The key chemistry bit:
The receiver heats a gaseous heat transfer fluid which circulates in a closed loop, delivering the high-temperate process heat to the thermochemical reactor and the thermal energy store. In the reactor, CO2, water vapour, and methane sourced from biowaste are heated with the solar energy over a catalyst which produces a mixture of carbon monoxide and hydrogen known as syngas. This is then piped down the tower to a Fischer-Tropsch unit which converts it into a synthetic crude which a refinery would then process into kerosene for planes, diesel or methanol for ships and trucks, and petrol for cars.
Super cool. Chemical fuels (hydrocarbons or even plant oils) have ridiculous energy density, which is nice for e.g. cars but absolutely crucial for fast, long-range air travel. I don’t think we’ll be saying goodbye to jet engines for a long time, and it’s awesome that we have ways of making fuel in a somewhat sustainable fashion.
The US Navy has experimented with this, but I think the idea is to use nuclear power instead of solar energy. Makes sense for an aircraft carrier with a big reactor and thirsty jets.