Category Archives: passive solar

Net Energy Positive Passive House

The Passive House in the Woods in Hudson Wisconsin officially clocked a net-energy positive meter reading in 2011.

What does that mean?

In short, it made more energy than it consumed. While we predicted this with our energy models, we found and learned through monitoring that some equipment and appliances use more energy than assumed. On the flip side, user behavior plays a major role as well and can effectively lower energy consumption over the predicted model. (Source)

Solar Powered Art – Craig Colorusso

A solar-powered art exhibit? It wouldn’t be the first time we’ve covered something of that sort on the vaunted pages of mnp, but it could be the coolest.

Creating the effect of an enchanted forest of singing trees, Craig Colorusso’s “Sun Boxes” installation can be walked through in a leisurely manner, or run through at full speed in a last ditch and extremely risky move to avoid the approaching enemy.

Sun Boxes is a solar powered sound installation. It’s comprised of twenty speakers operating independently, each powered by the sun via solar panels. Inside each Sun Box is a PC board that has a recorded guitar note loaded and programmed to play continuously in a loop. These guitar notes collectively make a Bb chord. Because the loops are different in length, once the piece begins they continually overlap and the piece slowly evolves over time.

Basically, I imagine this to be one harmonious but constantly changing, amplifying, and diminishing barrage of sound that keeps on rocking (God forbid it’s cloudy out). Although not billed as such, I find this to be a potentially very interesting and mesmerizing marriage of sound and mathematics. Plus, this ninja is from Beantown!

Craig will be at the IMA from March 18-20, for what we hope are 3 beautiful days. We recommend you wander amongst the enchanted sound-forest, put don’t pick the flowers!

We are all reliant on the sun. It is refreshing to be reminded of this. Our lives have filledup with technology. But we still need the sun and so does Sun Boxes. Karlheinze Stockhausen once said “using Short-wave radios in pieces was like improvising with the world.” Similarly, Sun Boxes is collaborating with the planet and its relation to the sun.

More Info Here

Building A Straw Bale House: The Journey Begins


It is official: my dad started his journey from NC to NM this morning to begin construction on the straw bale house. He set off for the 3-4 day drive in our ancient-if-not-so-fuel-efficient ’92 Volvo 240 full of belongings and our two dogs. My poor mom is going to be lonely for the next few months (though she will probably miss the dogs the most…). So be on the lookout for updates on the construction progress over the next few weeks and months. And check the straw bale archive to learn about his designs and software.

Straw Bale House: In Anticipation of Construction


There has not been a lot of anticipation growing this winter from friends, family and ninjas alike for the groundbreaking of the straw bale house. My dad has started receiving construction drawings and will be breaking ground officially in April. He is going to build the garage, which is not going to be made with a straw bale frame, first thing so that he can live in it while he builds the main house. More news to come on the dates for stacking the straw bale frame. While I was at my sister’s in Albuquerque for Christmas we took a trip out to the site and I got a few photos.


In the meantime, I have been meaning to post some valuable advice on building your own home from seasoned MNP friend Jennifer over at Offbeat Homes. Jennifer actually built her own eco home in the East Mountains of New Mexico, not far from the site of my parent’s house. She had a bit of a love/hate experience with building her home, and thus, compiled two lists: 10 Reasons Why Building Your Own Home Sucks and 10 Reasons Why Building Your Own Home Rocks (in that order). Here are the abbreviated lists, but please do go check her out. I’m going to go with the good list first, to keep things optimistic:

