My college thermo class was taught by a genuine NASA scientist. He had the class work through complicated applications of all the Green energy schemes we see today. Even given the most generous assumptions none of them beat just using plane old oil-based energy.
Hydro-- and carbon-- makes for a nice word, so much more informative than "fossil fuel."
Your college instructor taught you well and effectively. It is the journalism and political science majors who "blather" on in words. Because "complicated applications" are just too complicated....
Let's all run out a burn a fossil to see how those fossil fuels actually work....