maintenance and repair of pipelines supplying residential, commercial, industrial and governmental buildings and facilities; maintenance services for energy related or energy using equipment, namely, heating, cooling, lighting, and electric power generating systems and machinery including turbines, boilers, generators, chilling plants, lighting equipment and associated wiring, conduits and control apparatus, water heaters, home heating and air conditioning units, and home appliances; maintenance, repair, and recharging services for electrically powered vehicles; energy consumption reducing equipment installation; and conversion of vehicles to operate on natural gas