E-glass needle mat at 300 °C — heat-loss table

λ = 0.053 W/m·K at mean temperature ((300+20)/2 = 160 °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	81	63	51	47	294	35 °C	€112	0.41
DN50	119	89	69	62	530	38 °C	€215	0.79
DN80	158	115	87	76	782	39 °C	€325	1.19
DN100	193	137	102	89	1,005	40 °C	€424	1.55
DN150	265	184	133	114	1,480	42 °C	€633	2.32
DN200	332	227	161	138	1,927	43 °C	€829	3.04
DN300	470	316	219	185	2,849	44 °C	€1,236	4.52

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 2,800 W/m² → 267 W/m² at 50 mm (≈€1,235/m²·yr saved). Method: ASTM C680 simplified — methodology. Your exact case: free calculator.

Context

All materials at 300 °C

Material	λ W/m·K	Loss W/m	Surface	Saving €/m·yr	t CO2/m·yr
Stone wool (mineral wool)	0.057	147	42 °C	€419	1.5
Glass wool	0.054	140	41 °C	€422	1.5
Ceramic fibre (RCF / AES blanket)	0.060	154	43 °C	€415	1.5
Aerogel blanket	0.029	78	32 °C	€452	1.7
Calcium silicate	0.070	177	46 °C	€404	1.5
Expanded perlite	0.073	184	47 °C	€401	1.5
Cellular glass	0.062	158	43 °C	€413	1.5
Microporous (fumed-silica) panels	0.023	63	29 °C	€460	1.7
E-glass needle mat	0.053	137	40 °C	€424	1.6
Silica needle mat / fabric	0.055	142	41 °C	€421	1.5

DN100 pipe at 300 °C, 50 mm insulation, per metre of pipe; bare loss 1,005 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: E-glass needle mat → · temperature class: by temperature →

FAQ

Questions on this topic

How much heat does a pipe at 300 °C lose with e-glass needle mat?

With 50 mm at 300 °C (λ=0.053 at mean): DN50 loses 89 W/m, DN100 137 W/m, DN200 227 W/m — vs 1,005 W/m bare for DN100. Full table on this page.

What surface temperature does e-glass needle mat give at 300 °C?

≈40 °C with 50 mm on DN100 (20 °C ambient, still air). Personnel-protection targets (≤45–60 °C) may need more thickness — see the 80/100 mm columns.