The schedule calls for flipping the switch by Nov. 1 so the electricity generated by solar panels provides about 10 percent of the electricity used in four city buildings.
The solar equipment installation is one part of the city’s collaborative effort with Ameresco, a commercial company specializing in energy conservation, to reduce Englewood’s traditional energy consumption.
Over the last couple months, photovoltaic panels were installed on the civic center, the police/fire complex, the Malley Senior Recreation Center and a portion of the Englewood ServiCenter.
Ken Thames, president of Thames solar, explained how the panels were installed and how much energy they will produce to the city council at the Oct. 18 study session.
“The project involved installation of photovoltaic panels on the four buildings,” said Thames, hired as the on-site manager for installation and commissioning of the solar systems. “The layout of the modules and the number of modules installed depended on the individual building’s available roof area.”
The principal of photovoltaic is described as the use of materials made up of cells that convert the energy of sunlight into electricity at the atomic level.
Thames said each module or panel is about 38 inches by 65 inches and contains 72 crystalline cells that produce electricity. The panels are tied together in a string and the string is tied together to make an array. Again, the number of arrays depend on available roof area.
“We estimate a system operates at 80 percent efficiency because there are losses due to dust on the modules and the resistance of the wire connecting the system together,” Thames told the council. “The electricity from the system flows to a junction box and then into an inverter that coverts the direct current into the alternating current needed in the buildings.”
He said the system upkeep is easy because maintenance traditionally consists of washing the dust off the modules with a water hose.
The system on the four buildings are expected to generate about 29,103 kilowatt hours of power per month. That amount of electrical power has an estimated value of about $2,900. However, Thames said the amount of energy the system produces could be reduced where there is heavy snow and it piles up on the module preventing sunlight from reaching the modules.
Councilmember Randy Penn asked if there was a way the system could provide more than 10 percent of the electricity the city uses.
“Unfortunately, this is the best design we would devise and there is no way to expand the system because there isn’t room to add additional arrays on the roofs of these buildings,” Thames said.
Englewood developed this system as part of an overall effort to conserve energy. Under the agreement, Ameresco installed the solar system at no cost to the city and will own and maintain the system for 20 years. During that time, the company received funds from the city for the power the system produces.