How to Cut your Building's Electrical Costs with Daylighting
By Torrin Greathouse | January 30, 2018
In 2014, 19% of all the electricity consumed by the commercial sector was used for lighting alone. The lighting systems that a facility uses can have a drastic effect on its operating costs, and when you consider that the price of electricity has beensteadily rising, increasing by 63% since 2003, this can have a dramatic effect on overhead costs. Replacing electric light fixtures with well-integrated natural lighting is one of the surest ways to reduce electricity use.
Integrating daylighting can help to reduce a facility’s electrical use in two key ways.
Minimize Lighting Cost
The main advantage to daylighting is that it allows facility owners to turn off artificial lighting while the sun is up. Inefficient electric bulbs can waste between 50% and 90% of the electricity they consume, meaning that the majority of the money you spend on lighting throughout the day is wasted. Studies show that incorporating natural lighting systems for use during the day can reduce a building’s lighting costs by up to 40%.
Decrease HVAC Use
The other key way that daylighting saves electricity is by minimizing the HVAC costs of a facility.
Excess heat produced by electric lights puts a major strain on HVAC systems to maintain a comfortable interior temperature.According to one study, replacing artificial lighting with well-designed natural lighting can reduce a facility’s HVAC costs by 25% per-square-foot.
Generally, skylights are not known for their abilityto protect a building’s envelope. Traditional skylights absorb nearly four times the heat of vertical windows while allowing 35-45% of the heat to escape during cold winter months. However, modern manufacturers have worked hard to combat this issue. Well-designed skylights minimize heat loss and gain, providing free lights while minimizing the potential for elevated HVAC costs.
How Much Can You Save?
A building that integrates well-designed daylighting systems can save energy in a number of ways. Natural light minimizes electricity usage for electric lighting, HVAC and other climate control systems, fan usage, and additional costs from peak-hour demand charges. According to the U.S. Department of Energy, a facility that integrates efficient, active daylighting will save between 50-80% on electrical costs when compared to facilities which rely on electrical lighting.