology is appropriate for somebody else. > It’s not like solenoid valves or copper pipe are likely to disappear >from the face of the earth. However, neither are laziness, greed or peoples’ >desire to treat things as appliances even when they are actually dependencies.
Right. If you are talking about a mass-market technology rather than an experimenter’s dream, it has to maintainable by the local plumber, electrician, etc., or else the company must provide an affordable aftermarket repair service. Considering the number of people I know who don’t even change the oil in their own cars, telling them to repair their own home energy system is a joke. There are large numbers of people today who are not technically literate and don’t care to become so. — | N5WVR | | "If I owned Texas and I owned Hell, I’d rent out Texas and live | | in Hell." -General Sheridan |
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>Also, I would have to add that if the existing solar technology in that >house happens to be phased out, you’ve got a several hundred thousand >dollar "experiment" on your hands. People buy houses for security, and >don’t want to have to rebuild it 10-15 years down the line. >Tino
From my limited readings on the subject, it appears that most passive solar solutions are fairly straighforward ones: direct gain, Trombe walls, sunspaces. These systems have few, if any, moving parts, and should easily last 50 years before needing major repairs. They are built out of ordinary construction materials like glass and concrete, which won’t be "phased out" anytime soon. The problem seems to be getting stuck with an expensive *architectural* experiment on your hands. The books I’ve read make it sound like people will be knocking down your doors in order to buy your solar house. I think not. Let’s face it, a Trombe wall is not going to "blend in" anywhere. A house incorporating sunspaces and direct gain approaches shows the most promise, in my opinion, of being accepted as a "normal" house. But I’m certainly no architect. Any comments? references? I think the challenge is to be able to tell people that your furnace only turned on twice last year, and have them respond with "Oh, the solar arrays must be out back."
Response:
> Item 3—People won’t buy passive solar homes because they are
ugly. Many ugly people have purchased passive solar homes, I did! 
More seriously, I purchased a passive solar, earth bermed house in a small Colorado mountain town (elev. 8500′) 2 years ago. Basic description is "looks average for a mountain resort chalet except is has a lot of windows on the south side". It’s an all-electric house w/ baseboard resistance heat as backup to a wood-burning stove. Avg electricity bill is $28/month. Avg wood bill is $180/year (2 cords). The very high mass of the house (3 sides 8" thich concrete, bermed, 4" concrete/tile floor) provides the thermal lag needed to keep the house comfortably warm when either a) the sun has been out all day or b) the stove was fired on cloudy days (very few in CO). The house is by no means 90% solar heated. Having spent 15 years researching and designing solar homes as a "hobby", I can say that a 90% passive solar is achieveable but at the expense of conventional construction techniques. Unconventional design and construction (Note: looks conventional) are costly affairs (unless you’re an AIA w/ contracting experience). BTW, I received a call from an insurance company offering a comparison quote for homeowner’s insurance. Was asked the usual questions. When it came to "what is your primary heat source?" I replied that I thought it was solar. I then explained that I had electric, wood and solar as potential heat sources. The conversation abruptly ended with the ins. rep saying "We won’t insure anything that’s solar". The rep didn’t ask whether it was passive, active, central, etc. I’m about to send off a nasty-gram to my mortage holder, who referred the insurance company, for a) an unsolicited referral and b) referring a *very* unenlightened insurance company. C’mon Bill, reinstate the alternative energy and conservation tax breaks!! Alan McCartney (StorageTek, Louisville, CO)
Response:
- Hide quoted text — Show quoted text – >So, what’s the story? >(1) – These guys are liars, and are just trying to drum up business by > publishing this book. >(2) – Builders won’t risk building solar homes because there’s a good > chance that they won’t sell. >(3) – People don’t want solar homes because they are ugly. >(4) – Other. Please specify. >I suspect that a passive solar home really does cost more, and that >item (3) is a BIG issue (hence item (2) follows as a corollary). >–
Well, one has to add in the fact that local building codes often forbid the use of certain styles of construction that would allow very cheap passive solar systems. Remember that many of the good solar-heated designs take a holistic perspective and would require a fundamental change in the design of a house — like using an earth berm on one side of the house. I don’t think that passive solar design would necessarily add that much to the cost of a house, but I seem to recall that the main cost in building a house is labor. My father built a 40×20 house himself (not solar) for about $10,000 in materials in 1973. We’ve had quite a bit of inflation since then, so if we add 3 for a fudge factor, we get a material costs of $30,000 for a "typical" non-solar home. Since homes tend to sell for much more than that, we really have to look at the labor cost involved. So I would say that the answer is mostly between 2,3 and 4 (building codes). Probably a little bit of 1, but I wouldn’t say that the people are liars, just a little bit over-enthusiastic, and they might fudge a little here and there. —
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> Well, one has to add in the fact that local building codes often >forbid the use of certain styles of construction that would allow very cheap >passive solar systems.
