Nabih Tahan on Passive Houses and European Home Building

Nabih Tahan's passive house remodel in Berkeley
Nabih Tahan's passive house remodel in Berkeley

Last night BuildItGreen’s South Bay Professional Guild hosted Nabih Tahan, a Berkeley-based architect who was recently featured in a New York Times article on passive houses. Nabih discussed the passive house concept and how it is being applied in Germany and the rest of Europe, as well as his experience building Low Energy Houses (Niedrigenergiehaus – the generation of homes before the passive houses) in Austria and remodeling his conventional house in the Berkeley flatlands into a passive house.

The term “passive house” reflects the concept that these houses do not have heaters to provide warmth. Instead, they  “passively” recover heat from all the other activities in the home – such as cooking, lighting, and even human activity. To enable this, a passive house is highly insulated, with an airtight building envelope, so that no heat can escape. To keep the air quality high, passive houses use “heat recovery ventilators” or “energy recovery ventilators” with air-to-air heat exchangers to constantly replace the old inside air with new outside air, while keeping the heat from the old air inside.

Passive houses typically use about 80% less energy for heating and cooling than conventionally-built houses.

(See more about passive houses in this post on my blog, and the Passive House Insitute U.S.’s web site.)

Tahan’s talk covered a huge amount of ground. Some of the high points included:

  • A description, with a number of photos and a video, of the current German and Austrian technologies for building houses and multi-family residences. These homes are built in factories, by automated, computer-controlled machines, and assembled in a few days on site. Because all the pieces are designed to high tolerances, the building sites are very quiet – if you hear a power saw on one of these sites, you know someone made a mistake.
  • He showed a picture of “model home mall” in Austria (here’s something similar in Germany – in German), where more than 40 of these pre-built home builders have built 80 model homes that you can tour. The homes range in size and style from modest single family houses to large mini-mansions, to apartment buildings.
  • I asked what one change in the U.S. would make it easier to build passive houses here. He said better windows and doors. Insulated and well-sealed windows and doors, often with triple-glazing and special coatings on the glass, comprise a key component of passive houses in terms of keeping the building envelope airtight. There are many manufacturers of these components in Germany and the rest of Europe, but none to very few in the States. In fact, Tahan is currently in discussions with investors on starting a factory to build these components, in partnership with an Austrian company.
  • For his Berkeley house, he decided to work with a U.S. supplier, Sierra Pacific, to demonstrate that the passive house standard is possible in the California climate with local products. In any case, buying the windows in Austria would have cost less than buying them here, but the cost of shipping would have made the Austrian windows more expensive.
  • In building a passive house, airtightness is as important as the insulation – they work hand in hand. And it’s the most difficult part, especially in the United States where buildings are not constructed by computer-controlled machines.
  • In Europe, building a passive house costs 4-5% more than conventional construction, but it saves 80% of the energy. Currently it’s a somewhat bigger premium to build a passive house in the States, due to lack of suppliers and know-how.

The passive house concept and approach is clearly a component of a zero-net energy home program. Reducing the amount of energy a home uses means it’s a lot easier and cheaper to generate that energy onsite. Architects like Tahan will be a key enabler of getting to the [intlink id=”329″ type=”post”]2018 goal of 100% zero net energy homes in California[/intlink].

This was an excellent talk, and I’m looking forward to hearing more from Nabih Tahan, and attending more BuildItGreen functions. If they’re all at this level, they’ll be a great resource for getting California to the goal of 100% zero net energy new houses by 2018.

Update (2/13/09): Nabih tells me that the Passive House California Group has just set up their website, where you can read about their next group meeting and other topics.

