ABC: Zero-energy homes becoming more popular.

[skids]

Jose and Marciala Reyes built a zero-energy home in Tucson, where solar power produces heat, air conditioning and even hot water. How much are the Reyes' monthly energy bills?

...

"We pay between, on the average, $20 to $28," said Jose Reyes, a retired businessman. Sometimes, their bills are as low as $5 a month — a savings of around $250 compared to others in their area.

...

Builders say solar power is perfect for the climate in Arizona, with its 340 days of sun each year. But in places like Oxford, Ohio, there is seldom any sun during the long winter, so residents are finding other alternatives to heating their homes.

Some are finding energy savings in a hole in the ground — that's where contractors are building geothermal power units. Loops of water-filled pipe are buried below the frost line. From there, they pass the earth's internal heat through a special furnace.

Contractor Bill Spade has never been busier installing the $15,000 units. "When you go from doing a couple of jobs a year to doing, like, four jobs a month, it's a big change," Spade said.

http://abcnews.go.com/WNT/Technology/story?id=1242381

[MADem]

1. Too cool!

The person who comes up with a retrofit system that is not onerous, not too expensive, can be placed in a NOT OBVIOUS location, and WORKS, will be rich, rich, rich.....

People are getting to the point where they would rather just SHELL OUT NOW, rather than get the drip, drip, drip of brutal energy bills.

[midnight armadillo]

3. There is already a way

It is not onerous, obvious, or expensive. It's called passive solar, and it can cut heating and cooling bills by 50% compared with conventional construction. All it requires is that the south side has a window area commensurate with the amount of thermal mass (stone, earth, plasters) inside the home, and that N/E/W views are limited. It doesn't make the house look funny or anything - many passive solar homes are difficult to tell as such by eye. The classic design is the New England saltbox home. This adds $0 to the cost of a home.

In passive solar, the summer sun is shaded out by overhangs and maybe trees, while the winter sun warms the interior. Hence the cost savings. Combine this with a draft-free, well-insulated construction method like SIPS and you'll pay a fraction for heating and cooling compared with neighbors, and you haven't even added cheap solar hot water yet...

One could also go further and build something like an earthship (www.earthship.org) that requires zero external utilities, but that's pretty radical. My ambition is to live in one someday, once I convince my wife ;-)

[MADem]

4. I'm waiting for something that can be slapped on an old stone house

in a historical district. I took a look at that sunball thing that they are doing in Australia, it will be interesting to see how that takes off--not big, pretty doggone sturdy, and up on a high roof, you wouldn't even see it!

[dcfirefighter]

5. For a retrofit

gutted, that is, i'd recommend the following:

sprayed on polyurethane foam (inside the stone walls)
geothermal exchange heat pump
hydronic floor heating, preferably on lightweight concrete floors, OTW on 'Warmboards'.
insulated duct central a/c
energy exchange ventilation
if possible, appropriately overhung south facing windows, OTW, deciduous trees (not oaks, they hold their leaves too long).
whatever solar hot water you could afford (during the summer the GSHP heats the DHW tank with the heat it removes from the home, during the winter it runs to heat the DHW when it's not heating the home)

[midnight armadillo]

6. But then you lose all that thermal mass!

While dcfirefighter's suggestions would result in a home with fantastically low energy bills, those big ole stone walls have too much mass to put outside the building's insulation (although a maintenance free exterior that'll last centuries does have something going for it!).

You could do a strawbale veneer on the outside of it instead, adding R-40ish inslation over the stone and leave the stone bare on the inside. Granted this may impinge on the home's historic character...but a nice limestone plaster on the strawbale may pass historical muster :-)



On edit: it is my cantankerous opinion that any home that requires massive external inputs of energy to be livable is one that is fundamentally flawed. In fact, I have a suspicion that rising energy costs will not only kill the 8,000 sq ft McMansion for a family of 4 but will also result in a return to regional architectural styles - those that are well-suited for their climates. Ex., adobe in Southwest, saltboxes & capes in NE, high ceilings/porches in the South, etc.

[dcfirefighter]

7. I like the idea of thermal mass

but it doesn't really reduce the energy inputs required - esp. if the windows arent situated for daytime winter solar heat gain. But I did include the concrete floors for that purpose.

Personally, I've always liked the look of rammed earth, but on the east coast, most of the midwest, and anywhere else where there isn't much of a diurnal temperature swing, the lack of insulation outweights the benefits of thermal mass. Even in the desert SW, it'd probably be a good idea to insulate the walls that don't receive sun.

I did see one company had figured a way to sandwich 4" of board insulation between two 12" rammed earth walls. I think it was a canadian company.

