How Passive House Makes Net Zero Energy Homes A Reality

Learn more about Passive House on RM-PH.com

If you have lived off-the-grid for awhile like I have, you may also find the newly found interest in net zero building a bit amusing. Most of those who tout NZE do so from the luxury of a grid safety net, and those who want to go "off-grid" are typically more motivated, I think, for a spiritual or political purpose than the technical or environmental challenge. They never actually move to the cabin in the mountains or the yurt in the plains, or take the experience to fullest and design a stand alone system. But now the next thing is being served up in the form of Net Zero Energy living, a rather Zen-like approach to a built environment where one takes nothing out and ask for nothing in return.

The exciting thing is that technically speaking NZE is actually not too hard. What you need is a really, really big roof. The average home consumes just shy of 40 kWhs of electricity a day which very roughly equates to a 10kW solar system. At 10 watts a square foot you have a 1000 square feet of glass and silicon on the roof should be enough for an average house. Yikes(!) basically a very big shed roof covered in $50,000 or so dollars to make NZE a reality. I think I am probably low balling these numbers but they give the picture. Builders got smart and started lowering their home energy use as well to make NZE a reality, but let's face it, a really good home now is considered 30% better than code, and we really haven't talked about all the crap plugged in. So now the trend of NZE homes is looking at a upgraded house shell still with a big ol' honken solar array. The market message is if you want NZE it's going to cost you. Most folks are like me who could not afford anything near that, so I put up a tiny array and worked really hard at making sure I did not need the energy in the first place. Actually it wasn't hard to use 1/10th the average energy.

In the past year I have been wokring with group developing Rocky Mountain Passive House and while it took me a while to get to Passive House here I wanted to make the point that it's not about making energy that really counts for net zero energy consumption, it's about not needing it in the first place. That is what passive is all about. We cut 90% of all energy out of the equation which means that the building needs a much, much (much) smaller PV array. The size depends on how much energy the occupant uses to be fair, but we aim to give the project a real head start to NZE.

The dollar equation is even better. While a Passive House costs more than an average house to build for now, a NZE Passive House cost less than a comparable NZE project, and you get your upgrades for free (like some cheesy sales pitch). Think of it as opportunity savings: getting incredible windows and doors and a state-of-the-art envelope which equals comfort and craftsmanship for less money than plucking it down for a stack of PV on a roof, which frankly is not really a lifestyle enhancement. Get rid of the HVAC equipment costs and up-keep and the savings are durable and long term. While your spiritual or philosophical needs for low impact housing is met - http://rm-ph.com/about-the-passive-house-standard/comfort/ your actual comfortand budget is taken care as well. With Passive House your roof's solar collection potential is now available to feed things like an electric car you buy in a couple years, which makes your overall energy and environmental impact dramatically improved as well as future proofing your energy needs. Passive House makes the potential of a good energy citizen a reality, reducing the demand to a trickle and providing a genuine potential for eliminating dirty energy from your life both technically feasible and long term affordable.

Net Zero Energy (or if you prefer Zero Energy Building) can be measured in a handful of ways depending on what you include: embodied energy, equipment life span, line loss from energy supply, simple net-meter measuring. For instance if your meter says '0′ net energy consumption for the year this will not account for line loss or inefficiencies at the energy source like the coal plant, so the devil of what is reality is in the details. Producing energy onsite is not a panacea either, it typically is overused when system thinking is not applied and a market driven by products takes over. Don't get me wrong, I love photovoltaic technology because it is solid state, will last longer than your roof and is utterly dependable. I have been off-grid for 16 years and no, it is not NZE as I use wood for heat and propane for hot water and cooking. For that you really need to be a good citizen and feed the grid (just without the extra mortgage).

The Utterly Amazing Colorado Renewable Energy Conference

Hope I'm not over selling this but I have been part of a team putting together what may be the best looking conference I have seen. You can read the bulletin below but when I was asked to put together a LEED professional track I thought of the most interesting folks in the state to consider participating.

They all said yes to my amazement- so we will have an all star cast of sustainable builders providing an inside scoop from Award winning Architect H:T Design, the glamorous David Johnston and his Zero Energy Home musings, the ever cool Brian Dunbar of CSU's IBE. We'll cover the pioneering LEED for schools projects, learn about a radical energy design called Solar Banking and hear about the real world of planting green roofs in Colorado.

