Concentrated solar thermal coupled with PCM-rock bed thermal storage

Benefits

• Low cost thermal storage
• Output temperature ranges 550-900 °C
• Benefits industry where commercial rates for gas contract prices are above $12/GJ
• With an air receiver the storage is a single tank system
• PCM increases storage energy.

Background

Concentrated Solar Thermal (CST) can meet a wide range of industrial heat requirements. Solar thermal energy is used to produce heat which in a clean green and economical where electricity or gas is expensive.

CST, without storage, has limited use outside of daylight hours. Molten salt concentrated solar plants are well suited for power generation or delivering process steam. They currently utilise a nitrate molten salt which can only operate between 250-600°C.

Pressurised Air Receivers are in pilot technology phase and can reach temperatures up to 1000°C.

Technology

While CST systems can be designed for effective and efficient use of thermal energy, there are periods where excess heat could be stored in low cost ‘packed bed’ filler material. Our system can store and dispatch heat for industrial processes when required at temperatures between 550-900°C.

The coupling of an air receiver with a packed bed storage system provides high temperature heat for mining/manufacturing while providing the same level of reliability as gas at a lower cost. By filling the air pockets in the filler material with a phase change material (PCM), the system is able to store three to five times as much energy as the rock-bed only system.

Potential markets

The technology is ideal for pre-heating or high temperature applications such as:

• Ore preheating
• Copper refining
• Calcination of limestone
• Calcination of magnesia
• Thermal treatment of mine waste (mercury etc).

Partnering opportunities

We are seeking co-development partners and technology licensees for the further development of this opportunity.