By "non-consumable", you mean on a timeframe relevant to human decision-makers?
Nuclear is non-consumable then, there's enough U6+ dissolved in the oceans to power current human energy demand for millions of years; extractable via proven technologies at a price cheaper than anything except coal, oil and gas.
Your first tech is otherwise known as "pumped hydropower". An innovative design, I'll grant you. The structural and materials challenges are prodigious, but surmountable. Able to store and dispatch over a timeframe of tens of minutes. Risk of a mass casualty event is nontrivial, and political will to permit this in a Western country indistinguishable from zero. Unfortunately. After politics; friction, corrosion and biofouling are your biggest problems, and the first two get much easier with scale.
Your second tech is a gas-to-gas heat exchanger. They work, but require maintainence and regular cleaning. Human habitations require far more airflow than that required to sustain life (odour removal, mostly), but can scale up or use complimentary technologies. I'm a fan.
Your third tech is a phase-change thermal battery. They work, at ruinously low efficiencies. Paraffin is a particularly poor choice - your delta-T is likely single figures, and your system efficiency negative.

