ontract Manager




Ann Peterson

Building End-Use Efficiency Team
Leader







Nancy Jenkins

PIER Energy Efficiency Research Office
Manager







Martha Krebs, Ph.D.


Deputy Director


ENERGY RESEARCH AND
DEVELOPMENT DIVISION







B.B. Blevins
Executive Director


DISCLAIMER

This report was prepared as the result of work sponsored by the
California Energy Commission. It does not necessarily represent the
views of the Energy Commission, its employees or the State of
California. The Energy Commission, the State of California, its
employees, contractors and subcontractors make no warrant,
express or implied, and assume no legal liability for the information
in this report; nor does any party represent that the uses of this
information will not infringe upon privately owned rights. This report
has not been approved or disapproved by the California Energy
Commission nor has the California Energy Commission passed
upon the accuracy or adequacy of the information in this report.

i
Acknowledgments
This work was supported by the California Energy Commission through its Public Interest
Energy Research (PIER) Program on behalf of the citizens of California and by the Assistant
Secretary for Energy Efficiency and Renewable Energy, Office of Building Technology, State
and Community Programs, Office of Building Research and Standards of the U.S. Department
of Energy under Contract No. DE-AC02-05CH11231.
We are indebted to Chris Scruton and Nancy Jenkins of the California Energy Commission and
Marc LaFrance of the U.S. Department of Energy for their invaluable guidance, enthusiasm, and
support throughout this multiyear project. We would also like to thank the following members
of our Project Advisory Committee for taking the time to provide insightful technical and
market-related input into the direction of this R&D:
Carl Wagus
American Architectural Manufacturers Association
Thomas Guarr
Gentex Corporation
Jan Berman
Mechoshade Systems, Inc.
Grant Brohard
Pacific Gas & Electric Company
Charles Hayes
SAGE Electrochromics, Inc.
Micheal Myser
SAGE Electrochromics, Inc.
John Durschinger
Skidmore, Owings & Merrill LLP
Gregg Ander
Southern California Edison
Hula Demiryont
Sytecorp
Kevin Settlemyre
The Green Roundtable, Inc.
Glenn Hughes
The New York Times
David Thurm
The New York Times
Mark Levi
U.S. General Services Administration
Thomas Mifflin
Wausau Window and Wall Systems
Thomas Mifflin of Wausau Window and Wall Systems provided enthusiastic and dedicated
guidance, engineering support, and materials for our electrochromic field test facilitys
curtainwall system, without which this project probably would not have gotten off the ground.
SAGE Electrochromics, Inc. also remained dedicated throughout the duration of this project,
providing technical assistance and product revisions to meet our demanding project
requirements.
The project team consisted of staff from a variety of disciplines within the Environmental
Energy Technologies Division at the Lawrence Berkeley National Laboratory:
Andre Anders, Ph.D., Material Scientist, Thin Film Coatings
Zachery Apte, IR Laboratory Tests
Robert Clear, Ph.D., Human Factors, Statistical Analysis
Dennis DiBartolomeo, Systems Engineering, Field Test Operations

Luis Fernandes, Ph.D., Radiance Mathematica Optimizations
Daniel Fuller, Testbed Networking and Communications
Howdy Goudey, IR Laboratory Tests, Curtainwall Engineering, Sensors and Instrumentation
Chuck Hambelton, Curtainwall Engineering, Sensors and Instrumentation
Philip Haves, Ph.D., Commercial Building Systems, HVAC Interactions
ii
Vorapat Inkarojrit, Ph.D., Human Factors, High-Dynamic-Range Digital Imaging
Joseph Klems, Ph.D., Heat Flow Monitoring and Thermal Analysis
Christian Kohler, Window Modeling, Testbed Networking and Communications
Judy Lai, Radiance Modeling
Eleanor Lee, Co-Principal Investigator
Steve Marsh, Curtainwall Engineering, Sensors and Instrumentation
Robin Mitchell, Window Modeling
Thomas Richardson, Ph.D., Material Scientist, Electrochromics
Micheal Rubin, Ph.D., Material Scientist, NFRC
Francis Rubinstein, Lighting Controls, IBECS Networking and Controls
Stephen Selkowitz, Principal Investigator
Charles Taberksi, Facilities Management, Testbed Facility Engineering and Construction
Duo Wang, Data Analysis
Peng Xu, Ph.D., Commercial Building Systems, HVAC Interactions
Mehry Yazdanian, Heat Flow and Data Analysis

