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Summer Energy Efficient Windows – Part3
By Solar energy | June 9, 2009
Summer Energy Efficient Windows – Part3
In the final months or my energy conservation mode, I’m beginning to gear up for the next step – Energy Efficiency. My study now revolves around windows for summer energy efficiency.
Today’s window performance rating element is visible transmittance (VT).
Visible transmittance tells you the amount of light a window allows though. Efficient windows are energy savers and will reduce my energy bill, but I still need the daylight shining into my house to keep my inside plants alive and to keep my sanity!
The visible transmittance (VT) is measured on a scale of 0 to 1. Usual values are between 0.3 and 0.8.
The higher the visible transmittance (VT) rating on the window, the more light passes inside. So for the greatest amount of daylight and to enjoy the view from your windows, the visible transmittance (VT) rating the better.
But there is a trade-off. You see, lower the VT number, the better a window insulates. To get maximum daylight transmitted inside, I lose insulating capacity.
Hmmm…I’ll have to think about this more. Perhaps some of my windows need more insulting that others.
Topics: Windows, home maintenance | No Comments »