10 Reasons Why Building Your Own Home Rocks

1. You feel extremely strong: Home building pushes you to the limits of what you can accomplish in a purely physical sense.
2. You will learn from doing: I was always into design and building but you can read about building techniques all year long; it’s only when you actually have to put the techniques into action that you get a real feel for what can and should be accomplished in building practices.
3. You get to create something from scratch: This applies even more if you design and build.
4. What you learn from mistakes is invaluable: Number 3 (above) brings up the decisions you make. Some of these decisions may be crazy stupid but the good part is you will never, ever make the same mistakes twice.
5. You gain handy lifelong skills: I could barely hammer a nail when we started the house. Now you would not believe the things I can fix, the tools I can use, and the things I know about home building.
6. You can impress people: I’ve had people tell me that they loved aspects of the house which is cool but the best person I impressed was my son Cedar.
7. House building is great for kids: Obviously if you don’t have kids you won’t care. If you do have kids they will love the whole process. Cedar spent long days at the house site. We let him nail boards, carry items, paint, and clear land. He always wanted to help.
8. You can save and make money: This really depends. On the positive side we got our land super cheap, did most of the work ourselves or bartered for help, built in a choice area, and were able to choose cost effective materials. The negatives were that we went WAY over our original time line and failed to plan which ran costs up again.
9. You can make an eco-difference: You can renovate green or build green.
10. It’s fun: It took me a bit to think of a number 10. Sometimes it is fun. you can take a group of friends out and chat while you paint or go have a sleep over in the unfinished rooms. Depending on where you build you can see and enjoy wildlife like deer, birds, and snakes. (NOT spiders).

10 Reasons Why Building Your Own Home Sucks

1. SPIDERS! Big ones, little ones, and all of them wicked scary. Not to mention we built up on a mountain in New Mexico so you just know there were tarantulas around. In fact, a friend of mine who lived on a plot of land down the road caught one. Shiver.
2. It’s the slowest process known to man. Does it have to be? Why, no and maybe someday I’ll tell you how to cut building time. But in this case it’s just going to stand alone as a negative.
3. Clearing and leveling: What you may not know if you’ve never built a house is that you have to move all the trees (obviously) but you also have to make sure your land is flat and free of rocks for the foundation. We had no idea going in that rocks the size of boulders hidden in the earth would be such a problem.
4. Hidden costs: There are maybe 618 hidden costs when you build your own house. Is that number accurate? I can’t say for sure but it does feel like I estimated a little low.
5. Unorganized people don’t know what they’re doing when. If you aren’t organized please, please hire someone who is to do all the planning for your house. We constantly fell behind schedule because something was forgotten or not taken care of when it should have been.
6. No bathroom: I do not want to pee outside with the scary spiders.
7. Your hands go to hell: You can wear gloves. In fact I hear that’s a popular choice among home builders. But I don’t like them. I always felt like I wasn’t sure where my hand was exactly and it feels slippery.
8. Child labor: It’s against the law and sad to see! Just kidding.
9. Weather extremes: It’s New Mexico. There’s no a gentle spring or a crisp fall. There are basically three weather patterns in Edgewood, NM. Boiling hot, freezing cold, or windy enough to blow a car away. The wind will occur in both hot or cold weather.
10. You can almost go blind: On the roof! Remember the afore mentioned wind that will blow a car away. We were on a deadline and decided that even though we were having heavy winds we’d go ahead and get the roof papered. In retrospect; bad, bad idea…In the late afternoon our work came to a screeching halt when a huge gust of wind blows sand completely under my goggles (great safety goggles) and into my eyes.



Jacques Ferrier : Hypergreen


The Hypergreen tower, designed by Jacques Ferrier for a competition in Paris, is a 250 meter / 60 storey tall mixed-use ‘green’ building [hence 'hypergreen']. The building’s structure emerges as an intricate concrete lattice system, wrapping the facade in the woven pattern and allowing for the floorplates to be nearly column free. This structural system also creates an interesting intermediate space between the building’s glazing, where Ferrier has apparently planned for some exterior gardens / greenery.


What makes the Hypergreen tower green, you ask [other than the name]? How about its:

  • geothermal heat pumps
  • photovoltaic panels
  • integrated wind turbines [seen at the top of the building]
  • earth cooling tubes
  • vegetated sky lobbies
  • a roof garden
  • rainwater recovery system

…and the aforementioned flexible / adaptable column-free floor plates.



