Canadian Winter Study (video)

Extreme temperatures during a Canadian Winter proved to be an excellent test for the ability of Solar Comfort to efficiently reflect thermal radiant heat before it has a chance to migrate through windows.

Canadian Winters can be exceptionally frigid and the weather during our cold weather hotel study was no exception.

While the test ran for nine consecutive days, the highest the temperature was 28º F and the lowest was -5ºF’.

Those were perfect conditions to demonstrate how well the radiant barrier material was able to reflect the heat pumps’ thermal heat back inside the room, slowing the natural migration of heat to the extremely cold window and then out into the environment.

During the California Heat study, it is actually easier to feel the difference the radiant barrier makes. As one stands in front of a sunny window, it soon becomes increasingly uncomfortable. When the Solar Comfort material is lowered, the drop in temperature is felt immediately. In most situations it is a reduction of 20º’s. Those dramatic changes are what gave us the impressive 54% reduction in energy costs and a more temperate interior climate.

The principle in the winter is the same as summer with the space age material working to reflect. Now the job is to reflect and retain the rooms heat, and control the rooms fluctuation in temperature, while maintaining a constant level of comfort.

Heat will always migrate to the coldest part of the room and that is always going to be your windows on a cold day.

When you feel air movement near cold panes of glass, that is the exchange between warm and cool temperatures. Since the heat will always be seeking the cold, windows provide the perfect exit opportunity. Heavy curtains can seem to flutter in this exchange but eventually the heat filters past and into the neighborhoods beyond. By hanging the barrier material close to the window the area of exchange is minimized, window efficiency increased.

The mass of the area involved in doing the reflecting is 61.4%, so the ability of the radiant barrier to control heat loss will be close to that number. During incremental data collections done during the test, power use difference reached as high as 62%.

Unlike energy from the sun which is both thermal and radiant, the thermal heat from inside a building will hit the screen at a 90º angle, hence the consistent saving results.
As the sun hits the barrier, 90º or 61.4% will be the minimum reflection and as the sun arches its way across the sky the holes elongate giving been more protection from incoming radiant energy. The reduction of solar energy can be as high as 80% in these instances.

80% of all heat movement is radiant energy. Conductive heat makes up about 5-7% and a 15% average for convection.
With those numbers in mind Solar Comfort was able to function as expected during this test.
58% or more of the radiant energy produced by the heating system is reflected back into the room which correlates to the reflective surface area which is 61.4%.

The additional unique feature of the transparent screen is that it really disappears in the window. With only a 10% reduction in visibility, the material can be hard at work while the curtains and window coverings remain open. This is especially valuable during the winter months when healthy light is at a premium during shorter days.

Study Characteristics Super 8 Hotel
High River, Alberta
Canada
February 11, 2010
Duration Nine days
Product Solar Comfort Radiant Barrier, roller blind format, 38.6% Perforation/openness rate.
Room size The rooms are 12’ X 25’ 300 SF and a total of 2400 cubic feet.
Exterior window wall 96 SF
Window size The window frame is 57 1⁄2” X 57 1⁄2”. 23 SF, 24% of exterior wall area.
Power/Data Collection EML 2020 Energy Monitor/Logger on the electrical panel.
PTAC Carrier Model 52SEE309301RC HTG @ 3540/2975 WATTS. Single Speed Fans.
Thermal Data loggers Were placed in the room 9 feet away from the PTAC on the counter.