# Trivia : it looks like tap beer, it costs like champagne... | Airthium (YC S17)

- Canonical URL: https://wefunder.com/feed/377690
- Entity ID: wefunder:feed_item:377690
- Published at: 2026-08-31 21:33:18 UTC
- Updated at: 2026-09-01 11:19:26 UTC

## Author
Franck Lahaye

## Subject
Airthium (YC S17)

## Content
... it has an oily finish and some industrial notes.... you guessed it, it's our thermal oil :)Thermal oil is both the bloodstream and part of the beating heart of our engine. It circulates through an external loop, carrying heat between the engine’s heat exchangers and the industrial process. Inside the engine, it also acts as a liquid piston, helping compress and expand the working gas while enabling highly efficient heat transfer. It isn’t a fuel we burn, it moves heat and helps make the thermodynamic cycle happen!