::images from Jacques Ferrier Architecte, project via Jetson Green::

::listen to the podcast::

Building A Straw Bale House: Clearing the Site


I have a progress update from the field of my dad’s straw bale house. He visited my sister and her family in New Mexico in mid November and started clearing the land at the site. If you are new to the green.mnp Building A Straw Bale House series, check out the first entry to read about the design and software my dad has developed for his and my mom’s dream green retirement home.

Here is what he had to say:

I recently took a six day trip to Albuquerque. My agenda was to clear the site and check in with my builder, Cadmon Whitty, and Anissa Hogeland, the architect who is turning my conceptual design into construction drawings.

I stayed with my daughter and son-in-law and got a chance to catch up with them and my grandson, Joshua, 4, and see my new granddaughter, Skyler, 8 months!

When Anissa first laid out the house on a topo drawing of the site (a little $1400 survey cost) she suggested that floor joists over a crawl space might be cheaper than a slab on grade, due to the slope of the site and the amount of fill we would need to bring in for the slab. I was reluctant at first about losing the thermal mass in the slab, but I talked it over with Cadmon and he said that a two inch layer of lightweight concrete over the wooden subfloor works well for holding the radiant heating tubing. He did a top-of-the-head cost estimate that indicated this approach would be a bit cheaper than the slab and fill. When I ran this new approach through my energy model I was surprised to find that it didn’t increase the heading and cooling swings appreciably. This is because there is still a lot of thermal mass in the interior walls – cinder block with every other cavity filled with cement or earth. Once you have “enough” thermal mass, adding more has progressively less effect. I’m now glad about the crawl space, as it will make plumbing and other systems much more accessible. This is an environmental improvement too – less cement with its embedded CO2 emissions.

Clearing the site began with renting a chainsaw and chipper, and deciding just where the house will sit on the site. After marking out a few rough corner locations I began cutting away. It’s sad to cut down healthy trees, but there’s no way around it within the house footprint.

After the first day at the site I came home with a terrible stiff neck and shoulders. I guess that was from a day of chainsawing after not doing any for several months. Maybe stress or sleeping wrong had a part in it too. It stayed with me for the whole trip. Nights were the worst – just turning over in bed was a slow, painful process. One of the unexpected joys of building a house at age 66.

With breaks for lunch and some minor troubles with the chipper it took two days of chainsawing and two days of chipping. At the end I ran out of time and gas in the chipper with just a small part of the last brush pile left. There are now several stacks of firewood and two piles of chips which will provide some landscaping mulch. From my Coast Guard days I’ve named the piles after two small conical islands outside the entrance to the harbor at Saint John’s, Newfoundland, which are affectionately know by sailors as Mae West.

There will be more clearing at the south edge of the lot, but already the view is quite something. There is a broad valley of rolling hills, fields and forest, with several mountain ranges receding into the distance. I’m so glad I reoriented the house design to make the most of the view!

Another high point was the hospitality shown by the neighbor on one side, who helped me considerably with the chipping. His help and tool box saved my bacon when the chipper jammed one time. I also met the neighbors on the other side – a nice young couple who I’m looking forward to knowing better.

I also talked with a couple of mortgage brokers about construction financing. There will be applications and financials to fill out for that. I’d like to be the general contractor for the job, as that could save some money. But I also know that all the scheduling and phone calls to subs are not my strangth – I’m a poor manager. “General contractor” involves several kinds of insurance, several kinds of risks, and the managing of the subs and the scheduling of the construction process. I’m hoping to work out an allocation of the different elements between Cadmon and myself that will make the most sense.

That’s it for now. Coming up will be the detailed final design, building permits, and negotiations with banks and the builder. We’re planning to start construction in early April.