If I could afford 18" walls (e.g. not on a small lot or in a rowhome), I'd go for strawbale exterior walls with a big RE interior wall on slab. Actually, i'd like to ram a masonry heater in place within an earth wall.

While not quite as 'green' and certainly not as esoteric as adobe, strawbale, or rammed earth; I like ICF and SIP buildings. I especially like ICF in urban settings, if only for it's acoustic isolation properties. If buildings don't have party walls, SIPs are the way to go. If you want them 'greener' I think you could find them with soy-based insulation and pressed cellulose fiber boards (hemp?, ryegrass?).

[MADem]

8. I cannot gut this thing, the woodwork is incredible, the walls are over a

foot thick (there is brick under the stone); the ceilings are high, old, plastered!!! Plus, the historical society would have my ass and not let me do that--we are in the National Register!

I am waiting for those flexible solar panels, that can be rolled out like a rug, or that sunball from Australia...I just wish they would hurry the hell up and make that stuff commercially viable!!!!

What trees are best, in your opinion, for increasing efficiency?

[dcfirefighter]

9. you may be able to inject foam

for insulation, either behind the plaster, or btw the brick and stone. Even a little would help - you are mostly going for airtight walls. Most of your heat leaves through convection rather than conduction through insulation. Good vapor barrier (provided by injected foam), draft-free windows, and good attic insulation are your best bets.

As for trees, I'd find some native species that drop their leaves all at once. If you've got good south facing windows, and you're up north, don't put any trees on the south. A windbreak of evergreens, or even of varied height deciduous trees, on the north and west sides of your house will slow winds from stealing the heat from your home.

[MADem]

10. I am going for the good windows!!!!!!!!!!

And you are right, I probably need to do a bit better on the attic insulation, though it really isn't bad (the snow stays on the roof, the third floor is warm as toast with the radiators off, so the heat ain't gettin' out too much!).

The foam between the brick and granite is probably a nonstarter--they are butt up against one another, and the guy who built this house (he was a builder, and a good one for his time) built it like a fortress--it was an air raid shelter in the duck and cover days. I recently repointed the granite, that could well help--we'll see when the bills come in. It's just that the masonry tends to hold the cold, which is actually a good thing in summer (the interior of the house is really comfortable in the fine weather, except on the most brutal summer days, and even then it is probably fifteen degrees, minimum, cooler than the outside, and maybe a bit cooler still on the lower floor).

Actually, once I get it heated up, if I can just mitigate drafts, it stays pretty cozy. The windows are going in this month, and I am counting on them helping out in that regard. I am wanting to upgrade the doors as well, but I am no Roosevelt, and I do not go for E-Z credit, so I will start budgeting for that, as well. In the meantime, draft stoppers and keeping the vestibule doors closed will have to do!!!

I live in a very old neighborhood, with folks all round, very close by, in similar homes with small yards, but I need to replace some trees out front that are dying from this awful black spot crap that has infected the whole region. I am torn between evergreen screening (busy road--gotta worry about traffic fumes, winter salt on roads, that kind of stuff) and something deciduous, that would mitigate the summer sun. I do not know a damn thing about trees, and of course I also have to concern myself with the aesthetics of it all--not just for the sake of the neighbors, but for peace at home as well (a few lovable fussy types with strong opinions, but few suggestions!).

I am always looking for ways to pinch a silver dollar till the eagle shrieks! I've gone to fluorescent bulbs wherever I can get away with them, and they have done a good job of cutting the bill a bit. I also had to buy a new fridge when the old reliable finally died, and I got a super-efficient one with some nice bells and whistles.

Funny how priorities change--in my youth, I loved a new sports car, now I get a charge out of a space-age fridge!

[dcfirefighter]

11. Visit a local nursery

And get advice from them.

To start, consider a low evergreen privacy hedge along the road.

Look at trees with multi-season interest:
http://ohioline.osu.edu/hyg-fact/1000/1143.html
http://www.urbanext.uiuc.edu/hortihints/0204a.html
http://www.gardenlerner.com/multi.htm
http://landscaping.about.com/cs/treesshrubs/a/dogwood_trees_2.htm

or, depending on vehicular traffic, urban hardiness:
http://media.hgtv.com/HGTV/newsletter/gardening_newsletter/vol_011/GNL_031002.htm

I'd also consider fruit trees, either full size, semi-dwarf, or dwarf: spring blooms, summer shade, fall fruit, winter sun. Apple and cherry are particularly pretty.

[MADem]

12. Hey, thanks for those links, those will help me a lot! nt

[expatriot]

2. I live in the sunniest zip code in the country and solar energy is foriegn

Yuma, AZ
you'd think there'd be solar panel farms all around here but there are hardly any solar powered homes in town at all.

http://verticals.yahoo.com/cities/categories/sunnydays.html