42 Engineering services for the construction and operation of plants for the utilization of solar energy and their components; Engineering services for research, planning, design and development of solar collectors for the provision of heat or light (photovoltaic), for individual use or for use in power plants; Engineering services for the provision of process heat, thermal heat and heat for power generation; Engineering services for the storage of heat, for the construction and operation of heat storage units; Engineering services for the construction and operation of components of solar collectors, such as concentrators, parts of concentrators, thermal absorbers, photovoltaic absorbers and hybrid absorbers, Engineering services for the construction of frames for solar collectors; Engineering services for the design of controls for the operation of solar collectors, tracking drives of solar collectors, and heat storage units and their components; Engineering services for the construction of frames for solar collectors