David, thanks for covering this important issue in such a clear way. RECs were important to starting the shift to renewables, but they are clearly distorting the market for firm, clean power and need to be replaced.

And thanks for finally bringing geothermal into the discussion. It has been a 24/7, clean, low footprint resource for a long, long time that for some reason is always left out of the climate conversation. I would argue that it's only been a niche play because it is absent from the discussion and doesn't have any real advocacy.

And it's not just about electric power! In most places, 50% of energy use is for heating; electrifying that load is going to worsen grid and transmission issues. District heating and other direct use geothermal use cases have a HUGE role to play here.

If you include ground source heat pumps as an incredibly efficient way to get off fossil fuels for residential heating and cooling without driving massive demands on the grid, then geothermal has value everywhere on the planet. Certainly everywhere in the US.

Keep up the great work!


Expand full comment

Thanks for a great post which has given me, as you often do, a lot of food for thought. It makes me wonder if the rationale for PPAs also applies to long term contracts for purchase of renewable natural gas credits.

Expand full comment

David, thank you for this article--lots of new info for me.. Flagging one typo for you if you haven't already caught it:

That gave developers more confidence and has prompted a surge of building of clean energy projects. In 2020 alone, C&I buyers in the US procured 10.6 gigawatts of renewable energy, which represents a third of all renewables capacity added in the country. Voluntary procurement by the C&I sector become a major driver of the energy transition. 'procurements become' or 'procurement becomes (or will become).

Expand full comment

If possible, please ground truth this technology with respect to products that fill the gaps? Or perhaps as a primary green source that does not create gaps....


Expand full comment

David, I loved this piece. I learned so much. I'm grateful. I'm excited for the follow-up!

Expand full comment

Glad to see this in-depth write up and that it's catching on. My own assessment from earlier this year is that it's definitely the way to go at the moment in terms of making carbon-free commitments more impactful. - https://climaticthoughts.com/clean-power-generation

Expand full comment