Heliotrope: An Energy Positive Solar Home

[n2doc]

by Andrew Michler, 08/20/10



Look, up in the sky — it’s a bird, it’s a plane, it’s the Heliotrope! The brainchild of Architect Ralph Disch, this rotating solar home was the seed for the extraordinary Sonnenschiff Solar Development and the modern solar movement in Germany. The home takes full advantage of the sun by rotating with it, allowing daylight to course though its triple-pane windows and energize its large roof-mounted solar array and solar thermal pipes. The result is one of the first zero-energy modern homes in the world — one that actually ends up generating five times the energy it consumes.

Twenty-five years ago, when Ralph Disch’s hometown of Freiburg, Germany considered building a nuclear power plant built nearby, he fought vigorously to keep it from happening. As he applied his passion to finding an alternative, he looked to the sun. The resulting Helitrope home is a vigorous concept that makes incredible use of solar energy thanks to its kinetic design. Mounted on a pole, the home is timed to rotate 180 degrees through the day, following the sun’s track. The 6.6 kWH solar panels on top produce more than enough energy to make the home net energy positive. A unique hand railing system on the roof doubles as solar thermal tubing that heats the home’s water and radiators.

The home also re-uses greywater and rainwater for domestic use and features a composting toilet system. While the practicality of the home’s design may not have caught on, the principles behind it speak to a genuine revolution in sustainable design that many architects are only now starting to realize.



http://inhabitat.com/2010/08/20/heliotrope-the-worlds-first-energy-positive-solar-home/

[FBaggins]

1. Something there just doesn't add up.

a 6.6 kW (not kWH) capacity solar array doesn't supply all that much power. This home produces about 9,000 kWH/year... which averages out to one kW/hour. You can barely run a window A/C unit off of that... let alone an entire home.

When they're talking about creating five times as much energy as it uses, they must be comparing just to the power used to turn the thing (which might be 200W).

[kristopher]

2. Amazing how you can complete an equation with none of the necessary variables...

You wrote:

a 6.6 kW (not kWH) capacity solar array doesn't supply all that much power. This home produces about 9,000 kWH/year... which averages out to one kW/hour. You can barely run a window A/C unit off of that... let alone an entire home.

When they're talking about creating five times as much energy as it uses, they must be comparing just to the power used to turn the thing (which might be 200W).

You have no idea of the insolation, the efficiency of the panels nor the demand of the home's systems, yet you are magically able to conclude that the clearly stated benchmark in the article is false.

From the article:

The result is one of the first zero-energy modern homes in the world — one that actually ends up generating five times the energy it consumes.

The entire building design is relevant to the outcome, not just the feature maximizing energy harvesting. For example, note the design detail described - handrails that double as solar hot water collectors. Given your history of monovision support of nuclear energy, I'm sure it's this line that motivated you to attempt to smear that which you fear...

Twenty-five years ago, when Ralph Disch’s hometown of Freiburg, Germany considered building a nuclear power plant built nearby, he fought vigorously to keep it from happening. As he applied his passion to finding an alternative, he looked to the sun...

[FBaggins]

3. I never said that the benchmark was false.

I said that something doesn't add up.

You have no idea of the insolation, the efficiency of the panels nor the demand of the home's systems,

Nor do I need them. The home isn't brand new and they've stated how much it produces per year (9,000 kWH). You don't have to know the demands of the home's systems to correctly state that it's likely to use more electricity than a window A/C unit. If the home really produces all the electricity that it needs, then that says FAR more about how little they choose to live on (no TVs, no A/C, raw foods, and the willingness to go hours without power for days at a time) than it says about the solar array. I can also divide that average hourly number by five and compare that (~200W) to the amount of energy necessary to rotate the home itself (obviously an electrical motor).

You can easily build an energy-neutral home all on your own (and for far less than this home's ~$2million). I have two sitting in my basement right now. But there's a difference between saying "I can produce all the power you need for your lifestyle" and "you can cut your lifestyle close enough to zero for me to produce that much power"

Sorry if that was confusing for you.

