Steam turbine casings and exhaust frames radiate 100–300 kW when uninsulated, depending on size and exhaust-steam temperature. Removable modular covers reduce that by 85–95%, with payback 14–20 months, and allow access for inspections and blade-path adjustments without dismantling permanent lagging.
A hot turbine casing at ~350 °C can radiate ~60 kW. Removable casing covers recover around 480 MWh/year — about €34,000/year and ~115 t CO₂/year, without blocking inspection.
Verified estimate (ASTM C680 / ISO 12241). Conservative still-air basis; figures scale with size, temperature and operating hours. Estimate your exact case with the free calculator →
Steam turbines are high-value, long-service equipment that convert thermal energy into mechanical power. Yet uninsulated casings and exhaust frames lose significant heat to ambient—wasted energy that lowers overall plant efficiency and increases fuel consumption.
Exhaust frames operate at 40–60 °C when exhausting to atmospheric pressure or low-back-pressure condensers. Surface area is large (often 3–5 m² for a 20–50 MW turbine), and at 0.5 m/s ambient wind, bare loss is 40–80 kW. Over 8,000 h/yr, that is €22,000–44,000 in lost fuel value annually.
IP and HP casings operate at 150–250 °C depending on steam conditions. A typical 50 MW turbine IP casing (1.5 m³ external surface) radiates 80–120 kW bare. HP casing, though smaller, reaches 200–300 °C and may radiate 40–60 kW.
A 50 MW combined-cycle turbine with bare HP, IP, LP, and exhaust frame loses significant heat continuously across multiple casings and the large exhaust frame. The exact loss depends on your turbine geometry, steam conditions, and ambient wind speed. Use the calculator to model your specific turbine and operating hours.
Steam turbine insulation payback ranges widely depending on turbine size, operating conditions, and fuel cost. Typical ranges:
Use the calculator to input your turbine's heat-loss data, operating hours, and fuel cost for exact payback.
Turbines require periodic access:
Rigid hard lagging blocks most of this access. Removable modular covers unclip and refit without tools, allowing crews to perform inspections and minor repairs within the turbine's operating envelope—keeping the equipment insulated and efficient throughout its life.
Removable turbine insulation covers are available in high-temp fabric (rated to +600°C), with thicknesses optimized per section:
Typical result: bare 250 °C casing → ≤45°C surface (touch-safe, OSHA/EN ISO 13732-1 compliant).
Steam turbine casings experience hundreds of thermal cycles per year: cold start (ambient), ramp to operating temp (150–350 °C depending on pressure), hold at full load, then cool during shutdown. This repeated stress causes creep (permanent deformation) and fatigue of fastener preload. Hard lagging that is bolted to the casing can accelerate this by creating stress concentration points. Removable modular covers, which are unattached to the casing itself, allow the casing to expand and contract freely.
Turbine casing and exhaust losses are direct Scope 1 emissions—fuel burned to replace waste heat radiating from bare surfaces. Insulating turbine casings and exhausts is a proven Scope 1 lever with payback 11–14 months, supporting SECR reporting, ISO 50001 energy audits, and net-zero transition plans.
LP (low-pressure) exhaust frames are the largest, coldest section of the turbine (40–60 °C) and have the most surface area. Insulating this section can reduce the mechanical load on the foundation by lowering the frame's thermal gradient. Modular covers allow easy access to bearing thermometers, vibration sensors, and condensate drain systems without disturbing insulation.
Major maintenance (blade inspection, rotor balancing, bearing replacement) requires removal of the casing halves. Removable external insulation can be unclipped and temporarily stored without losing its integrity. Hard lagging often has to be cut away and discarded; removable covers are reinstalled afterward, preserving the investment.
HP and IP casings at 200–300 °C demand insulation with low thermal conductivity and minimal creep. Inzonex removable insulation uses high-performance core materials rated for continuous operation at these temperatures, with fabric enclosures rated to +600°C. This ensures dimensional stability and heat-loss performance over 20+ year turbine lifespans.
Typically 180–250 kW for a 50 MW combined-cycle unit. Exact loss depends on steam conditions, ambient wind, and casing geometry.
Typically 11–14 months for a full turbine retrofit (all casings + exhaust). Individual sections (exhaust or HP) may have longer payback (16–20 months) due to smaller heat-loss area.
Yes — removable modular covers can be installed and removed during normal operation. No shutdown, no hot-work permits required.
No — external insulation does not change rotor mass, blade geometry, or internal clearances. Vibration and balance remain unaffected.
Removable turbine covers are designed for repeated thermal cycling (cool start → full load → cool shutdown). Fabric and fasteners are rated for 10+ years of this duty.
