Solarflüssigkeit

Solarflüssigkeit is a liquid medium used to transport thermal energy in solar thermal power plants. In a typical solar collector the liquid—often a mixture of water and antifreeze compounds, sugar water, or special heat‑transfer fluids—flows through pipe networks exposed to concentrated sunlight. The fluid absorbs heat, which is either stored in thermal storage tanks or fed directly to a heat‑exchanger that produces steam for driving turbines. The concept is employed in both parabolic trough and linear Fresnel collectors, as well as in more advanced configurations such as cascade receivers and high‑temperature usable media.

The efficiency of a solar‑fluid system depends on the fluid’s specific heat capacity, viscosity and temperature limits. Low‑viscosity fluids reduce pumping energy, whereas high‑temperature tolerance allows higher output with the same solar flux. Commonly used media include synthetic oils, molten salts, and polymer‑based liquids. Each choice balances cost, safety, and thermal stability.

Implementing solar fluid technology offers several advantages. It decouples photovoltaic modules or mirrors from power generation, making it easier to modulate output and store excess heat. The system can meet peak demand during non‑solar periods, improving grid stability. However, disadvantages include the potential for thermal degradation, corrosion of piping, and the need for temperature‑controlled storage tanks. Moreover, the requirement for circulating pumps introduces additional energy consumption, which must be accounted for in overall plant efficiency calculations.

Solarflüssigkeit remains a key component of contemporary large‑scale solar thermal power stations, such as the 330 MW Solar Canton in Spain and the 200 MW Solar Valley plant in Germany. Continued research focuses on developing higher‑temperature fluids with lower environmental impact and on optimizing heat‑transfer surfaces to enhance capture efficiency while reducing capital costs.