passive  solar 

never                                                    the power of low tech 

Good info here on passive solar home heating & design.

the  Spanish   peaks

It's not just for the beach!!

The Building Inspector said we would be "Mighty Cold" in the winter with this method of insulating. He couldn't have been more wrong. Please check out the P2000 system. You'll be "Mighty" glad you did.

  thermal  storage  tubes

We outfitted most our windows with window quilts from this company. They are an excellent investment!

  Welcome to the  Laboratory

  energy costs  for  our  humble abode

You may have noticed we were unable to follow all the passive solar design recommendations to a T. Yet, we still reap the rewards of low energy costs. 


                        average yearly cost 

           Propane        Electric            

           $475.00    $966.00               

Notes:                          For 8 KWH per day ?!


Avg 2009 Colorado home heating cost $1,600.00 per year. We use propane for water heating too. Avg Colorado electric usage is 23.5 KWH per day. Our electric usage averages just 8 KWH per day. Check out


San Isabel Electric charged an initial fee of $2,800.00 to hang the transformer from the pole, along with trenching and running the 80 feet of cable to the house. We spread this fee over the course of 5 years or 60 monthly bills.   


All except the south windows are low E, high U, and argon filled.  

The solar tube project was a unique experience. 5 of the 6 tubes are 10ft long with a diameter of 18". They are fed through holes in the wood floor and placed in a lined mote on the concrete floor below. We added an electronic moisture sensor to let us know if a leak is detected. Each 10ft, fiberglass tube holds 132 gallons of water. The 6th tube was cut shorter because a floor joist ran directly under it.


On a good, sunny, winter day, the water temperature reaches 80 to 82 degrees. When the sun goes down, we close the interior doors to insulate the windows. Then the magic begins!


Over the course of the evening, the heat captured in the tubes releases back into the air. On an average winter night, the propane stove will not come on until 4 or 5am. It will remain lit for 3 to 4 hours. If we have another sunny day, the stove will not kick on again until the following morning for another short round of heating.


And let's not forget the cooling benefits of using water for your mass. During the summer months, the water absorbs excess daytime heat. Temps at out 7,000 ft altitiude will take a 30 to 40 degree swing from day to night. This creates a great night-time cooling opportunity.


Remember how G-ma and G-pa used to do it before modern air conditioning? Right! Open the windows and cool down at night. Then, close up in the morning to hold the cooler air in. Here again the extra insulation comes into play keeping the hot air out and cool air in.


Absurd: After the first year we had a nice crop of black algae growing in the tubes. We added several different chemicals in an attempt to kill it. Nothing worked. So, we ended up having to drain them all out, scrub the insides with CLR, refill and redye.


Sensible: Disinfect your tubes before you fill them!!


Absurd: The tubes are vulnerable to horsing around. We haven't found out yet what happens if someone slams into them.


Sensible: Come up with some kind of sturdy rail to avert accidents.


Absurd: A couple days after placing our tube order, a "surprise" package arrived in the mail. It contained a patch kit for the water tubes!! Oh crap! What were we getting into?


Sensible: Using cinder blocks and pond liner, we created a containment area if a leak were to happen. The solar tubes have remained leak free...knock on wood.


Passive Solar design is the best kept 

secret for minimizing your heating and cooling costs. It takes advantage of building site, local climate, and available building materials to minimize energy use.


Go big or go home when it comes to insulation. If you rely on heating and/or air conditioning, go beyond local convention. Install at least half again as much as what convention suggests. Maybe even double!


To get the most out of your PV system,

start with a sound passive solar home design. You'll be the smartest kid on the block. 


Here’s how we tweaked our basic 28’x 36’ home kit to embrace Passive Solar principals:


• Orientation – A 36’ side of the house is not shaded and facing south.


• Glazing – Following a suggested formula, we used an effective ratio of wall to glazing to optimize heat gathered from the sun.


• Insulation – We beefed it up a bit and used a P2000 system. This approach is kind of cool to learn about as it challenges the whole “R-value” rating system. It had promised, and has proved to be a big contributor to energy savings, with only a couple inches of insulation. Our Building Inspector laughed and told us we would be mighty cold in the winter. He was old school, but signed off on the plan any way.


• Mass – another “hot” concept…and old as the hills. Ancient cliff dweller got it. Their mass was rock. Our mass of choice is water filled, fiberglass tubes residing just inside the large south facing windows. They collect heat from the sun during the day, and release it back into the house at night.


• Natural air convection – This part of the design allows passive air circulation to provide even heating. No hot spots. No cold spots. Our open floor plan is a big part of this.

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The "3 Sisters" gardening approach provides natural summertime shading for the south facing, solar windows. Corn (for flour), beans and squash.