Green Building Salon – A Few Conclusions

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Perception is reality when it comes to green energy (image by striatic, CC 2.0 license)

I was thinking about what we accomplished/learned at our initial green building/green energy salon a few days ago, and came up with a few top candidates:

  • Liability – this is one of the biggest issues at the front of mind for builders and architects – they have to guarantee their buildings, and that makes them very wary of new technologies. One big challenge for green building will be coming up with ways to break through that barrier (the other alternative, of course, is to wait long enough that the new technologies prove themselves – but even this needs to be optimized). For example, perhaps the government could help take on some of the liability to reduce the risk for architects and builders trying to do the right thing.
  • Perception – Silicon Valley, as one of the attendees pointed out, is way ahead of the rest of the nation in terms of our perception that “green is just an obvious thing to do.” The general idea that green is more expensive or that it requires privation is much more prevalent. So a big challenge for the green movement is to change that perception, which is a combination of both marketing (the next topic) as well as changes in the way green is delivered. Simple changes (see my CSA “box of veggies” post, for example) can make a huge difference in perceptions.
  • Marketing – half of us at the salon were high tech marketers. Green technology is a classic high-tech marketing problem. We’re facing a “chasm” that we need to get across. There’s a technology adoption lifecycle in green building just as there is in new IT technologies. Of course, that’s one of the things that we here in Silicon Valley are pretty good at (we wrote the book on it :-). So one good set of steps to move forward will be to articulate a “Crossing the Chasm” kind of analysis of green, and figure out where our “beackheads” are, and how to get a “tornado” going.

Most of the news about green energy and climate change focuses on the big multi-million dollar technical projects, scientific breakthroughs, and “parts per million.” But as we discovered at our salon, there is a lot of “ground-level” work that has to be done at the same time – whether it’s to remove obstacles for builders to build green, or to help consumers understand they can save money and get better services and, oh by the way, save a lot of energy at the same time.

The Power Of Small Changes

Kale
We get a lot of kale in our CSA box of veggies (image by terren in Virginia, CC 2.0 license)

There’s a perception that green is more expensive and less convenient, and, truth to say, that’s sometimes true. It is more expensive to buy your groceries at Whole Foods. And putting solar panels on your roof doesn’t really save you money for many years, if at all, (although it’s still less than buying a new car).

But on the other hand, we know that there are lots of green things you can do that actually save money – replacing your incandescent lights with compact fluorescents is one familiar example. And if you’re building a house, putting in lots more insulation than is required by code can save a huge amount of both money and energy, while making your home more comfortable.

Sometimes it’s small changes that can flip this perception. I have a recent example from my own life that brought this home to me (so to speak):

Continue reading “The Power Of Small Changes”

Green Building Salon Update

Pepperoni Pizza
Pizza - a good reason to have a salon (callme_crochet, CC 2.0 licensed)

We had our first meeting of the new Green Building salon last night, at a local pizza place. Despite a few last minute cancellations, there were enough people there to generate some excellent energy. It was an impressive group, including:

  • An architect who has built several LEED-Silver and LEED-Gold buildings
  • An interior designer whose practice has always been about “green design”
  • One attendee spent several years in Washington in the 1970s working on energy issues with Congress, then got sucked into high-tech after that first green energy bubble burst when Reagan was elected
  • One attendee has been a brand manager for numerous large consumer packaged goods companies on the East Coast, and has now come out West for a new life focusing on green.

I’ll be posting more about the salon in coming days, including deeper dives on some of the attendees, and on what actions have and will come out of the meeting.

By the way, the next salon will be on February 10 in Sunnyvale. You can get more information and RSVP here. My friend Rich Wingerter has taken over the scheduling of these, using Meetup. I hope to see you there!

Avoiding The Cliff Ahead

Uluwatu Temple, Bali (HDR)
A cliff in Bali (image by seanmcgrath, CC 2.0 licensed)

My green building and blogging colleague Barry Katz just had a post about James Howard Kunstler on his The Future Is Green Blog. Kunstler is one of the “dystopians” featured in a  New Yorker article last week. Kunstler is not sanguine about what the future is going to look like for us and our descendants. He thinks that not only is global warming likely to cause a disaster, but so is the current, or an upcoming, financial meltdown. Barry writes:

In his view, anything short of ending our dependence on cars for personal transportation is a doomed enterprise.

In his blog ClusterF**k nation, Kunstler writes:

I’ve been skeptical of the “stimulus” as sketched out so far, aimed at refurbishing the infrastructure of Happy Motoring. To me, this is the epitome of a campaign to sustain the unsustainable — since car-dependency is absolutely the last thing we need to shore up and promote.