Jack Partridge, 11/24/07


Building A Straw Bale House: Concept to Construction


Since I was a little girl, my dad has been indoctrinating me with a love and respect for the environment. He’s a true outdoors-man and conservationist and has been recycling, composting, shutting off the lights and turning down the heat since before it was easy or cool, despite the (occasional) aggravation of his family. Now that he and my mom are getting close to their retirement years, he has decided to take his environmental consciousness to the next level. About a year ago he began researching and making plans to build an energy efficient straw bale house in the East Mountain area outside of Albuquerque, New Mexico. The ultimate do-it-yourself-er (and all around smart ninja), he has designed a home and written his own software program to lay out preliminary building plans and model a dynamic energy balance for the house. With the model done and property bought, he is now moving on to the next stages of development. He has handed his conceptual designs over to an architect to get final design and construction drawings and he is working with a builder in Albuquerque who has experience in straw bale construction. This weekend he will be visiting the site in New Mexico. I asked him to say a few words (I got more than a few) for green.mnp about his concept, design and software:

Solar House Software
I’m a software developer. This house project has many aspects where software can help – creating building designs and plans, analyzing energy systems, and keeping track of the many kinds of information and resources involved in a construction project. So I’ve developed my own “House” software, which is geared to the design and building of an energy efficient solar house. It’s a combination of a people and resources organizer, an architectural drafting program, a building project estimator, and a solar heating and cooling energy analysis program.


Energy Design
The principles of passive solar heating are very simple: heavily insulate the building envelope, include a lot of thermal mass inside the insulated space, and put most windows on the south side, with overhangs or landscaping for summer shading. Depending on where you are located, these simple elements can greatly reduce or even eliminate your fuel use and heating costs. A big step in reducing your carbon footprint.

Ever since I started focusing on this project I’ve been horrified to notice how most of our current housing stock totally ignores passive solar design principles. Drive around almost anywhere and look at the windows on the houses. You will see virtually no orientation to the sun. This should change drastically, at least for new construction, if we are to start doing our part on global warming.

South elevation

One of the books I found most helpful on energy design was The Passive Solar House, by James Kachadorian. He is an engineer, and he includes all the information and tables you need to perform a rough energy analysis of passive solar heating. He advocates a system of storing heat energy in the thermal mass of a concrete slab resting on a bed of cinder blocks. The cinder blocks are arranged to form channels through which air circulates, storing heat energy in the slab or pulling from it, depending on the time of day and the season. The ability to store and retrieve thermal energy is important in a passive solar design, to even out the temperature swings during the 24 hours of the day. So I included a cinder block based slab in my initial designs.

Starting with some of Kachadorian’s energy calculations I began writing energy analysis into the program. To cover some additional aspects I had to give myself a crash course on heat transfer engineering. The program now uses the accepted principles of modeling the “heat energy balances” of the outside surfaces, inside surfaces, and room air temperature. And it allows me to model different strategies and systems of heating and cooling.

An energy analysis is just not a simple thing. You are looking at lots of variables and how the all interact. I groped around for a while with how to display and evaluate the findings. What I arrived at was a graph showing room temperature, and the temperatures of the walls, thermal mass, etc. over the 24 hours of a day. By viewing this graph under various scenarios I can evaluate a range of design options and solar strategies for both winter and summer needs.

Focus first on the green line – room temperature. It shows the large temperature swing (about 8 degrees) of the basic passive solar, without running air through the cinder block channels in the slab. The temperature swing would be much greater without all the passive thermal mass in the slab and interior cinder block walls.

The green room temperature line shows that running the room air through the slab can moderate the highs and lows some, but only reduces the temperature swing from about 8 degrees to about 6 degrees.

East Mountain Energy Strategy
I’ve come to feel that our chosen location in the East Mountain area of greater Albuquerque has one of the easiest possible climates for a solar home. While the winter temperatures can get down in the teens at night, there is plenty of sunshine for solar heating. With good insulation and some thermal mass there is no problem bringing in enough passive solar heat. The main heating problem is avoiding too much temperature swing – overheating in the afternoons.

