According to google, this would be almost 30% of total US energy production (135gw-150gw) and nearly 5% of total US energy consumption.

But what is the "breakthrough" if there is one? The article doesn't really suggest any breakthrough that is unlocking this potential energy? Or maybe I'm looking for a technological breakthrough where there isn't one.

There isn't one. They are trying to politically pressure a utility to build some geothermal plant. But utilities have engineers who will tell their bosses that this plan doesn't work. So the companies selling the geothermal plant are trying to politically pressure the utility to do yet another thing that they know won't work. PG&E for example has several geothermal plants which have been economic disasters and were and are being shutdown.

My understanding is that it's due to better drilling techniques. The industry learned a fair bit from fracking and they're learning more from experience as they apply it to geothermal.

No particular breakthrough, but there's a learning curve and they learn more as they do more. Other industries sometimes work that way, too.

https://www.austinvernon.site/blog/geothermalupdate2026.html

4th paragraph of TFA:

> Several companies are now building upon existing techniques for accessing geothermal resources by integrating enhanced geothermal systems (EGS) into operations. While conventional geothermal systems produce energy using hot water or steam, pumped from naturally occurring hydrothermal reservoirs trapped in rock formations underground, EGS use innovative drilling technologies, such as those used in fracking operations, to drill horizontally and create hydrothermal reservoirs where they don’t currently exist.