λ = 0.058 W/m·K at mean temperature ((250+20)/2 = 135 °C, from the published curve). Pipe losses per metre, four thicknesses, savings vs bare.
| Pipe | 30 mm W/m | 50 mm W/m | 80 mm W/m | 100 mm W/m | BARE W/m | Surface @50 mm | Saving €/m·yr @50 mm | t CO2/m·yr |
|---|---|---|---|---|---|---|---|---|
| DN25 | 72 | 57 | 46 | 42 | 241 | 34 °C | €90 | 0.33 |
| DN50 | 106 | 79 | 62 | 55 | 436 | 36 °C | €174 | 0.64 |
| DN80 | 140 | 102 | 77 | 68 | 642 | 37 °C | €264 | 0.96 |
| DN100 | 171 | 122 | 91 | 79 | 826 | 38 °C | €343 | 1.26 |
| DN150 | 234 | 163 | 118 | 102 | 1,216 | 39 °C | €513 | 1.88 |
| DN200 | 294 | 202 | 144 | 123 | 1,583 | 40 °C | €674 | 2.47 |
| DN300 | 416 | 281 | 196 | 166 | 2,340 | 41 °C | €1,005 | 3.68 |
Assumptions: 20 °C ambient, still air (h=10 W/m²·K combined), €0.05/kWh fuel, 8000 h/yr, 82% efficiency, 0.183 kg CO2e/kWh (DESNZ 2024). Flat surfaces at this duty: bare 2,300 W/m² → 238 W/m² at 50 mm (≈€1,006/m²·yr saved). Method: ASTM C680 simplified — methodology. Your exact case: free calculator.
| Material | λ W/m·K | Loss W/m | Surface | Saving €/m·yr | t CO2/m·yr |
|---|---|---|---|---|---|
| Stone wool (mineral wool) | 0.052 | 112 | 37 °C | €348 | 1.3 |
| Glass wool | 0.050 | 106 | 36 °C | €351 | 1.3 |
| Ceramic fibre (RCF / AES blanket) | 0.060 | 127 | 39 °C | €341 | 1.2 |
| Aerogel blanket | 0.027 | 61 | 29 °C | €373 | 1.4 |
| Calcium silicate | 0.067 | 139 | 41 °C | €335 | 1.2 |
| Expanded perlite | 0.070 | 145 | 42 °C | €332 | 1.2 |
| Cellular glass | 0.058 | 122 | 38 °C | €343 | 1.3 |
| Microporous (fumed-silica) panels | 0.023 | 50 | 27 °C | €378 | 1.4 |
| E-glass needle mat | 0.050 | 106 | 36 °C | €351 | 1.3 |
| Silica needle mat / fabric | 0.055 | 117 | 37 °C | €346 | 1.3 |
DN100 pipe at 250 °C, 50 mm insulation, per metre of pipe; bare loss 826 W/m. λ at mean temperature; € and CO2 per metre·year at €0.05/kWh, 8000 h, 82% efficiency. Method: ASTM C680 simplified (h=10).
Material datasheet: Cellular glass → · temperature class: by temperature →
