Thursday, January 21, 2010

When did we start ignoring Passive Solar techniques?

    I recently started wondering... when did Americans start ignoring passive solar techniques? 

    I started by taking a long look at houses built in various decades.  Can you guess what these houses have in common?

    • my grandmother’s house (built in the 40’s)
    • my mother’s house (built in the 60’s)
    • our house (built in 2000)

    Here is what I realized:  None of the houses use Passive Solar Techniques to keep the houses comfortable in terms of temperature, light, or humidity.  I started asking my friends and other family members if the have windows on the south side of their house, if they have any ceiling-height windows to let out hot air, or if their west facing windows are shaded.  Most of them thought I was nuts.  (I'll admit, I may have already earned that before these questions.)

    Even though all three houses above were built with exterior wall and attic insulation, these houses must use AC and furnaces year round because they are hot during the spring, summer and fall, and they are cold during the winter. The builders paid no attention to sun orientation, window placement, geothermal mass, structural shading, and ventilation.

    So, at some point in the last 100 years, people started building the majority of the new houses with electricity, air conditioning, and heating systems. Shortly after that, people became dependent upon these systems and forgot about Passive Solar concepts.

    When energy was cheap, the answer to temperature change was a central HVAC system.  The problem now is that we are realizing that these systems use a lot of energy – not to mention that they cost a lot of our paycheck to purchase and maintain.

I want a house that uses Passive Solar energy so that I can take advantage of nature instead of fighting it. Houses that use Passive Solar energy are eco-friendly and sustainable because they use less energy and cost less to maintain. I want a house that:

a) Allows Geothermal Mass to collect sun’s energy (heat) only during the winter.

b) Allows Geothermal Mass to collect coolness from the ground and shaded areas during the summer.

c) Considers Sun Orientation to place large windows on the North and South sides of the house. Since the sun is mightier in Texas than in some other locations, I want either a porch or a wide overhang on the South side to shield the sun in our warm fall weather.

d) Uses shutters or overhangs to shield/shade windows and doors on East and West sides.

e) Provides natural ventilation to move air through the house.