How this actually works is quite simple when compared to a thermos bottle, since a thermos is so well insulated the contents retain most of its heat, sidestepping the need to constantly produce new heat to keep the contents warm. Same as a Passive House.

Given the high insulation levels and air-tightness of a Passive House, it requires almost no active energy to create indoor heat, it is most often sufficient enough for the ‘contents’ (occupants, light bulbs, and appliances) to generate enough heat for the home to remain perfectly comfortable.

Also, without an expensive or complicated central heating system, this cost savings offsets the cost of construction, making a Passive House the most economical choice of all the green building methods out there today.

To illustrate the point about heating, the first image below is a thermal image of a coffee maker,  representing any home with an “active”  central heating system required to keep it warm and comfortable. The red, yellow and green indicate varying degrees of heat loss from the container. The second thermal image is of a thermos, where through “passive” insulation and airtightness the contents can easily retain the heat, you’ll notice no color other than blue, which represents coolness (ie no heat loss).

Building a house with no central heating system can sound risky, but you can see how simply elegant and intelligent it is once you imagine putting your resources into the passive components such as the insulation, air sealing, super efficient windows and a small air handling system for fresh air.

It’s hard to resist the lure of energy independence and a Passive House puts a person well on their way!

Authored by Jefferson Kolle, in the March edition, Fine Homebuilding did a great job featuring two new Passive House projects, one  in Massachusetts and one in Minnesota. The Minnesota project employed the use of other renewable resources, such as a photovoltaic system, to get the Passive House in a net-zero mode. Both of these projects are aesthetically beautiful homes.

The article is really a superb summary of the Passive House standard. It begins with a brief description of Passive House and covers a bit of the history. The author went on to cover the salient parts of the building envelop and air handling system. He effectively covers the Passive House Planning Package (PHPP) modeling software used to remove the guesswork of performance results once the project is complete. Finally, he talks about getting accredited as a Certified Passive House Consultant.

This is an excellent piece, and concisely written. This article very effectively puts the Passive House concept into a nutshell. Complete with project photos and a labeled cutaway wall section.

The article (.pdf) can be downloaded from the Passive House US (PHIUS) website. The article is called: “The Passive House, Green without Gizmos”

Tessa, our designer, wrote a little editorial on the subject:

“Are the materials to build a Passive House the same as a traditional house?” Emphatically yes!  That is the beauty of the approach, it is open to developing technologies, but entirely achievable with common place American building materials.  The simple answer is we just end up using a bit more of those ordinary materials such as insulation and framing.  It is easy to think that a Passive House, with its 90% reduction in energy use, would employ outlandish technology, hovering tools and beams of alien light, but that is not the case.

Construction is similar in process and even material choice, the only variance being the extra care and testing taken for air tightness requirements and longevity.  The wall could still very well be composed of studs, insulation, sheathing and drywall.  How they are arranged in the assembly is where you will see the biggest difference, for example, you might have a double stud wall to eliminate thermal bridging, deeper and filled with more insulation.  The sheathing would likely be on the interior under the drywall.  Then an open diffusion fiber board would occur on the exterior of the wall in conjunction with a rain screen siding application, et Voila!  The 200 year house is born, no alien technology required.  The same kind of thinking gets applied to other assemblies and components of a Passive House, floors, roofs, etc.  Two of the places you will see a bigger difference in “typical” construction materials is the mechanical system, Heat or Energy Recovery Ventilators being the choice of the day for fresh air delivery and in some cases even space conditioning delivery.  The other being specific high performance Passive windows, it’s still looks like a typical window mind you, it is just substantially better performing.

The energy performance is the standard, how you get there is up to you, your budget, your location, your network and expertise, it is the advantage of a holistic approach.  The Germans have a larger Passive House Market than we do, and subsequently they have many construction means and methods being developed specifically to reduce cost and speed up construction, once our American market is flooded with Passive House’s we will see those same kind of leaps and strides in progress.

One of my Passive House clients and I were chatting the other day, and being intelligent, informed and excited about his own Passive House in the design process he stated, “You can drive a hybrid, or you can just not drive at all!”  In other words, you can toss technology at the “problem” or you can eliminate the problem. Passive House design simply eliminates problems.

See full Wikipedia post.

Passive House History

The Passive House standard originated from a conversation in May 1988 between Professors Bo Adamson of Lund University, Sweden, and Wolfgang Feist of the Institut für Wohnen und Umwelt (Institute for Housing and the Environment ). Their concept was developed through a number of research projects , aided by financial assistance from the German state of Hesse. The eventual building of four row houses (also known as terraced houses or town homes) was designed for four private clients by architects professor Bott, Ridder and Westermeyer.