And, being at a higher altitude than Albuquerque itself, the summer temperatures never get above the nineties – ok, so far! But more importantly, they always fall to the low sixties or below at night. That means that cool night air can be brought in and absorbed by the thermal mass, which then will keep the house comfortable through the heat of the day.
This all sounds fine in principle, but the real test is quantitative. Can the winter and summer temperature swings inside the house be kept within an acceptable range. That’s where the 24 hour graph tells the tale for each scenario – each combination of outside temperature range and heating or cooling strategy.

From cinder block slab to hot water tank.

What the 24 hour graphs showed was that the cinder block slab system did only a moderately good job of evening out winter temperature swings. I could have a range of around 8 degrees – say 71 in the early morning and 79 in mid-afternoon. That might be fine or it might be a little much – hard to say until you live in it!

But I also began to realize that there was not enough extra heat storage to do much about cloudy days. I would need to burn some kind of fuel for the cloudy or stormy times. This is not the end of the world, and I enjoy using a wood stove. But I also liked the idea of getting as close to 100 percent solar as possible. So I looked into using a set of solar collectors on the roof and a large water tank for thermal storage. Water is a much more efficient and flexible medium for storing heat energy than cement. Running hot water through tubing in the slab to provide radiant heat is a well accepted technique. And I liked that using such a system would also provide domestic hot water. The big benefit was that I could store up enough heat for several days of cloudy weather, depending on the size of the water tank. A bonus was that I knew Miki would love to have a spa, and the spa would make a good “heat sink” for the excess hot water generated in the summer.

So I tweaked the software to model this system as an alternative to the cinder block slab. This “active” solar system adds to the initial cost, though that cost is partly offset by eliminating the slab cinderblocks. Combined with the basic passive solar design, it provides much better temperature control (around a 3 degree swing), all our hot water, heat for two or three cloudy days, and heat for the spa. As a result, I feel that the hot water system is best for us. It will be more expensive to install, but cheaper to run and more environmentally friendly.

Here’s the water tank system with the pump (red dots) providing radiant heat via the slab in the late night and early morning hours, and the outside vent (blue dots) removing excess heat in the afternoon. The green line shows the three degree temperature swing.

This is where things stand now. I need to verify or calibrate my energy analysis against a reliable commercial or government program. I’m working with an architect to turn my conceptual plan into a finished design and construction drawings. I also have a builder in Albuquerque who is experienced with straw bale construction. We start with the garage this fall, and then the main construction next year. I’m planning more installments of this article to document the building process. I would welcome any comments or suggestions.

-Jack Partridge, Bahama, NC
Be expecting more posts on the progress of my dad’s straw bale house over the next weeks, months…year. I am especially excited to get to construction time, when we will all go out to New Mexico to help stack up the straw bale frame. Building the house will be a whole family & friends affair.
I know this is a long post already, but here is a great video from that dispels some of the myths about straw bale construction, as well as showcases some beautiful straw bale homes:

SIEEB Solar Energy-Efficient Building


So, this project is just siiick – on some futuristic, super-dynamic looking green design. The Sino-Italian Ecological and Energy-Efficient Building (SIEEB) at Tsinghua University in Beijing was designed to maximize both passive + active solar efficiency – using a push/pull effect in the stacking of floors to create overhangs and setbacks for passive solar, and an impressive photovoltaic system consisting of over 1,000 square feet of PV panels.


This stepping south-oriented facade creates a trellis-like canopy system with the photovoltaics – along with some plantings – to both shade/passively cool the building, while maximizing the amount of south-facing PV installed. The hanging plants also contribute to offsetting [if only slightly] the CO2 produced by the building, which the architects [Mario Cucinella] already have to a minimum through the use of gas engines with electric generators to account for the remainder of the building’s energy needs [after the PV].



::via Inhabitat::