Energy efficiency — specifically eliminating standing heat losses (insulation, steam-trap repair) which usually has NEGATIVE cost: the fuel saving exceeds the investment within ~2 years, before counting avoided carbon allowances.
From our guide: Industrial Decarbonization — 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: