Low Cost Energy Saving Solid‐State Smart Windows - Final Project Report

Publication Number:    CEC-500-2013-026

Abstract:

Dynamic, electrochromic or “smart” windows can switch between a clear and tinted state on demand to block direct sunlight and radiant heat in the summer and n transmit radiant heat in the winter. These windows can transmit ambient light from indirect sunlight year‐round to reduce energy use associated with lighting and air conditioning California buildings. Electrochromic windows darken when energized by an electrical current and turn clear when the voltage is taken away. Existing dynamic windows have fallen short of the cost, performance, and quality requirements needed for wide‐scale market adoption.

The overall goal of this project was to develop a new approach to manufacturing electrochromic windows at a reduced cost using an all‐vacuum in‐line production process. An all‐vacuum inline production process requires only one vacuum step and is significantly less expensive than the traditional process.

The project accomplished its goals and resulted in a new manufacturing process that produces electrochromic windows at a substantially lower cost. These windows are now commercially available. Since commercial and residential buildings annually consume about 40 percent of the energy used in California, electrochromic windows could reduce the energy and cost associated with lighting, heating and cooling buildings. In existing commercial buildings, assuming a 10 percent market penetration, this technology could save California ratepayers more than 500 gigawatt hours (GWh) a year, which translates to more than $65 million annually in reduced lighting energy costs alone.

Author(s):  Robert Rozbicki

Commission Division:    Energy Research and Development (500)

Office/Program:   

PIER Program Area:    Buildings End-Use Energy Efficiency

Date Report Completed:    August 2012

Date On Line:    07/30/2013

Acrobat PDF File Size: 28 pages, 1,000 kilobytes**