Could the terrible things he predicts happen? In the New Yorker interview he provides as an example and a warning the famous fall of the Roman Empire – the city of Rome itself went from a population of over one million in 100 AD to less than 50,000 in a little over 400 years. And there certainly have been many other similar collapses in history – even in pre-Columbian North America there were multiple population collapses due to resource overuse (and genocide, but that’s another topic).

The difference today – at least we hope – is that we have some Cassandras – Al Gore, Kunstler, the IPCC, me and Barry Katz, among many others – warning us, and we have the means and opportunity to take the warning. The question is, do we have the will to put the pedal to the metal to address the problems? For me, I see that as doing the following, and doing it much faster than anyone is actually predicting is possible today:

  • Immediately stop wasting energy – this means getting our houses and commercial buildings more efficient, both new and existing ones; getting more efficient cars on the road
  • Build out utility scale renewable energy as fast as humanly possible
  • Develop and commercialize technologies for distributed energy generation (e.g., photovoltaic roof panels and paint, mini-wind turbines, ground source heat pumps) and get them cheap enough to deploy everywhere
  • Develop and commercialize technologies for distributed energy storage – effective energy storage is one of the key sticking points for my vision of zero net energy homes and for accelerating the decline of traditional power plants
  • Figure out a way, or several ways, to get some of the CO2 back out of the atmosphere – reforestation is a start (and can make a significant difference, according to this study)
  • Finally, make structural changes to the rules and incentives of life so people will work closer to where they live, will be able to take public transit in a reasonable way, choose to build highly efficient homes not because its the right thing to do, but because it’s the law, or there are other concrete benefits, and so that businesses will find it’s profitable to save the world – whether it’s through being more efficient themselves, or by helping the rest of us “do the right thing”

I call this blog “Keeping The Lights On” because I am optimistic that we’ll figure out how to have a decent life without CO2, that we’ll figure out how to keep the oceans from rising too much and losing too many species, and that civilization won’t collapse due to a financial crisis in the meantime. There are a lot of hurdles to be leapt to accomplish this, and many of them will be costly – but that means that someone’s going to make some money on them, so there will be incentives. And that’s the other half of the title – “Profitable Applications” – business can drive this transition, for profit. The big challenge is getting business ramped up fast enough to save our butts – I think it can happen, and even with the economy in its current sad state, we’re still seeing hopeful signs.

Well, that’s a couple of pages full of assertion and conjecture – I’d love to hear your thinking on this.

Zero Net Energy Homes Part 5 – Passive Houses

The Smith House - A passive house in Urbana, IL
The Smith House - A passive house in Urbana, IL

What if you didn’t have to heat your house at all, no matter the climate? Or at least, never turn on the furnace? Well, that’s practically what life is like in one of the “passive houses” designed with the principles of the PassivHaus Institut in Darmstadt, Germany. Recently featured in an article in The New York Times, No Furnaces but Heat Aplenty in ‘Passive Houses’

… these houses are part of a revolution in building design: There are no drafts, no cold tile floors, no snuggling under blankets until the furnace kicks in. There is, in fact, no furnace.

The idea of keeping all the heat inside a house and all the cold outside has been around for decades, but it took a number of technological innovations to do so while preventing stagnant air and mold. Passive houses are characterized by extreme levels of insulation (R-40 or more) and extremely air-tight construction to prevent drafts and heat leakage, coupled with sophisticated mechanicals – called air-to-air heat exchangers or heat recovery ventilators (HRVs) – that constantly refresh the inside air with outside air, while making sure the heat stays in.

Because they use 80% less energy for heating and cooling, passive houses are going to be a critical part of the goal of zero net energy homes. The less energy that’s needed to operate the house – and heating and cooling typically is 40% or more of the energy use in a house – the less energy has to be generated with solar panels or a wind turbine, lowering the cost of energy generation and improving the payback period.

And the cost of building a passive house, at least in Germany, is typically only a few percent higher than building a regular house of the same size, and the energy payback and the savings versus installling a traditional central system – not to mention the improved indoor air quality – makes the payback quite fast.

Over 6,000 passive houses have been built in Germany, but their take off has been slower here in the States. There are about a dozen “official” passive houses – sanctioned by the Passive House Institute US, the U.S. arm of the PassivHaus Institut –  in the U.S., although there are a number of unofficial ones as well, including quite a few mentioned on their forums.