The second day I have assembled three ground breaking building tech companies, all featured on Inhabitat.com, a Passive House seminar, and some serious energy efficiency for your existing home with everybody's favorite Paul Kriescher of Lightly Treading. Hot Damn, I should print tee shirts.

And now the blub-- Attend the Colorado Renewable Energy Conference (CREC), themed “Local Action—Global Solutions,” in Fort Collins June 2-4, 2011.

Hosted by the Colorado Renewable Energy Society (CRES), the conference offers an in-depth exploration of the extraordinary work done in Colorado and Northern Front Range. Over 50 sessions and 70 speakers on renewable energy, sustainable building and technologies, environmental science, and more will be presented by foremost experts from throughout Colorado and across the nation.

Discover how Colorado is a world leader in the new green economy with an entire Thursday dedicated to professional development with credentialing tracks, including LEED-accredited professionals, real estate “EcoBrokers,” engineers, educators, and community-based energy development.

On Friday, explore public policy and governmental initiatives in comprehensive sessions with experts from NREL, CSU, and industry-leading companies. Also on tap is a tour of some favorite green sites and tastes of Fort Collins. Celebrate local and state renewable-energy innovators as well as CRES’ 15-year anniversary at the awards banquet.

Bring the family on Saturday for a day full of hands-on fun and how-to help for green building, solar energy, electric transportation, local action, green companies, and much more.

CRES gratefully acknowledges the leadership role of the City of Fort Collins in helping host CREC.

Get the details and find out how to participate right here on the conference Web site

A Solar Eclipse in Colorado

Xcel Energy, the largest provider of electricity in Colorado has been at the center of a solar renaissance largly through no fault of their own. If you get Xcel electricity then you were able to get a deep discount on a solar electric system that would be the envy of your non Xcel customer friends at almost half of the sticker price, until last week at least. Xcel has decided to unceremoniously pull the plug on the Solar*Rewards rebate program to the surprise of hundreds of solar companies that grew from the rebate frenzy.

I have not been the biggest fan of this system as I have always contended that efficiency is above all the soundest investment that has the added bonus of comfort and health. Alas the consumer has spoken and they want solar panels at good prices. Along comes the first voter approved amendment in the country for renewable energy, and part of Amendment 37 is a distributed energy resource as a percentage of the total renewable profile, subsidized by rate paying customers of publicly traded companies under the direction of the Public Utilities Commission. Whew.

The result is cheap solar for those who can afford it which is subsidized by all rate payers. This actually is a good thing, public policy approved by voters to tax themselves to provide renewable energy for themselves (if they happen to live in a for profit service provider area) is a very forward thinking step. The result is huge demand and a flourishing and competitive market of solar providers. The solar trade group CoSIEA has hundreds of members which have seen a real demand for solar energy with growth nearly doubling in the last year. If you don’t like subsidies I would suggest you protest your gasoline supplier as your bear your outrageousness on the small companies that we are speaking of. This is a bold step in developing a viable clean energy future that we all ultimately will benefit from.

That growth has been in large part due to the financial stability of a rebate program mixed with reduced equipment costs, a competitive landscape and strong demand. This four legged chair just had a leg cut off by Xcel Energy and previously by Black Hills Energy. Xcel’s news release claims that the price of solar equipment is now competitive, and with the government subsidizing solar and Xcel fulfilling their obligation of Amendment 37 they are happy to abandon this program because of its success at creating a marketplace.

Now as I mentioned I am not a big fan of subsidizing solar energy without a comprehensive energy efficiency effort. Nor do I like seeing solar electric get moving while solar thermal stands at the side of the track waving goodbye, but the train has long left the station. With the sudden drop in support the train very well may be going off the cliff. When Black Hills dropped their rebate program installs almost disappeared. CoSIEA is estimating about half of the 5300 jobs in solar will be lost in short order. We just lost another leg of our proverbial chair (sorry about the mixed metaphors by the way.)

"We look forward to the industry's continued progress so that it can ultimately become self-supporting," Xcel Colorado president David Eves said in a statement.This was a believable notion as Xcel had a schedule of slowly stepping down their rebates in an orderly and timely manner with the consensus of solar companies. By cutting off the rebate program immediately and stripping all credits to the bone Xcel (and Mr. Eves?) is really saying to me “We are tired of dealing with you pesky small solar companies and distributed energy is such pain so we’ll try to run you out of business even though it really cost us very little.”

