SOLID is an Austrian solar engineering company specializing in all aspects of large-scale solar thermal energy plants. Since 1992, SOLID has been planning, building, delivering, assembling and operating large-scale solar plants around the world, providing hot water, room heating, industrial process heat and district heating for towns and villages. SOLID also designs and builds solar chilled water plants, including the largest commercial solar cooling projects currently in operating. The project sizes today are typically in a range from 300 kWthermal up to several MWthermal nominal capacity. With its unmatched experience in design and operation of large-scale solar plants, SOLID is both a pioneer and one of the world’s leading companies in the solar industry.

Service portfolio

We offer our customers the following:

  • Large-area collectors
  • Mounting systems
  • Pipeline construction
  • Pump units and other components
  • Controllers
  • Complete assembly
  • Planning + Design



SOLID only uses products that conform to the very latest state-of-the-art. By offering the most advanced remote control and maintenance systems available, SOLID will, at the customer’s request, assume responsibility for ensuring efficient and optimised operation of the solar plant.

Research and development

SOLID is an integral constituent and an initiator of numerous research and development projects, ranging from completed International Energy Agency tasks to other ongoing R+D initiatives – our know-how is in demand!

International network

We boast an international network with local partners in many countries around the world.