Solar thermal plants utilize the heat from the sun's rays. The sun’s rays are concentrated via reflectors in an absorber to heat a fluid that generates water vapor using a heat exchanger. The water vapor is used to drive turbines and generators as in conventional thermal power plants. Solar thermal power plants include parabolic trough, Fresnel and solar tower power plants. Dish Stirling power plants are a special variant where concentrated sunlight directly drives a Stirling engine that in turn drives a generator.
In systems where the sun's rays are concentrated from heliostats on absorbers in solar towers, the tracking systems of the mirrors must be moved with high precision and high accuracy. The bearing supports must operate using the lowest possible friction and high rigidity.
Improved performance in tracking systems with high-precision bearing supports
Rolling and plain bearings such as maintenance-free half shells with a metal-polymer composite sliding layer are used in tracking systems. In parabolic trough structures that can measure almost 200 meters in length, they minimize the torsion of the long axis that compromises the reflection of the sun's rays on the absorber pipes.
Schaeffler supplies rigid angular contact roller bearings with high load carrying capacity for two-axis gearboxes for heliostats that measure 120 m², for example. These components enable the high loads generated by the weight of the mirrors and wind forces to be reliably supported. This means the power plant precisely tracks the sun's path.