37 Erection, construction, installation, maintenance and repair of wind power systems, in particular, wind mills and wind power plants as well as of parts and accessories of wind mills and wind power plants; consultancy concerning erection, construction, installation, maintenance and repair of wind power systems, in particular, wind mills and wind power plants as well as of parts and accessories thereto; erection, construction, installation, maintenance and repair of solar energy systems, in particular, solar power installations and parts and fittings of solar energy systems and solar power installations; consultancy relating to the erection, construction, installation, maintenance and repair of solar energy systems, solar power installations and parts and fittings thereof; construction of geothermal energy installations being construction of geothermal power plants; repair of energy production plants and machines; repair of energy supply installations; maintenance and repair of energy generating installations; installation of electric light and power systems; maintenance and repair of solar power installations; installation of wind power systems; maintenance, repair of power generating apparatus and installations; providing information relating to the repair or maintenance of power generators; repair services for electric generators and wind turbines; maintenance and repair of electricity generators; construction of wind power plants; construction of solar power installations; repair for electric generators, wind power installations and solar power installations; repair and maintenance of electrical generators, wind power installations and solar power installations