You wouldn't happen to be sharing this builds information publicly would you? I can fully respect however if you are not.

I am a staunch DIY serial entrepreneur techie that has used my grey goo to build and sell a few companies and my time now is spent similar to yours although using a different application of physics. I too am motivated, just as you are, in my efforts to apply what I know to further reduce my energy costs which will not stop rising for quite some time.

You really made my day with this post and I hope we can find more folks like ourselves from your share because in time 'dogfooding' new ideas at home will lead to new applicable discoveries for all.

Stay Healthy!

Current state of the art in "thermal battery" aka water battery storage.

https://www.youtube.com/watch?v=IA15VkLlx-w

Its like a large freezer gel pack.

Enjoy.