Mayor Kimberley L. Driscoll last Monday joined representatives of Wing Power Energy and Verizon Wireless to highlight a green energy trial project being undertaken by Salem and the firms as a joint effort. The project has involved installing three “hybrid” turbines on the roof of the city’s South Harbor Garage on Derby Street across from the Salem Waterfront Hotel. The turbines generate wind energy from their vertical blades and solar energy from solar panels. The energy in turn powers wireless equipment that provides broadband Internet connections to a digital signage/community billboard mounted on the exterior of the garage and surveillance cameras that have been mounted on the roof. The city-operated devices run strictly on the energy produced by the turbine, which is not connected to the regional power grid. Verizon Wireless, through its Innovation Center, in Waltham, is providing the funding and wireless expertise for the trial project, which is being undertaken at no cost to the city, according to Debra Lewis, spokeswoman for Verizon Wireless. The goal is “looking at new and innovative ways to use energy, and at the same time ways we might be able to deliver wireless service in places where traditional energy solutions aren’t possible,” Drew said by e-mail.