Solar Retrofit - Part 5: Unexpected Consequences

Here is a diagram from the IBC boiler installation manual showing the specifications for the venting.

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Solar Awning (Part 2)

MCZNH Solar Awnings (summer and winter positions)

The Mill Creek NetZero Home (MCNZH) will have a ground-breaking solar awning installed on its south face (introduced in Solar Awning Part 1). Essentially, it's a movable awning made out of photovoltaic (PV) modules. It will serve two functions: to shade the south windows in the summer and fall, and to tilt the modules so that they are always at an optimum angle to the sun. An analysis of the solar awning's net energy benefit follows.  read more... »

Solar Hot Water

**EDIT, March 2011 **

The modelling that we did with WATSUN (and upon which this blog post was based) was completely inaccurate. It hasn't been near 100%. In January our tank sits at 20 degrees, and it fluctuates between 25 and 40 during February. Not even close to what the software promised us.

I'm not sure what happened, but modelling with WATSUN was a complete waste of time for me.

Our solar fraction is probably in the range of 60%-70%.

The Mill Creek NetZero Home (MCNZH) will collect solar energy in three different ways: using passive solar design, using photovoltaic (PV) modules, and using solar hot water (SHW) collectors. The SHW collectors are the ones that heat water - they are the black ones at the top of the above picture.

According to a recent article in Home Power magazine (Oct/Nov 2008, p.40), SHW collector efficiency is 50%-70%. That's pretty good when you consider that the best PV module is about 17% efficient.

I've been contemplating the design of the MCNZH's SHW system for months now. The pieces started to fall into place once the federal government released a crucial tool: The  WATSUN 2008 SHW System Simulator.  read more... »

MCNZH - Flex House (Part 2)

MCNZH, Second Floor. As built on the left, and "flexing" on the right.

Durability is absolutely key to sustainability. Everything we buy, every precious drop of fossil fuel that we burn, should be put to best use by creating as much value from it for as long as possible.

I see no reason why the Mill Creek NetZero Home (MCNZH) can't stand for hundreds of years. To be as useful as possible during its long lifetime, we designed it to flex with the changing needs of its occupants.  read more... »