The first Passivhaus buildings were built in Darmstadt, Germany, in 1990, and occupied the following year. In September 1996 the Passivhaus-Institut was founded in Darmstadt to promote and control the standard. Since then, thousands of Passive Houses have been built, to an estimate of 15,000 currently most of them in Germany and Austria, with others in various countries worldwide.

After the concept had been validated at Darmstadt, with space heating 90% less than required for a standard new building of the time, the ‘Economical Passive Houses Working Group’ was created in 1996. This developed the planning package (modeling software) and initiated the production of the novel components that had been used, notably the windows and the high-efficiency ventilation systems. Meanwhile further passive houses were built in Stuttgart (1993), Naumburg, Hesse, Wiesbaden, and Cologne (1997) .

The products developed for the Passivhaus were further commercialized during and following the European Union sponsored CEPHEUS* project, which proved the concept in 5 European countries over the winter of 2000-2001.

In North America the first Passivhaus was built in Urbana, Illinois in 2003,  and the first to be certified was built near Bemidji, Minnesota in Waldsee, the German camp of the Concordia Language Villages in 2006.
The world’s first standardised pre-fabricated passive house was built in Ireland in 2005 by Scandinavian Homes, a Swedish company that has since also built passive houses in England and Poland.

*Mike Karnegis, one of the primary leaders in Passive House in this country, confirmed for me that the Wikipedia information is accurate.

This is a link to a short article in USA Today. It’s about a recently certified Passive House in Salt Lake City. Passive House design can take on many architectural styles to suit the varied tastes out there, (note the Portland Remodel post), this Salt Lake house embodies a clean simplicity that ‘feels’ good to look at.

The homeowners started a project blog that is fun to look at, especially the performance numbers if you are into that sort of thing. One of the primary numbers Passive House nerds like to discuss is ‘how many ACH?’ which translates to “How many air changes per hour go through the house when a blower door test is conducted at 50 pascals”… this one comes in at .47… not bad.

To learn more about passive house design please visit the Passive House Institute US.

For clarity, there’s a Passive House and there’s a passive solar house (what I described above goes with the latter). A Passive House is designed and built to exacting standards, performance tested, then certified versus a passive solar house built to take advantage of the sunshine that we don’t have.

Here we go, in a nutshell.

Passive House: Passive House, is an approach to design and construction that relies on a super efficient envelope, essentially minimizing losses to optimize gains (like body heat, cooking heat, and drying clothes), with a super efficient envelope, you get to keep all that heat.  There is a component of optimizing solar gains to Passive House, it shares this in common with the solar movement, but its primary focus is conservation and minimizing of energy demands. The Passive approach yields (in any climate with any level of exposure, I might add) 75%-90% more efficient structures, combine this with the other elements necessary to a Passive House, like ample fresh air delivery, and high performing windows, you end up with a substantially more comfortable, affordable and healthy house.

Passive solar house: Passive solar houses rely on optimal orientation to collect the sun’s heat, large thermal masses to store that heat, and climates with dramatic diurnal swings.  The caveat to the approach is that we  don’t all have ideal sun exposures, and suitable climates, not to mention that those windows that let the heat in, will also let the heat out.

When I was studying building science in school, back in the mid 80’s, I happened to live in Colorado where they get 370 days of sunshine per year, and lots of snow… a wonderful venue for applying passive solar. I remember one field trip where we went to a home that was built to maximize solar gain and had sufficient thermal mass that the home had a year round temperature swing of 4 degrees. Pretty impressive. Colorado is the mecca where passive solar design really shines, forgive the pun.

Now, the Passive House design standards allow all the non-mecca states to achieve a level of passive comfort unheard of in the building trades. Noteworthy is the outstanding payback period of an upgrade to Passive House standards. In most cases, it’s under 6 years.

That’s the very basic difference between the two. Hope that clarifies things for some of you, if you have questions, leave a comment or give us a call!

Passive House Design by Tessa Smith

(If you are up on these standards, skip this note in italics: Passive House standards, out of Germany, are the most rigorous energy efficiency building standards in the industry today (not to be confused with a passive solar home). A home built to Passive House standards can be certified once the completed building performance is measured and verified. As a result of energy efficient design,  a Passive House does  not need  a central heating system, it can be heated by the occupants and appliances within. In most cases, the heating energy costs are cut by 75-90% compared to a comparable code built home.)

