Direct exchange is always cheaper where temperatures line up. Heat pumps earn their capex when you must LIFT low-grade heat (30–80 °C) to process level (100–160 °C) — modern industrial units reach COP 2.5–4.
From our guide: Heat Recovery Systems for Industry — full context, charts and sources there.
Boilers, kilns, heat exchangers, valves and steam lines lose energy continuously. Inzonex makes patented (UK GB2508992.1) removable modular insulation — snap-fastened covers engineered per temperature tier, not generic off-the-shelf jackets: