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ASU (air separation unit)
What it is
The core industrial gas asset - a cryogenic plant that compresses, cools and distils air into oxygen, nitrogen and argon. It runs continuously and cannot be cycled economically
Power is typically 60-70% of operating cost, making an ASU effectively a machine for converting electricity into gas
Impact on industries
- Scale economics are steep, so larger units have materially lower unit cost and the market naturally consolidates around big plants
- Extreme power intensity means competitiveness is set by electricity tariff and reliability rather than by plant efficiency alone
- Continuous operation with high fixed cost means low utilisation is severely punishing, which is why capacity is built against contracts
- Argon and rare gases are recovered as co-products with far higher value per unit than oxygen, improving blended realisation