The momentum that is occurring with Passive House Design is remarkable. We had an opportunity to view  Passive House designs by other designers in our region; it was stimulating to see the variety of styles. We also presented three designs that we currently have in development, see the images on this page.

The subjects presented were a splendid cross section of the most critical pieces of what goes into designing a Passive House and the kick off speaker was Katrin Klingenberg, Executive and Technical Director of the Passive House Institute US (PHIUS), she gave a perfect overview of all things Passive House, which got us all in the right frame of mind. The  other topics covered were about structural considerations, air infiltration, window technologies, HVAC, environmental impacts, the software used to model Passive House design and rounding out the day was a contractor from Oregon who is in the process of wrapping up the construction of a Passive House. Real world information.. we all loved that!

Passive House design is certainly at the leading edge of the evolution of energy efficient building design. No doubt about that.

Zeta

A couple weeks ago, while flipping through the Green Source Magazine, I turned a page and saw the picture below, I knew instantly who was in that picture. It was fun to discover that Mike Reynolds is still going strong.

One Man’s Trash. . .

Reprinted from Green Source Magazine

Interview by Aleksandr Bierig

Soon after Mike Reynolds graduated from architecture school in 1969, he disregarded much of what he had been taught and began a 30-year practice of building “earthships”—off-the-grid dwellings built from what the rest of society deems garbage (discarded cans, bottles, and tires, among other items). His radical and unusual structures have received resistance from zoning and code legislations, spurring a continuing struggle to change the building permit process.

GreenSource: You have said that right after architecture school, you began to feel that the architectural field was “worthless.” How did you arrive at that conclusion?

Reynolds: I was trained as a conventional architect and was taught about 2-by-4s and bricks and flamboyant artistic ideas about design. I also learned to turn the heating and air-conditioning and electrical and plumbing over to an engineer. Since then I’ve discovered that a building in today’s world is a machine that has to be designed by someone who understands all of its layers.

GS: Your operation seems to involve a lot of trial and error.

MR: I think one of the major factors is that we’re not respecting is failure. We’re not going to learn anything from doing everything right. You can do the math, you can do the design, you can figure something out to a T, but in nature there are circumstances and nuances that can make things work different ways. Right now, the architectural community does not allow failure—you get sued or you lose your license, both of which I’ve done.

GS: Can you describe an instance where you’ve failed at something and the lessons you learned from that episode?

MR: Well, when you take a roof that, in conventional architecture, is meant to shed water, and you turn that roof into a basin to collect water, its whole nature changes. You can make a minor mistake on a steep roof that sheds water and not have a crisis, but if you make a minor mistake on a roof that is a basin to collect water, then you have a crisis.

GS: Do you feel that at this point the earthship model has those problems worked out?

MR: I’ve been failing at things for so long that now I have tuned it to the point where it is actually more reliable than a conventional building in many ways. We have a product now that can be adjusted for any climate.

GS: Is your method the only effective sustainable building practice you’ve seen, or can you suggest other approaches that have inspired your work?

MR: The inspiration comes from animals and plants. The tree is a mechanism that I model a lot of my thinking on. It’s got built-in water harvesting; it’s got built-in energy harvesting; it’s got everything. Its relationship to the earth is really a great model.

GS: What about the aesthetic character of the earthships?Is there an intention or do you see it as driven purely by function?

MR: The core of the building design is driven by function: There’s no question about that. Once we get it working, then we can play with the looks. Looks and aesthetics end up getting into economics and value, too. We have a very straightforward version that is really a product of function, and we have taken that and have decorated it and played with it and sculpted it. But my point is that there is no sense in sculpting a beautiful ship that doesn’t float.

This article appeared in the January 2010 print issue of GreenSource Magazine. Subscribe to GreenSource in print

Enjoy!

Zeta

Ps. I’m currently on the road with my husband, Randy, and dog, Eddy. Yesterday we visited the town of Rhyolite, a ghost town near Death Valley that had sprung up in the early 1900’s as a gold mining town. In Rhyolite, we discovered a home built in 1906, made of… bottles and concrete! I took some pictures and will make a post in the next couple days. It’s all so interesting!

Christian Science Monitor. Click here to link to the original article.

By Husna Haq Correspondent / February 22, 2010

It’s being hailed as the Holy Grail of clean energy: a refrigerator-sized personal power plant that produces energy cheaply and cleanly and may one day replace the traditional power grid. Its inventor wants to put one in every home by 2020.

