Compliance + TEWI in one click
By DigiEntropy Engineering · 2026-02-14 · 6 min read
F-Gas direct emissions + indirect kWh emissions + GWP + safety class + EN 378 charge limit, all in one regulatory verdict and one PDF. The Compliance page is the slide auditors and sustainability committees actually look at.
About this post — Authored by an AI assistant using DigiEntropy's polynomial corpus, the universal compressor predictor, and the project's chart-generation tooling. Charts are produced by Python scripts that read the same database the live site queries; tables and formulas are pulled from the same engineering modules. Findings reflect the project's current dataset and methodology — send corrections or deeper questions to admin@digientropy.com. Project specs land with regulatory questions: does this system meet the F-Gas Regulation? Is the charge under the EN 378 limit for the room volume? Is the lifetime CO2 footprint defensible to the sustainability committee? What's the GWP-weighted F-Gas quota exposure? Each of those questions has a dozen sub-questions. Most engineering tools answer one. The Compliance page answers all of them in one verdict, with the breakdown rendered as a PDF ready for the regulatory file. What it checks Regulation What it verifies ------ EU F-Gas 2024/573 GWP under the threshold for the equipment category; quota CO2-eq is within the allocation window EN 378-1 Refrigerant charge ≤ practical limit for the room/occupancy class (A/B/C access tier) ASHRAE 15 Refrigerant Concentration Limit (RCL) for the room/occupancy class — US analogue of EN 378 ASHRAE 34 Refrigerant safety classification (A1/A2L/A3/B1/B2L/B2/B3) tagged against the actual fluid Eco-design (when applicable) Seasonal coefficient minima for heat pumps, AC, commercial refrigeration TEWI Total Equivalent Warming Impact across the system's lifetime: direct (charge × GWP × leak rate × years) + indirect (annual kWh × grid CO2 intensity × years) The page runs all six in one pass and renders the pass/warn/fail per regulation. TEWI — direct vs indirect The TEWI calculation: $ TEWI = \underbrace{\text{charge} \times GWP \times \text{leak rate} \times \text{years}}{\text{direct emissions}} + \underbrace{\text{annual kWh} \times \text{grid CO2 intensity} \times \text{years}}{\text{indirect emissions}} $ For most refrigeration systems in 2026: - Direct dominates for high-GWP HFC systems (R404A, R448A). A 50 kg R448A charge with 5 % annual leak over 15 years = 50 × 1387 × 0.05 × 15 = 52 t CO2-eq. - Indirect dominates for low-GWP systems (R744, R290) and for any system in a high-emission grid. The same 50 kW MT load running 5000 hours/year at COP 2.5 = 100 MWh/year × 0.3 t CO2/MWh × 15 years = 450 t CO2-eq. So even on an R744 system with zero direct emissions, the 450 t indirect dominates. Energy efficiency matters more than refrigerant choice for lifetime CO2, except in the…