37 Construction, installation, repair and maintenance services for electricity, gas and all types of energy distribution networks; assembly, installation, repair and maintenance services for equipment of electricity, gas, gas pipelines, boilers, gas and electricity accessories and installations, heating, air-conditioning, ventilation and refrigeration apparatus; installation of solar heating systems; installation of solar energy systems; installation and maintenance of thermo-solar installations; underground construction services relating to pipes; management and supervision of works and building projects; underground civil engineering services; installation services for solar energy systems; underwater repair and installation services; construction of structures for the storage of natural gas and crude oil; construction of structures for the production and transport of natural gas and crude oil; drilling services for the extraction of oil and gas; repair services for gas supply systems; mining and oil and gas extraction services; underground construction services relating to gas networks and supply lines; maintenance, repair and reconditioning services for photovoltaic installations and apparatus; installation of solar energy systems; maintenance and repair of thermo-solar installations; recharging service for batteries and accumulators; charging of vehicle batteries; recharging of electric vehicle batteries; vehicle service stations for refueling and maintenance; service stations for the maintenance of vehicles; installation services of photovoltaic cells and modules.