The take off in the US has been slower for a variety of reasons – the different climates across the country, the fact that the expertise is primarily in Germany, and that much of the mechanicals – like the HRVs – need to be imported from Germany.

I bet you’ll be seeing passive houses going up on your street any day now, as the concepts are propagated into practice. The PassivHaus Institut website even features a section on renovating existing houses to passive house standards.

Green Building/Green Energy Salon in Menlo Park on Thursday

Green energy/green building salon – first meeting is this Thursday night (1/29) in Menlo Park.

My Soul
Green things (image by WTL photos, CC 2.0 license)

I’m starting a green energy/green building salon, and the first meeting is this Thursday night (1/29) in Menlo Park. Sign up on this invite/RSVP page to let me know if you’re coming.

If you’re interested in green buildings like me, or are working out how to have a new career in the green economy, you should drop by!

As I’ve mentioned, I have a modest little goal to ensure that all 50,000 housing starts in California in the year 2018 are “zero net energy.” That means they’ll generate as much or more energy as they consume in operation.

Do you have a green energy or green building goal? Do you want to talk about it? Do you want to help me achieve my goal? Maybe we can help each other.

Right now is the time to kick start the green economy. There’s a lot of intellectual capital here in Silicon Valley, a lot of us are committed to seeing the world pull out of our energy nosedive, and working together we’ll accomplish more than working by ourselves.

This salon will be an opportunity to share, to learn, and to meet others with complementary goals. I hope you can attend!

The location is:

1225 El Camino Real
Menlo Park, California 94025 Get Directions

Obama’s Commitment To Green Buildings

baggerloch
A hole in the ground waiting to become a building (image by extranoise, CC 2.0 licensed)

Obama has a lot of plans, as shown on whitehouse.gov, his public website. But one of his points, on the Urban Policy page, is the following:

Use Innovative Measures to Dramatically Improve Efficiency of Buildings: Buildings account for nearly 40 percent of carbon emissions in the United States today and carbon emissions from buildings are expected to grow faster than emissions from other major parts of our economy. It is expected that 15 million new buildings will be constructed between today and 2015. President Obama and Vice President Biden will work with cities so that we make our new and existing buildings more efficient consumers of electricity.

It’s interesting that one of the most significant parts of his energy plans (buildings use 40% of the energy in the U.S., so this could have a giant affect on our country’s energy use) is in this Urban Policy section. I assume this is because of the “green jobs” aspect of building green. Tradespeople jobs are a great way out of poverty, and we’re going to need a lot of new tradespeople, with new skills, to transform the housing and commercial building stock to be highly efficient.

Green Shopping For DIYers

Main Street #6 (Superior Appliances)
Are They Energy Star Certified? (Image by kevindooley, CC 2.0 licensed)

In the national consciousness “green is the new black.” But what if you want to do a little work around the house – paint the kitchen, retrofit with some compact fluorescent lights, build some shelves? How much of a challenge is getting materials and advice for a green DIY or remodeling project? My friend Rich Wingerter decided to find out a few weeks ago, and went on a little shopping trip. He recounts his experience with Green Shopping on his blog The Greens.

“My take is that many green products are within hailing distance of their traditional (let’s say “polluting” cousins). If you can do a remodel with green materials and spend no more than, say, 5% above what you would have spent anyway, then you will probably profit from the results. Are there enough green options comparable in price to reasonably do a green remodel in the Silicon Valley area? To find out, I went shopping. I wanted to find out what kinds of green building materials I could buy and not blow my (theoretical) budget. “

Some highlights:

At Orchard Supply Hardware (a California chain) he asked about sustainable lumber:

I was told that they don’t sell this kind of lumber, and that they didn’t know anything about it. They directed me to the commercial desk, on the theory that maybe they had something for contractors.

At Orchard’s commercial desk he asked about green materials in general:

(Explaining, of course, that I was talking about eco-friendly products, not objects painted green). Blank stare. Crickets.

Rich fared better at Kelly Moore Paints and Lowe’s. Did Kelly-Moore have green products?

Yes, they did, and they didn’t go blank when I asked. … They had an option with a zero-VOC, as well, and gave me pricing so I could compare with the default versions. In addition, they carried Yolo Colorhouse® paints, which are zero-VOC base.

