ENERGY SAVINGS FROM WINDOW SHADES

This report by the Rocky Mountain Institute (RMI), prepared for Hunter Douglas, evaluates the energy savings potential of insulating honeycomb window shades in U.S. residences. Using EnergyPlus simulations across eight ASHRAE climate zones, the study finds that these shades can significantly reduce heating and cooling energy consumption, improve thermal comfort, and lower peak electricity demand, with existing homes seeing greater benefits than new homes.

• Insulating honeycomb shades can significantly reduce residential energy use, with existing homes experiencing higher savings than new homes. In cooling-dominated climates, savings for existing homes are more than triple those of new homes in absolute terms.
• The maximum energy bill savings for a 2,400 square foot home using Duette Architella Trielle shades (production fit, Green Mode) vary by city: in new homes, savings range from $60 in San Francisco to $180 in Phoenix and Washington D.C.; in existing homes, they range from $260 in Anchorage to $830 in Phoenix.
• Cooling energy reductions are generally higher than heating reductions as a percentage of total load because direct solar gain is the largest factor in cooling loads. In contrast, heating loads are shared between window conductive losses, wall conductive losses, and infiltration.
• Operation schedules are critical to energy performance. In Denver, keeping shades always closed increases heating energy by blocking passive solar heat, while the 'Green Mode' schedule balances thermal optimization with daylight needs but reduces cooling savings by half compared to keeping shades closed during all cooling hours.
• In Denver, shading west-facing windows is the most effective strategy for reducing peak electricity demand during summer afternoon hours, providing nearly the same effect as covering all windows on all orientations.
• High-performance window shades can allow for the downsizing of air-conditioning equipment. In existing Denver homes, they can reduce the design cooling load by approximately 0.5 tons, potentially allowing for a smaller A/C unit size increment.
• In some locations and under specific schedules, adding insulating shades can provide more annual energy savings than replacing windows with IECC 2012 compliant windows because shades provide a higher R-value when closed and allow for beneficial winter solar gain when open.

APA

RMI (2015). ENERGY SAVINGS FROM WINDOW SHADES. https://rmi.org/app/uploads/2017/05/EnergySavingsFromWindowShades_FinalWebReport.pdf

Chicago

RMI. ENERGY SAVINGS FROM WINDOW SHADES. 2015. https://rmi.org/app/uploads/2017/05/EnergySavingsFromWindowShades_FinalWebReport.pdf.

Wikipedia

{{cite report |author=RMI |title=ENERGY SAVINGS FROM WINDOW SHADES |date=10 October 2015 |url=https://rmi.org/app/uploads/2017/05/EnergySavingsFromWindowShades_FinalWebReport.pdf |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{rmi2015energy, author = {{RMI}}, title = {{ENERGY SAVINGS FROM WINDOW SHADES}}, institution = {RMI}, year = {2015}, month = oct, url = {https://rmi.org/app/uploads/2017/05/EnergySavingsFromWindowShades_FinalWebReport.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }