Heat Pumps — Moving Heat in Both Directions

A heat pump is the cooling cycle run as a two-way machine — the same hardware that rejects heat to cool a space can absorb heat to warm one. It’s the decarbonization workhorse (electrify heating and cooling on one unit), and the small collection here points at both the mainstream challenge and the frontier alternatives to the standard compressor.

The Zotero Heat Pumps collection holds three items; the registry records titles, types, years, and links only, so each is summarized at the level its title supports:

The deployment reality — “Heat pumps show how hard decarbonisation will be” (The Economist, leader, September 2023): the technology is sound but the rollout (cost, retrofit, grid, trades) is the hard part. This is the systems-level caution that frames any all-electric plan.
Water as refrigerant (R718) — Water (R718) turbo compressor and ejector refrigeration/heat pump technology (Šarevski, monograph, 2016): water is the ultimate benign, zero-GWP refrigerant (the same one adsorption uses), but in a mechanical cycle it needs turbo-compression or ejectors to handle its very high volumetric flow at low pressure. The ejector is itself a pressure-driven pump with no moving parts — a bridge toward heat-driven operation.
Solid-state frontier — “Scientists claim solid-state heat pump breakthrough” (Cooling Post, Everitt, 2023): a reported milestone toward a heat pump with no refrigerant and no compressor, heat pumped by cycling a caloric material under a field. The registry title says only “solid-state”; the prior draft’s characterization of it as electrocaloric is not verifiable from the ingested metadata. Early-stage, but the long-run alternative to vapor compression — the physics and status are covered in Solid-State & Caloric Cooling.

Where it sits in the strategy

For a building, an air-to-water heat pump is the pragmatic all-electric default for both heating and cooling — see the 601 Delaware ATW page, which treats it as the firm baseline. The joule-heist interest is in the non-compressor options (R718/ejector, solid-state caloric) that could eventually carry load on heat or with far less electricity — the same instinct that makes adsorption attractive: get the compressor (and its electricity and refrigerant) out of the loop where you can.

Source caveat: three registry entries, metadata only — a magazine leader, a trade-news item, and one technical monograph. Confidence is medium on the strength of the monograph; nothing here is a design-grade claim.

Sources

Zotero cooling source registry — the Heat Pumps collection: Economist leader (2023), Šarevski’s R718 turbo-compressor/ejector monograph (2016), and the Cooling Post solid-state heat-pump news item (2023); title/link metadata only

Heat Pumps — Moving Heat in Both Directions

Where it sits in the strategy

See also

Sources