Chicago Window Expert Nobody knows more about windows.

Mark Meshulam is an expert witness and consultant for windows, glass and building facades.



Your Chicago Window Expert recently had an opportunity to visit a real, working solar power plant in Richmond, California. The Richmond site, a wastewater treatment plant, now obtains one-third of its electrical energy needs from solar power.

Aside from the great story-value of a municipal agency (The West County Wastewater District, or WCWD) creating its own energy on its own land, there are interesting backstories, too.

2-axis tracker at West County Wastewater Treatment Plant

2-axis tracker at West County Wastewater Treatment Plant

For instance, the WCWD site is the largest solar power plant in the US that uses 2-axis trackers to aim the PV panels toward the sun at all times. “2 axis” means that the panels not only move East to West (the azimuth direction), as the sun crosses the sky every day, but also North-South, as the sun’s position varies over seasonal cycles.

The manufacturer of the solar trackers, as these aiming devices are called, is ET Solar. They generously arranged this tour.

Another story worthy of mention is the financial structure of the deal. WCWD entered into a contract with a “solar developer” Solar Power Partners, Inc. to furnish and install the entire installation. They, in turn, contracted with a “solar contractor”, Premier Power Renewable Energy, Inc. for the performance of the work.

A crane is used to place the assembled array onto the tracker base

A crane is used to place the assembled array onto the tracker base

The solar developer retained ownership of, and responsibility for the maintenance of, the entire installation. WCWD agreed to buy the electrical output of the plant at a predetermined rate for 20 years in a PPA – a Power Purchase Agreement.

At the end of the 20 year term, WCWD may purchase the power plant from the solar developer at market rate.

Another interesting story: the use of trackers, whether 1 or 2 axis, will be an increasingly familiar part of the PV landscape because of its ability to increase power output by 20-40%.

Land usage was also of interest. The land was somewhat unstable and prone to flooding. The trackers used a ballasted base that required little excavation, yet provided stability for the trackers up to 110 mph.

The 1.1 megawatt plant uses about 5 acres of land.

Each tracker measures approximately 22-by-36 feet each and carries 56 panels with a total peak power of about 11.24 kilowatts (kW) each. The system is designed to produce approximately 1.97 million kilowatt-hours (kWh) of electricity annually. That annual output would be enough to meet the annual needs of 3,654 California homes.

Detail and dimensions of solar tracker

Detail and dimensions of solar tracker

Now you can tread among the trackers. See our video now…

UPDATE: Chicago now has the US’s largest urban solar power plant: Excelon City Solar
Owner: Excelon (parent company of ComEd)
Location: 1201 W. 120th Street, Chicago, IL (West Pullman neighborhood)
Site is owned by City of Chicago, leased to Excelon.
It was an unused, polluted industrial “brownfield” that was off the tax rolls for 30+ years.
Now it will generate tax revenue.

Lot size: 41 acres

Excelon City Solar, Chicago. The largest urban solar power plant in the US

Excelon City Solar, Chicago. The largest urban solar power plant in the US

Capacity: 10 MW
Production: 14,000 MWH/year
Powers: 1200-1500 homes
Trackers: 2 axis guided by GPS by SunPower®
# Panels: 32,292
Jobs created for construction: 200
Ongoing jobs for maintenance: 7-8

July 2009: Site work began
December 2009: Commercial operation commenced
February 2010: All solar panels online
March 2010: All panels tested and in service
July 2010: Final site work completed.

Designer: Sun Power, San Jose, CA
Cost: $62 millionWant to talk solar?

Mark Meshulam, Chicago Window Expert, wants to discuss solar energy with you

Mark Meshulam, Chicago Window Expert, wants to discuss solar energy with you

Read the rest of this entry »

1 Comment

Generic selectors
Exact matches only
Search in title
Search in content
Search in posts
Search in pages
Filter by Categories
About windows & glass
Accident investigation
Aluminum windows
Bad replacement windows
Bad window installation
Bad window replacement
Best windows
Broken glass evidence
building design
Building Energy Benchmarking
Building envelope
Building science
caulking contractor
Construction defects
Curtainwall retrofit
Drafty windows
Energy Efficient Windows
Expert witness
Exterior facade consultant
falls from windows
Fiberglass windows
Glass breakage
Glass evidence
Glass Safety
Glass types
leaks in walls
Mockup testing
mold in walls
My windows leak
Nickel sulfide inclusion
personal injury
Preconstruction mockup testing
PVC windows
Renewable Energy
Repair or replace windows?
Replace weatherstripping
Restoring windows
Safety glass
Safety glazing
Secondary glazing
Shower doors
Shower enclosure
solar energy
Solar Power
Spontaneous glass breakage
Steel windows
Testing windows and glass
The Construction Process
Types of glass
Vinyl windows
Web statistics
Window air infiltration
Window air leaks
Window condensation
Window dangers
window falls
Window gaskets
window replacement
Window retrofit
Window safety
Window test
Window testing
Window types
Window water leaks
Window weatherstrips
Windows and Energy
Windows leak
Wood windows
Wynn Hotel

No matter where you are,
Chicago Window Expert can help you
Mark Meshulam
Email me               CV-Resume'
Brochure      Testing Credentials
Follow us on Facebook or Twitter
for updates you won't see here
View Mark Meshulam's profile on LinkedIn

Caulking & Waterproofing
Now offering caulking, tuckpointing and waterproofing services in selected areas. Contact
for details

Photo of the day

NiS inclusion chemical composition
Chemical analysis of nickel sulfide inclusion. In addition to nickel (Ni) and sulfur (S), the glass impurities also include oxygen (O), sodium (Na), silicon (Si), potassium (K) and calcium (Ca). Thanks to Jianjun Yang, Xinyi Glass and South China University of Technology for these images.


Alabama, Alberta, Arizona, Arkansas, British Columbia, California, Colorado, Connecticut, Florida, Georgia, Hawaii, Illinois, Indiana, Iowa, Japan, Louisiana, Maryland, Massachusetts, Michigan, Minnesota, Missouri, Montana, Nebraska, New Jersey, New York, North Carolina, Nova Scotia, Ohio, Oklahoma, Ontario, Oregon, Pennsylvania, Russia, Singapore, Tennessee, Texas, Utah, Virginia, Washington State, Washington DC and Wisconsin

Coming soon to you