solar thermal

Observations (Part 02)

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Mill Creek NetZero Home, December 15, 2009, 14:00.

As we approach the winter solstice and the three-month anniversary of our moving in, we continue to learn about our new house. These observations are mostly qualitative, because we don’t have the rest of our solar modules up, and we haven’t set up monitoring equipment yet. We are tentatively planning to remove the door of our wood stove on July 1st, 2010  and then monitor the house’s energy use for a year.  read more... »

Observations (Part 01)

Mill Creek NetZero Home - living room

Mill Creek NetZero Home Living Room - finally some autumn sunshine!

Have you ever noticed that as soon as you move in to a solar house the sun stops shining? It’s been overcast since the beginning of October here in Edmonton – since just after we moved into the Mill Creek NetZero Home – and the fact that Edmonton has as many hours of sunshine as Miami has seemed hard to believe at times. Finally we have the return of sunny days, and the house is great to be in right now.

So what have we learned so far?

  • the transition to living on concrete floors has been painless for us. They are much warmer than I thought they would be, and since we were already in the habit of wearing Crocs around the house, I really haven’t noticed the different floor surface. We have been encouraging guests to put on a pair of Crocs from the box in the front entrance.
  • the house makes us much more in tune with the solar cycle. The above picture was taken at around 1 o’clock. I enjoyed sitting in the sun for a while before lunch, but now that I’m using the computer the sunny areas of the house aren’t appropriate anymore. Solar houses should have non-sunny areas, and the occupants must be willing to flex with what is going on outside.

Mill Creek NetZero Home - second floor library

the library area on the second floor is bathed in sunlight on a sunny day – luxurious at times, and to be avoided at others  read more... »

Solar Retrofit Part 6: Roof Reinforcements

The solar collectors on my house will not be parallel to the roof but will stand up at an angle of approximately 40 degrees.  With some of the recent wind storms around Edmonton and other places in Alberta I've been quite concerned about my house if one of those storms hits again after the collectors are up.  read more... »

MCNZH - Progress (part 7)

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The Mill Creek NetZero Home is substantially completed.

The stucco is finished on the outside. We went with a cement-based stucco because of its looks and durability.

Peter Amerongen built a brick wall behind the wood burner. We used the bricks from the foundation of the house that used to be standing on the property. This wall adds more thermal mass (to capture both solar and wood heat) to the house, as well as a bit of history.

IMG_1980  read more... »

Making water line connections in the attic

I have to make connections in my attic for the 3/4" copper pipes that do the supply and return runs for my solar thermal collectors.  I'm NOT looking forward to soldering amoung the blown-in insulation.  Someone recommended SharkBite non-soldering connectors (http://www.sharkbite.com).  The appear to have a high enough ratings (certified to 200 PSI and 93 degrees C) but I'm concerned about how they will stand up given the extreme temperature changes in the attic.  Has anyone used these connectors?  Does anyone have any experience with SharkBite fittings and solar thermal systems?

Ken 

Solar Hot Water (Part 2)

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The lessons that I learned from the computer model of our solar hot water system are as follows:

  • insulate the pipes leading from the basement to the collectors to at least R6, preferably R10
  • insulate the storage tank to R50
  • install a 1000 litre storage tank
  • install 3 collectors
  • there is extra heat - install a system to harvest it

We bought the collectors, drainback tank, pipe insulation and other knickknacks from Trimline Design Centre just down the road from the Mill Creek NetZero Home. My builder Peter was very impressed with the clever, simple design of the flat plat collectors that Trimline manufactures. Yes, that’s right, they manufacture solar hot water collectors right here in Edmonton!

Overview

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(schematic of the MCNZH solar hot water system)  read more... »

How Much Energy Does It Take To Supply Hot Water?

I read an interesting article recently about how to calculate the size of an on-demand hot water heater.  OK, while not exactly what most people would consider light reading, what I thought was interesting was how much energy it takes to generate something we take for granted.  The article discussed how running a single shower would require the incoming water to absorb energy at a rate of about 75,000 BTUs per hour and that if the tankless water heater was 80% efficient, then the heater would need to have a rated input of 94,000 BTUs per hour.  If you want the ability to run two showers simultaneously, then the numbers double so that the tankless water heater would have a rating of 188,000 BTU.  (For reference, the boiler I have for heating my house and domestic hot water can modulate  read more... »

Solar Hot Water

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... »