Posted in education
on July 28, 2014 4:29 pm EDT
Harnessing the Sun
Properly positioning a building on site can help capture the sun's natural light and save 25% on energy costs for lighting of typical commercial buildings.
While hardly anyone worships the sun anymore, the architecture community has lost a certain reverence for the power of the sun. Despite the often lack of attention paid to how a building is oriented to the sun, solar orientation totally informs the design of a building, particularly its energy efficiency, lighting, and ventilation. According to James Theimer, AIA, Principal Architect at Trilogy Architecture, properly orienting a building can save 25 percent of energy costs for lighting to typical commercial buildings. In fact, a recent school designed by Trilogy cut artificial lighting use by a whopping 90 percent.
"With HVAC responsible for the majority of energy costs, solar orientation is a valuable concept to understand and implement when designing buildings."
—James Theimer, AIA, Principal Architect, Trilogy Architecture
Allowing natural light into a building goes beyond lighting and is a major factor with heating and cooling costs. With HVAC responsible for the majority of energy costs, solar orientation is a valuable concept to understand and implement when designing buildings. Theimer notes the oft-repeated saying that air conditioning is the worst invention of the 21st century, as it allowed architects to not utilize natural processes, such as breezes and solar orientation in designing buildings. Nevertheless, taking advantage of these natural processes can lead to considerable energy savings. While how you site a building is not necessarily the “sexiest” talking point when discussing energy efficiency, according to Theimer it is the number one effort to make in energy savings over the life of a building.
The case is strong for properly siting buildings in the design stage, but what about buildings which already exist? Fortunately there are many ways to still take advantage of the sun’s power, particularly through innovative products. One of these products are Tubular Daylighting Devices (TDDs). These devices are installed in roofs and allow natural light into rooms. Solatube, Inc., a leading manufacturer in the TDD industry, highlight how TDD’s are a cost-effective, energy-efficient, and eco-friendly way to light interiors through reducing the need for electricity. Candice Clark of Solatube notes how TDDs are sophisticated devices, with their optics allowing them to gather low-angle light and adjust to shifting light patterns for more predictable light flow.
In addition, these are strong options for warm climates, as they have significantly less thermal breach than traditional skylights.
Another product is low-e glass. Below is SUNGATE 600 glass for commercial buildings.
Left: When heat gain is desired. Right: For improved U-Value. Photos courtesy of PPG.
This versatile building material is extremely popular due to its solar and thermal performance. Glass coated with this material can reflect heat while still allowing visible light to be transmitted. At the same time, this glass reflects interior heat back inside during the winter, reducing radiant heat loss through the glass. PPG is a leading manufacturer of low-e glass and is constantly producing new products utilizing this technology, leading to substantial energy savings.
Sun worship still isn’t coming back anytime soon, but hopefully by recognizing its power we can design healthier, more energy efficient buildings.
To learn more about PPG and their SUNGATE 600 glass: (visit link