This era in history may be remembered as the "Peak Age", a brief time when nearly all materials used to power and create our society reach the maximum extraction and production potential. Past this point, all of these resources become increasingly difficult to extract until they are no longer economically viable resources to be using. There are hundreds of examples of resources, currently embedded in our industrial society, which have reached their peak in the 50 years surrounding 2010, but the one which will most impact our society is petroleum.

The goal of living for 100 days without oil is to understand the extent of our dependance on oil in American society today. Specifically, how it will affect my life, as a 25 year-oil living in Minneapolis, MN. By using myself as a metric I can take a close and conscious look at where oil dependance occurs in all aspects of our daily lives : How we transport ourselves from one place to another, what we eat, how much waste we create, how water is cleaned and transported, where oil is used as; an energy resource, in conventional medicine and for hygiene and how oil affects how we entertain ourselves and communicate with others. By demonstrating how someone would be forced to live without using any oil resources, outlining both what the sacrifices will be as well as the benefits, we can can identify the many systems which will have to be re-designed in a world without cheap oil, and explore a new way of living in which we live in an energy balance.


(At the bottom of this page is a link to my version of a flow diagram of 'Where Petroleum Exists in Our Daily Lives' (using information from the Energy Information Administration-Annual Energy Review 2008 fig 5.0 Petroleum flow) click and zoom to enlarge)


Tuesday, September 21, 2010

DAY 35_PASSIVE HOUSE IN THE WOODS

18 September 2010

http://www.passivehouseinthewoods.com/

We went to tour the Passive House In The Woods today, which is located in Hudson, Wisconsin.  Yes, I had to drive there :/  First time in a car in 35 days.  But don't worry, we carpooled.  The house is a 3-bedroom, 3 level 1,940 square foot house with a rooftop terrace and many walk out balconies facing into the woods.  It is located on the edge of a cookie-cutter suburban neighborhood.  While the view from the house shows the St. Croix river valley, you have to look past all the rest of the suburban development first, which makes for an interesting contrast of building types.  We thought it should have been called Passive House in the Suburbs ;).  It was designed by a design team at TE Studio

According to their website, "The project is designed to the Passive House Building energy standard, which currently represents the tightest energy standard in the world. Passive House in the Woods actually exceeds space-conditioning requirements for Passive House by 25%.  Currently, there are a little over one dozen certified Passive House™ buildings in the U.S. The Passive House in the Woods is slated to become the first certified Passive House™ in Wisconsin, and one of only a few net energy positive and carbon-neutral buildings in the country."

The main idea for this kind of Passive House  (capital P)  is its high performance building envelope.  By super insulating with 12" of Polystyrene and 11" of Insulated Concrete Forms, the entire building envelope can dramatically reduce the amount of energy used to condition a building.  The walls have an insulation value of R-60 and the roof R-95.  The mechanical system in the house is heat-recovery ventilation, which pre-heats and pre-cools the incoming air.  Because the house has such ridiculously high insulation values, hardly any heat is allowed to escape once introduced into the space.  Electric in-floor heating mats take care of the rest of the heating, no boiler, no furnace.  While not required by the Passive House standards, the Passive House in the Woods also has two solar arrays which cover the entire electricity need and make the house net-energy positive (sells money back to the grid).  It is a 4.7 kW array which (with 4.6 hrs of peak sun in MN) I'm guessing produces about 21 kWh/day (643.6 kWh/month).  For comparison, the electric bill for my 3 bedroom house is around 180 kWh/month  (granted, the Passive House is 3 levels).  There is also a 40 square foot solar hot water collector on the roof.

It was interesting to walk through the house with my roommate Abby who designed and built a passive house (lower case p) for her parents in Alberta.  The philosophies behind the house she built and the Passive House standards(http://www.passivehouse.us/passiveHouse/PHIUSHome.html), demonstrate quite different approaches to sustainable and 'passive' building.  She designed her parent's house to have a long east-west axis with the south face oriented to the sun.  The entire south side has large expanses of windows which capture the solar energy which is stored as heat as it hits the massive concrete slab floor inside.  The BACKUP system is a geothermal radiant floor system.  It's a beautiful house which is more or less symmetrically divided to have two wings, one for her parents and one for her aging grandparents who recently moved in. 

While the Passive House in the Woods has south exposure, it seemed a bit misleading to claim that was a 'passive' feature of the house because there was no thermal mass to capture any of this solar heat/light.   The primary heating source was in-floor heating mats, and the heat recovery ventilation.  The super insulation part could definitely qualify as a "passive" system, but the rest of the systems were what I understand as "active" systems (mechanical additions to the space in the form of the Heat Recovery Ventilation, heating mats, and solar array).  In the same way, we could criticize Abby's house as not being entirely passive because it had the geothermal radiant heat.  However, Abby's house had active systems only as a backup, with the primary heating system being the passive solar energy gained through the south facing windows and stored in the concrete floor.  I'm not sure 'passive' is the right term for the method of building demonstrated in the Passive House in the Woods. 

Another thing to note is that Polystyrene is a petroleum product.  While there are many other options for insulation in buildings, how will super insulation occur without this product? What other products could be used in a post-cheap oil world to carry on this type of building? 

I'm not sure, but its seems that if a truly 'passive' system could be achieved (designing a home to capture and take advantage of the free energy resource of the sun-THAT would be a better goal than relying on the efficiency of building materials such as polystyrene super insulation + mechanical systems.

1 comment:

  1. Expanded polystyrene is 98% air... so, there is really not a lot of oil in it. It would be great to see some alternative material used though.

    Also, thermal mass and passive solar is not really well suited for your climate. The heat gained to "fuel" the Trombe wall (or floor) is equal to or less than the heat that will be lost from the interior through the windows, as the thermal gradient is so large in MN winters.

    Passive (capital P) House was developed in Northern Germany, a very similar climate to MN.

    passive (little p) solar is really best suited for climates with large temperature swings between night and day, such as the Southwest U.S.

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