The real issue is heat transfer at very high temperatures, a topic on which I try to challenge him to rise higher, to make an unintentional pun.
The key to the problem to my mind is in fact my son's area of expertise, materials science, specifically nuclear materials, designed for a combinatorial optimization of strength, temperature and corrosion resistance under challenging conditions, for example, neutron and other particle bombardment.
I believe that great things are possible in this era, and he challenges me to suggest why it may be so while grounding me in concepts outlining the difficulties.
I am in favor of a concept originally suggested by the model for Dr. Strangelove, Edwin Teller, so well portrayed in the movie "Oppenheimer," the breed and burn concept, further advanced by Hiroshi Sekimoto, the Japanese nuclear scientist as the "Candle reactor" and rebranded by Terrapower as a "Traveling Wave" reactor.
In this design, the reactor would burn through its core to a stop point, whereupon it might be replaced in the energy conversion device in the way light bulbs were or are changed.
At very high temperatures, "process intensification," the use of the "waste" heat from one process to drive another increases thermodynamic efficiency and lowers cost, making energy accessible to those who lack it, and allowing us to increase the use of energy for now inaccessible tasks, such as restoring the Earth's atmosphere and oceans to healthy and sustainable levels.
By the way, I didn't know that Leon Panetta's son is in Congress, following in his father's august footsteps.
I recently saw Leon himself at a live event, a "conversation" held at Lehigh University, (with the University President) whereupon he offered meaningful musings on responsibility in Government, reflecting on his own time in Congress and in the administrations in which he served, the Clinton and Obama administrations. He spoke for the importance of human decency and sanity among leaders even those who disagree.
His mind was so clear in the conversation that I had no idea that he is in his mid eighties; he certainly didn't look it. He would have been a fine President himself, and I trust that his son, who sounds sensible from your description, will reflect the values his father held, and indeed, still holds.