[kristopher]

7. Playing fast and loose with the truth again???

You wrote, "When they're talking about creating five times as much energy as it uses, they must be comparing just to the power used to turn the thing (which might be 200W)."


"They must be comparing just to the power used to turn the thing" is unquestionably a statement that the benchmark they asserted is untrue. The term "zero energy home" has a specific meaning and your mischaracterization of their very clear meaning is typical of the mindset of nuclear supporters. You are attempting to create a false meaning that is more favorable to your view of the need for centralized inefficient power generation.

Large scale central power generation - whether from oil, nuclear or coal - is built around a marketing strategy that PROMOTES inefficient and wasteful use of electricity. The more they can sell, the more money they make. 9000kwh/yr is more than adequate for a very comfortable lifestyle. For instance, it is 4kwh/day MORE than the average home uses in California.

Your "nuclear at all costs" tunnel-vision is unquestionably impairing your faculties.

[FBaggins]

9. Poor reading comprehension on your part

does not equal dishonesty on mine.

But then again... since you seem to be shooting for a record of consecutive spam-free posts (double digits?), I shouldn't complain.

Large scale central power generation - whether from oil, nuclear or coal - is built around a marketing strategy that PROMOTES inefficient and wasteful use of electricity.

LoL! Exactly the opposite. It isn't that people's behavior is modified by the power companies... it's that the power companies design their network to meet the demands of the public. It is the alternative position that says people should adapt to whatever we can give them. It isn't as if the power companies decide "hey... we need to sell more power... let's start an ad campaign endcouraging people to set the thermostat lower during the summer and increase the heat in their pools this winter!" - and then there are all those credits that they offer for installing energy-efficient appliances (thus buying less from them in the future)... craft b@st@rds aren't they?

9000kwh/yr is more than adequate for a very comfortable lifestyle.

It CAN be... if you aren't turning a three-story home on its axis all day long and the home is small enough.

For instance, it is 4kwh/day MORE than the average home uses in California.

But nowhere near five times as much.

Your "nuclear at all costs" tunnel-vision is unquestionably impairing your faculties.

I have no such tunnel vision... I'm open to rapid expansion of all cleaner forms of power... but your "no nuclear regardless of the sacrifices in lives and environment that are necessary" is the blinding one.

The term "zero energy home" has a specific meaning

Not "a" specific meaning... but a number of them. Including one that allows them to buy all the grid energy they want as long as they buy it from a clean source. The article clearly intends to leave the reader with a different impression. The owner certainly isn't living disconnected from the grid and entirely self-sufficient for energy use (which many of the parallel articles intend you to come away believing).

[DCKit]

4. Well, it's got 5x more panels than our fixed-panel array...

which generates as much as 80 amp hours per day (without tracking the sun) and supplies 90% of our electricity year-round.

I think the math is accurate.

[Dead_Parrot]

11. Tracking, tracking...

This arrangement would give you a chunk more than 25% capacity, since it's shifting around to face the sun: 15MWh/yr says my envelope.

I don't have figures for Germany, but the average home use in NZ is around 11.5MWh/yr, and we probably have a similar use pattern: If it's a very efficient home, I can well imagine it producing a good 10Mwh/yr extra.

Of course, it'll cost the government thousands a year in subsidies, burn coal at night and looks like fucking mushroom, but that's Germans for you.

[thereismore]

5. Looks like the BP blowout preventer. nt

[Raster]

6. Actually it looks more like a BP well preventer.

[Dead_Parrot]

10. Boom-tish! nt

[pscot]

8. Gaudy

You can do a lot with large sums of cash.

[XemaSab]

12. I cannot see that word without being reminded of this pooem

I too once hoped to have a hoopoe
Wing its way within my scoopoe,
Crested, quick, and heliotroopoe,
Proud Upupa epops.

For what seemed an eternity
I sat upon a grassy sloopoe
Gazing through a telescoopoe
Weaving snares of finest roopoe
Fit for Upupa epops.

At last this message came to me
Inside a crusty enveloopoe.
It said, “Abandon hope, you doopoe.
The hoopoe is a misanthroopoe.”
Signed, Your far-off friend U.e.