I did talk to a (Ft Collins) city official about building codes. It seems the major requirement the city has is that it has to meet certain energy (insulation) requirements. This results in fairly restrictive limitations on window sizes. They don’t take into account that, in this part of the country, a double-glazed window with a southern exposure will admit more energy than it loses. I guess this makes sense because most people leave their shades closed during the day so their furniture and carpet aren’t faded by the sun. However, I suspect that community covenants and restrictions offer more insurmountable roadblocks to passive solar construction than building codes. Homeowners’ associations seem to be much more concerned about home style than (my) city government does.
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|> I’ll stick to my gas bill (albeit a bit high) than have a roof full of |> panels fail with no one around to fix them or replace them. |> |> Tino It seems like many people are confused about the definition of "Passive" Solar as opposed to "Active" Solar. A roof full of panels and their associated systems is "Active" Solar. A house with windows, insulation, and mass is "Passive" Solar. As you will probably notice this covers just about any house, hence the vagueness of the definition. Realistically one more accurately talks about "incorporating passive solar concepts into the design of a building". This way one doesn’t have to say one has a home heated by solar energy and be refused insurance as Alan McCartney was. Kevin Knappmiller Solar Lab Colorado State University Fort Collins, CO 80523 (303)491-8215
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>I’ll stick to my gas bill (albeit a bit high) than have a roof full of >panels fail with no one around to fix them or replace them. >Tino >–
I’ll agree that retrofitting an existing home with active solar collectors is a questionable investment. However, as numerous people have pointed out, there are some very simple approaches to passive solar, like putting most of the windows on the south side of the house. However, I see little or no evidence of even the feeblest attempts on the part of builders to take advantage of the sun’s energy. I’ve seen houses with a great southern exposure that haven’t got a single south window in the main living area. — Duane Jacobson
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> Well, one has to add in the fact that local building codes often > forbid the use of certain styles of construction that would allow very cheap > passive solar systems. Remember that many of the good solar-heated designs > take a holistic perspective and would require a fundamental change in the > design of a house — like using an earth berm on one side of the house.
The problem with radical solutions like this is that more conservative solutions are nearly as good. At a recent home show here in Rochester, one of the 6 houses displayed was a 1700 sq. ft. "environmentally friendly" house. It did not look very different from a conventional house. If you looked closely, you would notice that the exterior walls are thicker, and maybe there were a few more windows on the south side (not that that helps much in Rochester…). The builders of this house promise (in writing) that it will cost no more than $200/winter to heat. That’s not bad in Rochester, where gas is fairly expensive (> 3 times the current spot market wholesale price) and the climate is brisk. Sure, maybe a geodesic/earth-covered/solar-festooned superhouse would use (say) $100/season. But it’s hardly worth it. Paul F. Dietz
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- Hide quoted text — Show quoted text ->>Also, I would have to add that if the existing solar technology in that >>house happens to be phased out, you’ve got a several hundred thousand >>dollar "experiment" on your hands. People buy houses for security, and >>don’t want to have to rebuild it 10-15 years down the line. >Maybe you could explain how passive solar technology is "phased out" >making your home less valuable? >I’ll stick to my gas bill (albeit a bit high) than have a roof full of >panels fail with no one around to fix them or replace them. >Tino >– > "Here are the young men, the weight on their shoulders…" – J.D. > Purdue University School of Nuclear Engineering
There seems to be a lot of confusion in this thread as to what constitutes PASSIVE and ACTIVE solar heating. Passive solar heating is accomplished by using certain heat-storing materials, putting glass in appropriate places, and orienting your house to optimize (maximize or minmize depending on your climate) the amount of solar energy warming the homestead. There are no panels, pipes, coolant, etc. involved in PASSIVE solar design. Gene Spears
Response:
>I just read a book written by the Hawkweed Group, a solar architectural >firm from Wisconsin. They make a claim that a passive solar house >can be built just as cheaply (or even cheaper) than a conventional house, >and that over 90% of the heating requirements of the house will be provided >by the sun.
No problem. I built a normal-looking house, except that most of the windows face the south side. On even the coldest days, if the sun is shining brightly I need no other source of heat. However, in this climate you would be hard pressed to rely on the sun for all your heat. During November this year, there were only 5 sunny days. And the sun is only reasonably high in the sky for a maximum of 8 hours. I guess that means that only 6% of the heating requirements for the month were met by solar. I’m afraid that for most people who need wintertime heating, the sun is not the answer. The reason it’s cold in the first place is that the sun’s heat is not strong enough. Move my house to Colorado and I’d do just fine, thank-you. Rolf Meier Mitel Corporation
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