Solar hybrid house designs

Quelle surprise...

Estate agents...another bunch of leaches who bring nothing to the table!

They should have learned how the house worked and then 'sold' the concept along with the house!....

I get sick of salesmen who want to sell Rolls Royces for the price of Minis....and think they're clever to be able to do it!

Del is correct if it takes a little effort to learn how to handle a system that takes more effort than turning a thermostat then the average joe will panic -but this will be the same person that cries about their utility bills and gets their shorts in a bind over global warming!!

Most of the really good books on alternative house building have a section on the trials of getting a mortgage, or even meeting building codes.

The folks who design "Earthships" actually sell videos to be shown to the concerned parties.

Weird? I would call it weird also. People buy houses to express themselves, as well as live in. A person does not need a massive mansion to live in. They seek status.

If status is the issue and letting people know that you are "powerful" and "worth" a lot of money (read, a valuable person), then building a house that saves a few bucks on heating defeats the purpose. I think it is a failure of the architect to understand basic human nature and the market.

Any house that looks "solar" to save a buck will fail because it says you cannot afford it and you are cheap. Anything that looks like a solar engineering experiment (PV panels, for example) will also fail. Any house that is dependent on direction relative to N-S, E-W will also fail. All of the designs on enertia.com violate basic real estate principals and human nature, and therefore should be considered "weird" or off base.

The theory of passive solar is, in a word, wrong. The idea mentioned on enertia.com about using wood in a phase change is better than typical passive storage because you can store energy at a constant temperature, whereas concrete or water must get hotter (BTU/LB/F) to store any energy over the set point (typicially 72F in a house). But where is the phase change set point?

Another fatal flaw is the notion that a living space can be flooded with solar radiation to absorb the energy internal to the building. One would have to wear a Mexican hat to actually live in such a "house" if you can call it that. Any space that has direct sun is NOT usable while the sun is there. That sun also will quickly fade and damage furnishings which is unacceptable for anybody who has furniture better than a Wal-mart special grade.

Think of passive solar like building a car that weighs 20,000 lbs, vs a car that weighs 500-1000 lbs. When you want the temperature at a point different than the "natural" temperature, "we have a problem Houston", big time. What if you are sick and want the temperature at 80F and not 72, or you want to chill at 63 F on a hot summer day in a bedroom? You are out of luck. The thermal inertia is very difficult to overcome, not to mention there is no way to move the temperature, and the cooler/heater that would be needed is massive, which defeats the purpose.

I would suggest to you that an "envelope" house (old concept) is also very expensive and very difficult to get by inspectors.

A guy I know who has done passive solar for 30 years sat down with me for 1/2 hour and I was able to convince him that the entire theory of passive solar is fatally flawed. He just went along with the "doctrine" of passive solar like it was somehow true, and never questioned the theory, even after 30 years.

The construction industry has their brains in off mode and they get real pissed off if someone brings out new technology. Go ask a major house building what would happen if someone had a technology that can look like whatever the customer wants, big or small, be on cost par with stick, and provide heating and cooling and perhaps electrical. They get pissed and want to riff off the ideas. Most claim that the "code" will not allow it.

The code addresses five main things: energy, wind, seismic, flood, and fire. Each must be addressed or the project fails. A 2000 sft house should be able to produce around 25 kw during a sunny day. PVs would cost more than the house. A typical house burns 4-8 gallons of gasoline equivalent per day, 365. It is typically more than two cars driven 50 miles round trip per day. A house should be able to power the car for the 50 miles/day typical, leaving a person with near zero need for liquid fuel most of the year.

In short, our energy solutions, like most things, start in the "home" and not with government this or that. We only need 1 in 4 houses to generate all the electrical power needed to run a city.

I´m an architect and i work for a long time in passive and active solar design... and, you must be more clear. A house must function, but the aesthetic is fundamental. As architects we must know how to compromise this too important artistic issues!!!

Guest,

How should I be more specific?

The theory of passive solar is that mass in a building can store heat according to the heat capacity of the materials. By having enough glazing at the right mass ratio with shading according to solar angles, one can add heat (solar gain) to make the house approach thermal neutral point. The idea is to store the heat during the day and release it during the night. To achieve this, south facing glazing (in north climate) is generally large and west glazing is minimized. In effect the house gets trapped by the solar requirements.

The same type of thing happens in manufactured and modular homes, but instead of the sun being the constraint, the road shipping limits constrain the house design. One can see these constraints very easily in the look of the house, less so with modular homes though. The lowest "level" or status of living is a trailer park (a cheap manufactured house), next a manufatured house, next a modular home track home, then a stick track home, and then a "custom" home. The trick is to make all look like a "custom" home and move beyond the constraint imposed by the road or, in the case of solar, the sun. For some reason people don't like to live in a house that is exactly like another person's house, even though they don't mind driving a car that is nearly identical to the next guy's car. Strange, but true.

My theory is that thermal inertia is NOT what is wanted in a building, just like mass inertia is not wanted in a car any more than is needed. Temperature (house) is speed (car). If a building looses power, for example, for a day or two, and the heat is lost, it then takes either a long time or a large power source to get the temperature up to speed.

Put another way, a friend of mind has a log cabin in the mountains. He only uses it once every other weekend. Because of the "thermal mass" it takes over 24 hours before the place actually heats up to a point that the walls don't feel cold. So half his time in the expensive/rustic log cabin is spent chilled with the furnace blasting. By about the time he is ready to go home the building has come up to temperature. If he lived there 24/7, then the inertia is not as bad, but in this case, the inertia wastes(!) a massive amount of fuel for a 48 hour stay. If the building had little inertia, it would heat up quickly, and once the weekend is over, the heat can be turned down to a level to keep the pipes from freezing. All the the inertia is a waste, just like a massive truck that accelerates and then puts the brakes on wastes fuel (without regen braking). The basic concept is the same.

The question then becomes: how to capture the heat to store it for heating/cooling over time, say 7-14 days, depending on climate, so as to minimize and/or eliminate the need for a heater, and to uncouple the house design from the constraints of the sun. If you do that, you can save 1/3 - 1/2 of the fuel used in the world, if not more.... Most of our fuel, and hence co2 ("a good thing") emissions, come from industrial processing, heating and cooling, and not from transit.

Is this what you asked? What kind of passive and active solar have you done?