I've also been following the work of Supercritical, who are tackling the high costs of deep drilling needed (in most locations) for geothermal energy.
https://www.thinkgeoenergy.com/disruptive-drilling-technolog...
https://www.thinkgeoenergy.com/disruptive-drilling-technolog...
[1] https://en.wikipedia.org/wiki/Supercritical_water_oxidation
There are the usual adds, but nothing unusual in that respect. Seems like a pretty good summary.