Our team also included colleagues from other institutions and companies:
Ren Andersen, Ph.D., National Renewable Energy Laboratory
Oyvind Aschehoug, Ph.D., Visiting Professor, Norwegian University of Science and
Technology, Trondheim
Thibaut Falcon, École Nationale des Travaux Publics de l'État, Field Testing and
Instrumentation
Lixing Gu, Ph.D., Florida Solar Energy Center, Testbed Facility Engineering
Aslihan Tavil, Faculty of Architecture, Istanbul Technical University, Turkey
Greg Ward, Anyhere Software, Radiance Mathematica Optimizations, High-Dynamic-Range
Digital Imaging










Please cite this report as follows:
Lee, E.S., S.E. Selkowitz, R.D. Clear, D.L. DiBartolomeo, J.H. Klems, L.L. Fernandes, G.J. Ward,
V. Inkarojrit, M. Yazdanian. 2006. Advancement of Electrochromic Windows. California Energy
Commission, PIER. Publication number CEC-500-2006-052.
iii
Preface
The Public Interest Energy Research (PIER) Program supports public interest energy research
and development that will help improve the quality of life in California by bringing
environmentally safe, affordable, and reliable energy services and products to the marketplace.
The PIER Program, managed by the California Energy Commission (Energy Commission)
conducts public interest research, development, and demonstration (RD&D) projects to benefit
the electricity and natural gas ratepayers in California. The Energy Commission awards up to
$62 million annually in electricity-related RD&D, and up to $12 million annually for natural gas
RD&D.
The PIER program strives to conduct the most promising public interest energy research by
partnering with RD&D organizations, including individuals, businesses, utilities, and public or
private research institutions.
PIER funding efforts are focused on the following RD&D program areas:
Buildings End-Use Energy Efficiency
Industrial/Agricultural/Water End-Use Energy Efficiency
Renewable Energy Technologies
Environmentally Preferred Advanced Generation
Energy-Related Environmental Research
Energy Systems Integration
Advancement of Electrochromic Windows is the final report for the Advancement of
Electrochromic Windows project, contract number 500-01-023, conducted by the Lawrence
Berkeley National Laboratory, Berkeley, CA. The information from this project contributes to
the PIER Building End-Use Energy Efficiency program.
For more information on the PIER Program, please visit the Energy Commissions Web site at
www.energy.ca.gov/pier or contact the Energy Commission at (916) 654-5164.

iv
Table of Contents
Preface iii

Abstract ............................................................................................................................................... viii

Executive Summary........................................................................................................................... 1

Introduction ........................................................................................................................................ 6

1.1.

Background and Overview........................................................................................... 6

1.2.

Report Organization ...................................................................................................... 9

2.0

Systems Engineering........................................................................................................... 10

2.1.

Objectives ........................................................................................................................ 10

2.2.

Approach......................................................................................................................... 10

2.3.

Description of the EC Window Prototypes and Controller ..................................... 13

2.3.1.

Manufacturer-specified EC window product characteristics............................. 15

2.4.

Description of the EC Window-Daylighting System ................................................ 16

2.5.

Outcomes......................................................................................................................... 22

2.5.1.

EC Prototype Window ............................................................................................. 22

2.5.2.

Intermediate-State EC Window Controller........................................................... 27

2.5.3.

Integrated EC Window-Daylighting Systems....................................................... 31

3.0

Performance Impacts .......................................................................................................... 40

3.1.

Objectives ............................................................