Solar energy has been growing steadily for years and continues to expand across the world as a key part of the renewable energy mix. As materials suppliers, we support the solar sector with high-performance tube solutions for both Concentrated Solar Power (CSP) and the Photovoltaic (PV) panel production supply chain.
Concentrated Solar Power (CSP)
CSP systems generate electricity by concentrating sunlight to produce heat, which drives a steam generator or engine. The scale of CSP projects continues to grow, with solar towers and parabolic troughs leading the way. Most new plants feature molten salt storage, enabling reliable, around-the-clock energy supply.
Applications:
- Receiver tube (Parabolic trough): Curved mirrors focus sunlight onto absorber tubes, which must resist corrosion from synthetic thermal oil or molten salt.
- Receiver tube (Solar tower): Heliostats reflect sunlight onto a tower-top receiver, heating molten salt for energy storage and steam generation. Extreme temperatures and corrosion demand highperformance nickel alloys.
- Steam tracing tube (Flowlines): Steam tracing lines maintain molten salts in liquid state during night, startup or downtime to ensure ongoing performance.
- Steam generator tube (Heat exchanger): Must handle thermal oil inside and concentrated sunlight outside.
- Molten salt & steam (Heat exchanger): Need higher alloyed tube offering good corrosion resistance.
- Electric heater tube: Electric tracing lines require high-alloy materials for strong corrosion resistance.
Key material challenges for CSP:
- High temperature creep
- Thermal fatigue
- Corrosion in molten salts
Key grades CSP:
- Primarily nickel-based alloys: Alloy 625 (Sanicro® 625) and Alloy C230 in receiver, Alloy 825 (Sanicro® 825) in electrical heaters, Alloy 600 (Sanicro® 600) as MIC tube.
Photovoltaic (PV) / Polysilicon Production
Polycrystalline silicon is the raw material used to produce photovoltaic solar cells – the panels commonly seen on rooftops or solar farms, converting sunlight to electricity.
Polysilicon is manufactured at high temperatures using heat exchangers of various sizes and in different stages. The third-line heat exchangers in polysilicon production are particularly prone to severe corrosion, prompting many manufacturers to switch from standard stainless steels to more corrosion resistant alloys.
Key material challenges for polysilicon production:
- High-temperature creep
- Stress relaxation cracking
- Corrosion from trace chloride-containing environments.
Applications:
- High-temperature tubes for polysilicon production reactors
Key grade:
- Sanicro® 31HT, SAF™ 2205
Alleima has a proven track record of supplying tubing for polysilicon projects in China and India. For further information, please contact us.