Forget hybrid cars. Spring for a hybrid house.

May 17, 2007 11:03 AM

Enertiais producing "innovative new homes of remarkable strength, economy, and beauty, brought to life by an elegant new architecture and the discovery of a new source of pollution-free energy." The design took first prize in the Modern Marvels/Invent Now competition (previously). In an interview, the inventor, Michael Sykes, says "he was inspired by the way the earth’s own atmosphere keeps the planet at a relatively constant comfortable temperature despite the frigidity of space." He also notes that his wife calls herself a "homemaker," natch.
posted by pithy comment (17 comments total)

Here solar heated air circulates, pumping and boosting geothermal energy from beneath the house, storing it in the massive wood walls. Thermal inertia causes the house to "float" between the cycles of night and day, and even between the seasons.

Great concept, but "massive wood walls"? First of all, wood is not particularly known for it's thermal inertia--why not use tanks of water or build out of stone/concrete (both also fireproof)? Second of all, is using *more* wood really environmental?
posted by DU at 11:16 AM on May 17, 2007

The wood is an insulator, the air spaces provide the thermal inertia. These are pretty neat houses, I'd like to see the one in Green Bay WI and find out how it holds up in the winter months.
posted by substrate at 11:19 AM on May 17, 2007

Pepsi green.

Houses like these will only get built in the suburbs, where people will continue driving their Suburbans five miles to get a quart of milk, offsetting any environmental benefit the house might bring.
posted by adamrice at 11:32 AM on May 17, 2007

Houses like these will only get built in the suburbs, where people will continue driving their Suburbans five miles to get a quart of milk, offsetting any environmental benefit the house might bring.

Please, do tell us more.
posted by jimmythefish at 11:38 AM on May 17, 2007

The claim is that the resin in the yellow pine goes through a "phase shift" from liquid to solid and back, giving it more thremal inertia. I'm not sure I get it though.

But using wood is fine. It can be sustainably farmed, and should be sitting in that building for a long time. If the building is torn down, the wood can be reused.

I'm curious what it's like to live with double walls. I'd welcome the soundproofing, but is it easy to open a window?

Houses like these will only get built in the suburbs

Houses will continue to be built in the suburbs anyway, whether they be green or McMansions. And I don't see why this technology couldn't be applied to city three-flats and rowhouses.
posted by hydrophonic at 11:42 AM on May 17, 2007

Houses will continue to be built in the suburbs anyway.

Exactly. It's a start, and we need more of this.
posted by jimmythefish at 11:44 AM on May 17, 2007

..the air spaces provide the thermal inertia.

That's even worse than wood. Why don't they at least claim the foundation is the thermal interia component?
posted by DU at 11:48 AM on May 17, 2007

They have a (nearly) double-height basement, so they do use the basement as a thermal mass. The double-wall 'envelope' is for circulating that air, and the wood is, oh hell it's wood why do we care?
posted by Skorgu at 12:17 PM on May 17, 2007

I like the idea, but the model homes shown are al freakin' huge. Can these work on a smaller scale? They also don't seem especially well suited for the city or anywhere with actual weather.

(The opinions expressed here are strictly for entertainment purposes and are not those a structural engineer)
posted by lekvar at 12:22 PM on May 17, 2007

DU: It might have helped if you had read the linked interview:

DP: What do the critics say?

Two questions always come up. First, there is a group that thinks using wood for houses is bad for the environment — that using trees for any reason is bad.

Actually, nothing could be further from the truth. Wood is the only structural building material that is renewed on a scale vast enough to assure there will always be more than needed. And all of our wood comes from tree farms. No virgin wood was harmed to build this house!

There is also a large group that thinks that using wood for energy is good only if you burn the wood or distill it into ethanol or biodiesel. Again, nothing could be further from the truth; when you burn the wood, or wood-distilled liquid or gas, you release the carbon dioxide again.

Second, I often hear: “Concrete, brick, and stone are better for storing heat energy.”

They do store energy — but only *specific* energy, which means that as energy is put into the stone, brick, or concrete, the materials get hotter. While wood stores some specific energy, it also stores latent energy, which means the temperature is constant while the wood resins, lignins and cellulose goes through a phase-change. Luckily, that temperature is around 70 degrees F. In a house, you want the temperature to be constant.
posted by bove at 12:26 PM on May 17, 2007

The claim is that the resin in the yellow pine goes through a "phase shift" from liquid to solid and back...

The phase shift here looks to me like a time phase, not a state-of-matter phase. I read it to say that instead of giving off heat when its hot and absorbing it when it's cold, it starts giving off heat after a time delay, and this smooths out the temperature during the day.

The thing with 'crystals' does make it sound kind of woo-woo. Any scientists out there that can discuss the phase shift due to the resin, with or without the crystals?
posted by MtDewd at 12:40 PM on May 17, 2007

My initial reaction was that the whole Enertia(tm) (my god is that a terrible name) site reeks of snake-oil. Might be the tone it's written in, which reads like TimeCube as rewritten by a marketing hack, or it might be the seeming unwillingness to actually explain the principles at work without throwing around the aforementioned horrible trademark. However, the south-facing solar heat collector part at least sounds pretty workable--one of the Hemming's Auto Blog writers built a solar garage heater out of old pop cans using the same principle, and he claims it works pretty well. As far as I'm concerned, though, the jury's still out on the magical properties of yellow pine he's claiming--anyone better informed than me have any input?
posted by arto at 1:36 PM on May 17, 2007

What seems to be novel about "Inertia" are the double walls and the remarkable claims about the thermal properties of that wood.

The principle ideas here, passive solar, thermal mass, groundsource heat exchange, and designing for airflow have been around for awhile. Just look at their sources--we figured most of this stuff out in the 70's, and a lot more of us would be living this way now if Reagan hadn't taken the solar panels off the White House roof and effectively put the kibbosh on the green building movement.
posted by hydrophonic at 2:34 PM on May 17, 2007

It should be pointed out that the double walls, a Trombe wall on the south combined with a conventional air plenum, or envelope design, isn't new either. These are all pretty straight forward passive solar design ideas. Seems strange to see this win an innovation award.
posted by xod at 2:53 PM on May 17, 2007

The smallest 1000 sqft model is $60,000 and they say final costs are 3x to 4x times. That is $240 sqft which seems pretty high.
posted by stbalbach at 3:12 PM on May 17, 2007

Yeah, the website's copy is a little odd ...

The Sun, by photosynthesis, will have re-created the fast-growing material from which the home is made, in less than the time it takes to read this page.
posted by Alt F4 at 3:14 PM on May 17, 2007

Seems strange to see this win an innovation award.

Perhaps it's the combination of technologies plus whatever novel aspects there are that won the award.

I agree that the site's copy needs some serious help though. The concepts seem reasonably sound, but the whole tone makes it seem as though it's kin to the Q-ray thing.
posted by Zinger at 10:37 PM on May 17, 2007