How about Lowe’s?

Joe Roche, a Regional Commercial Sales manager, understood what I was looking for. Joe was good enough to walk through part of the store with me. We went to the lumber section and looked for certified lumber. We didn’t immediately spot any, but Joe said that they often have it even if it’s not marked. He said that they had done a LEED-certified project, and they had to special order the lumber so that it all came stamped.

Rich went on to find some low-e windows and a number of Energy Star appliances at Lowes. In his post he also compares the prices of traditional and green materials, such as the paint at Kelly Moore and some of the Energy Star vs. non-Energy Star appliances.

Rich’s conclusion is:

While companies are trying to market green building materials, and in many cases probably have them in stock, the word hasn’t really filtered down to the sales floor.

Rich’s focus on this blog and on his site Green Making is green building in the San Francisco Bay Area. He is building not only an information base, but also a community site for builders and buyers who want to build green. It’s a great resource for everyone interested in green building and zero net energy homes, especially those of us in the Bay Area. I recommend taking a surf through and putting it on your bookmarks.

Have you had a “green shopping” experience? Have you been able to get good advice on a green DIY project from a local or chain hardware or building supply store? How about bad advice? Please share your stories in the comments – we’d love to hear them!

Zero Net Energy Homes Part 3 – The Federal R&D Agenda

A House
House, ready to become zero net energy (Image by Panoramas, CC 2.0 licensed)

In October 2008, a number of federal government departments and research organizations collaborated to produce the Federal R&D Agenda for Net Zero Energy High Performance Green Buildings (PDF). It’s a fascinating document, its origins driven primarily in response to two energy policy laws passed in 2005 and 2007 (during the Bush administration). In particular, the Energy Independence and Security Act of 2007 (EISA 2007) created an Office of Commercial High Performance Green Buildings and a consortium on a Zero Net Energy Commercial Buildings Initiative. This consortium produced the R&D agenda.

The EISA 2007 act also includes a $250 million program that the DOE and other agencies are administering with the goal of “all new commercial buildings to be so efficient in energy consumption and in on-site renewable energy generation that they offset any energy use from the grid,” part of the Energy Independence & Security Act (EISA) of 2007 passed by Congress and signed by President Bush last year.

Noting that buildings represent about 40% of U.S. energy use, and 40% of our greenhouse gas emissions, the report says:

Buildings present one of the best opportunities to economically reduce energy consumption and limit greenhouse gases.

And we already have in hand technology and techniques to get a good start on this:

From an energy perspective along, high performance building technologies can already reduce building net energy consumption on average by 30-50%. New technologies to achieve net-zero energy – buildings that over a period of time produce as much energy as they consume – must be developed and integrated holistically into building design to make buildings more self-sufficient.

For the remaining 50% of the job, the report defines six areas of research and development that are needed:

  • Improving our ability to measure the performance of buildings, and design integration

    Credible performance measures, combined with tools, performance data, and design guidelines, will create market demand for emerging building energy technologies, economies of scale, and reduced capital costs.Designing for effective daylighting, ventilation, and passive solar energy management, for example, could yield energy savings approaching 40%, without advances in individual technology efficiencies.

  • Developing building technologies and strategies to achieve net-zero energy

    Energy-efficient and direct-use renewable energy technologies – in the forms of cost-effective materials, components, subsystems, and construction techniques – still have enormous potential for energy savings at costs lower than acquiring supplies from traditional or renewable power sources. At the same time, renewable power and other supply technologies also have enormous advancement potential.

  • Improving water use and water retention
  • Improving the energy footprint of building materials and building activities
  • Improve occupant health, safety, and productivity
  • Enable these new technologies to be put into use in practice

    Adequate information and communication flows are critical to achieving energy and resource goals. Substantial technology transfer efforts will be required to penetrate all facets of the building and construction sectors.To enable a future where truly integrated design is the rule, rather than the exception, the process by which buildings are planned, designed, constructed, operated, and demolished requires a radical cultural change.

I recommend taking a look at this report – it’s quite interesting reading. As a government-sponsored work, it is naturally somewhat conservative, but even so it holds out a lot of hope – and suggests numerous avenues to pursue – for significantly reducing the energy demand of our commercial and residential buildings in the U.S.