Construction started Monday on a Palmdale solar project that will generate 1,800 megawatt hours of electricity for the city. The system by Constellation Energy Resources LLC will place 3,200 photovoltaic panels on shade structures at the Civic Center, DryTown Water Park and Marie Kerr Park. Constellation, a Baltimore subsidiary of Exelon Corp., in Chicago, is financing, building and operating the system. A price tag on the project was not immediately available. The city will buy the energy from the company. It’s estimated Palmdale will save $40,000 in energy costs the first year and help the city reach its greenhouse gas-reduction goals by eliminating 1.8 million pounds of carbon dioxide emissions annually, Mayor Jim Ledford said. “We’re also proud that we took the extra steps to make these structures more aesthetically appealing by adding color and architectural features so that they are visually compatible with their surroundings,” Ledford said in a prepared statement.