This is the only reasonable conclusion I can have at Xcel’s behavior after their touting of themselves as such a green corporation. They are well aware of the instability it will cause for solar companies who have tight margins and high overhead. Most planned projects will have to be put on hold and renegotiated, many of them undoubtedly being cancelled. The market is also very young and has not given the industry much time to ramp up supply with demand. Xcel says they have met their requirements and is proud of the work they did but I am not so sure they are not meeting the expectations of the electorate (and their customers) who clearly wants a thriving renewable energy marketplace. A two legged chair is not what the public wants.

So that is the background. Will the industry fall apart like it did in the eighties? Will Xcel back off like they did when they made other unpopular decisions that quickly drew the wrath of consumers (like a surcharge for solar owners) or will the PUC come in to settle things down? One thing is for sure, Xcel will not be burdened with the reputation of being a “green” utility.

Green Building Interview on Saudi Arabia

Here is part of an interview I gave for the International Quality & Productivity Center. They are hosting a green building conference in Saudi Arabia in March focusing on how to do it affordably. If you want to read the rest you can access it here.

IQPC: Is there a concerted effort in Middle Eastern and other major governments to inculcate knowledge about renewable energy and sustainable construction from the grass‐roots level by starting to educate the younger generation about this necessary sector? Do you see any hindrances on this front?

AM: Most governments at this point are spotty in their assertion for renewable energy and sustainable building as complex sociological and financial issues cloud a concise message to their younger populations. None‐the‐less sustainable technologies and construction are the fastest growing sectors in many colleges and demand is forcing institutional and leadership responses. As young Middle Eastern designers and builders see the immense renewable energy resources of solar for instance they will demand access to the technologies and jobs which entail its implementation. When we speak about sustainability we are really talking about a massive generational shift. The implementation of education on sustainable infrastructure will need to engage the entire cross section of a young population regardless of race, class or gender to be effective.

IQPC: How do you see sustainable construction having a positive effect on the Middle East’s emerging economies?

AM: Sustainable development and construction is being embraced for a multitude of reasons: health, energy & water security and quality. For a company whose greatest costs are payroll, for instance, a building that has great IEQ (indoor environmental quality) will immediately see an increase in employee productivity, with a resulting edge in the marketplace. For a desert region, water and peak energy load are major long term issues that sustainable building addresses in a substantial way. The standard of living for a growing population will be based in large part on how they allocate their resources. They can create buildings that actually provide resources for a community rather than take from it. A concerted effort in sustainable development can result in an entire region creating an economic super‐cluster based on its investment.

IQPC: Sustainable construction cannot have the desired effect on an economy’s stability unless it is accompanied by concerted efforts to also implement renewable energy alternatives. Would you agree with this statement? Is this becoming a reality on the ground?

AM: Renewable energy production technologies can often be centralized or distributed, but by their nature buildings and developments are only distributed, meaning that efficiency gains can be only provided at the source. A flattened peak energy demand presented by sustainable building is utterly necessary to implement broad use of renewables. Energy efficiency is the lowest cost of all infrastructures in simple payback when first built but become increasingly difficult to achieve with existing buildings. As more renewable energy sources come online they will need an adequate infrastructure capable of properly using the energy when produced. While much attention has been paid to renewable energy it is only viable when the overall consumption of fossil‐fuel based energy is reduced and infrastructure can properly use it. Wind energy for instance has already saturated certain markets which then have to sell the energy at a loss or shut the turbines down, so a balance of supply and demand is critical for economic stability.

This interview was conducted for the Cost‐Effective Sustainable Design & Construction Saudi Arabia 2011 conference which takes place from 13 ‐ 16 March, 2011 at the Riyadh Marriott Hotel, Riyadh, Kingdom of Saudi Arabia. For more information on the event or to register, and to download more exclusive content, visit www.sustainableconstructionsaudi.com or email us on enquiry@iqpc.ae

eVolo Magazine Cities of Tomorrow

eVolo Magazine is an exploration of the leading edge of building design. I was fortunate to contribute two articles to the third edition titled CITIES OF TOMORROW Envisioning the Future of Urban Habitat, available now.