Bloom Box is the creation of Bloom Energy, a Sunnyvale, California-based company that is promising to revolutionize energy with its “power plant in a box.” K.R. Sridhar, CEO of Bloom Energy, gave Americans their first peek at the new device Sunday on CBS’s 60 Minutes. On Wednesday, Mr. Sridhar will make a major public announcement in Silicon Valley unveiling Bloom Box.

So what is Bloom Box?

It’s a collection of fuel cells – skinny batteries – that use oxygen and fuel to create electricity with no emissions.

Fuel cells are the building blocks of the Bloom Box. They’re made of sand that is baked into diskette-sized ceramic squares and painted with green and black ink. Each fuel cell has the potential to power one light bulb. The fuel cells are stacked into brick-sized towers sandwiched with metal alloy plates.

The fuel cell stacks are housed in a refrigerator-sized unit – the Bloom Box. Oxygen is drawn into one side of the unit, and fuel (fossil-fuel, bio-fuel, or even solar power can be used) is fed into the other side. The two combine within the cell and produce a chemical reaction that creates energy with no burning, no combustion, and no power lines.

About 64 stacks of fuel cells could power a small business like a Starbucks franchise, according to Sridhar’s 60 Minutes interview.

Working with an investment of around $400 million, aerospace engineer K.R. Sridhar spent close to a decade inventing the Bloom Box. It grew, he explained to 60 Minutes, from a device he originally invented to produce oxygen on Mars. When NASA scrapped the Mars mission, Sridhar reversed his Mars machine, pumping oxygen in, instead of making oxygen, he said.

Sridhar already has some 20 well-known customers, including Google, FedEx, Walmart, Staples, and Ebay. The corporate boxes cost about $700,000 to $800,000.

Ebay installed five Bloom Boxes nine months ago, and they fuel about 15 percent of its San Jose campus, said CEO John Donahoe in the 60 Minutes interview. “It’s been very successful thus far,” Mr. Donahoe says, adding that the company has saved $100,000 in electricity costs already.

Former Secretary of State Colin Powell is also on Bloom Energy’s board of directors.

But the Bloom Box isn’t without skeptics.

Michael Kanellos, editor of Greentech Media, which covers the clean energy market, says Bloom Energy isn’t the first company to claim it has invented a clean energy fuel cell. Cost is always a concern with fuel cells, as is round-the-clock, 24-7 functionality. Bloom Energy still has to figure out how to mass-produce the unit and get its costs down low enough to outfit every home with a Bloom Box, Mr. Kanellos said on 60 Minutes.

Sridhar says he eventually wants to get costs down to $2,000 per box.

Bloom Energy has also been cryptically silent about its new device. As of Monday, its puzzling website has no information about the Bloom Box, and the company has not replied to multiple requests for interviews.

Still, Sridhar has ambitious goals for his Bloom Box, planning not only to place it in every American home in 10 years, but also in homes in Africa, India, and China. He’d like to start, he says, with America’s first family.

“I want a Bloom Box next to the [White House] organic vegetable garden,” he says on 60 Minutes. “It’s about seeing the world as what it can be.”

The site features exclusive content written by experienced working professionals from across the nation, many architects, designers and other industry folks.

The first page opens up with a rolling set of relevant and provocative questions all pertaining to some aspect of green buildings, such as:

• “Without a dedicated heating sourced in a Passive House, will I stay warm enough in our cold and humid winters?”
• “I am just starting to design a home and want to incorporate GREEN things. Do I start now or wait until I start working with a builder?”
• “Are there any manufacturers of non-toxic, non off-gassing bathroom vanities? Are there any non toxic glues for bathroom tiles?”
• “How many south facing windows for a 100% Passive House?”
• “Our aluminum-frame windows are harboring condensation and mold. Can you recommend window solutions for a damp environment?”

Other types of information come in the form of articles written about such subjects as “Creating a Green Kitchen: From Resource Planning to Maintenance“, “Selecting Green Paint”, “9 Ways to Make Your Home More Energy-Efficient”, and “Choosing Green Kitchen Countertops: Our Top Picks” to name a few.

There is also a handy directory of green building professionals, searchable by business name, city, state and/or zip code.

It seems to me, the audience for this site, is someone who is getting their feet wet in the world of green building for the first time. The information is manageable, not technical, relevant to regular people, and it covers a lot of ground while exposing the viewer to the concepts of green buildings and energy efficiency.

From here, they will have a good foundation on which to expand their awareness as they seek out new sources of information.

Green Home Guide. Check ‘em out.

Enjoy!

Zeta