The Batant is probably the best starting point to get familiar with the “many parabolas” sort of solar concentration, such as the Vesta or Helios.
It is small and designed to be easily transportable. It can be taken completely apart and fit into the trunk of an automobile.
Being smaller it can squeeze into tight places, and being transportable it’s ideal for demonstrations for whatever purposes. It’s also great for testing out concepts, before applying them to your fleet of Vestas and Apollos. Since the Batant is in our opinion an essential training, it has the most readable construction guide.