BEIJING CREATIVE ZONE: At its heart, the UNStudio’s winning design for the Beijing River Creative Zone competition is a place of evolution. Designed as an urban interface with the natural environment, the complex will house and incubate creative business ventures that, interacting with each other, form a creative economic enterprise cluster. From the urban grid it may be an interpretation of the adjoining undulating waterway, or conversely from the perspective of the river, the segmented design scheme may be seen as breaking the vast Beijing urban grid.

MILLENNIUM PARK AND THE FUTURE OF GREEN URBANISM Interview with Helen Doria: People are much more attracted to a project that is extraordinary than something that plays it safe. Who wants to give their money to a nice safe ordinary project? What excites communities? Certainly not a cookie cutter project. The vision and the vision carriers are the ones who make cities spectacular. Those vision carriers can be everyone from the architect and designers, the Mayor, to the funders and the people of the city. Everyone can hold a vision.

You will find the rest of these two articles and much more in the magazine, not on the internets. Why is it worth it you say? Thought provoking, beautiful, ugly, something to keep. Or as eVolo says -- to study, to develop, to evolve, to fly away...

Passive House: A Case for Less Tech in Building

What’s better than high tech? In a word (well two) no tech. This is the elemental argument for Passive House. I attended a very informative talk by Kat Kligenburg the Executive Director of the Passive House Institute US. The logics and economics of Passive House has been well developed and documented in Europe and now the case is being made for a US market.

Build a shell so well insulated and air tight that cooling and heating is seriously reduced, which in turn means the home does not require an active HVAC system. A building is developed using an elaborate energy modeling program that accounts for wall details, windows, doors, internal heat loads (like you are), external climate conditions, orientation, thermal mass properties, air exchange, and on and on. The end result is a home that eliminates the cost of HVAC.

So what does this mean in real terms when it comes to the decision making process of building? If you are aiming for cheap plentiful square footage then this is not for you. If you have that log cabin house in the woods with a great wall of windows in your mind then you are pushing your luck. If you are looking to build the most sustainable home that has an outstanding energy profile, and your are willing to give up a dormer or two you might have just hit the jack pot.

Right now America’s notion of “green” building is basically conventional building with a whole lot of gadgets hooked up to it. Maybe we’ll put in a 2x6 wall instead of a 2x4 and bump up the windows but the real strategy is almost always to pluck from the budget for high tech. Do a search for green building and you will be inundated with high tech stuff—condensing furnaces, solar thermal, boilers, radiant floors, SEER ratings, solar panels, geo thermal. All great solutions to keep an OK house comfortable.

The Passive House argument is that if you properly design and implement a super insulated envelope you eliminate the need for all this gadget wizardry. It really starts to make economic sense when you don’t need really expensive stuff like a ground source heat pump (aka the mislabeled geo thermal system) to make the house work. The project parameters change and frontend design work becomes critical, rather than plugging in equipment to a preconceive design.

Now extrapolate this thinking into the not so distant future. Your gee-wiz equipment is still using energy, aka costing you money and requiring maintenance. Counterpoint the Passive House model in which there is no required continuing operating cost, meaning lot less problems compared to the gee-wiz stuff buried in the mechanical room. I have seen a few really complex systems that will eventually develop expensive ticks. So dollar for dollar the Passive House makes a better economic and environmental choice. Well at least that is what Ms. Klingenburg will have you believe.

Ground source heat pump hydronic cooling and heating with solar assist:

A field of solar

As a part of our 2010 Solar Tour in Ft Collins we got a inside look at the huge solar farm on CSU's Foothills campus. Here is an artful look at the 2MW array.

Workshop: The Art of Sustainable Building: Seeing the Connections

I'll be co-presenting a workshop with my friend Scott Peters on the latest thinking on green building. We are not doing a PowerPoint, only a few props and spontaneous conversation on everything and anything to do with sustainable building practices.

4pm in the green building tent-- Saturday, September 18th at the largest green fair of its kind, The Sustainable Living Fair.

Here is our description: Beyond branding, green building is real building science.This lively and participatory presentation will cover how reducing energy consumption and the benefits of renewable energy are interdependent. Learn the connection between what we build, "the third skin" and "the long tail pipe" and what to do about it. Please bring your questions.

Andrew Michler and Scott Peters are both LEED APs and NCRES Board Members. They share a passion to educate, encourage and engage in the greatest challenge of our time, creating a sustainable built environment. Andrew is a consultant and writer, Scott is a builder and trained Home Energy Auditor.