Lower Cost Thermal Storage

In Ground Thermal Storage

• Day Time recharge for multi-day heat storage
• low loss thermal container
• Low cost, simple construction

Solid Phase Heat Storage

• 1/2 the volume, 1/2 cost versus salt
• Makes energy storage more affordable

Controlled Add and Release of Heat to Steam

• Conditioned Steam to the Turbine
• Separates solar from stages

Liquid storage systems like that based on salt have an advantage of maximum energy transfer as molten salt is transferred from one tank to another. The disadvantage is that two tanks are required of fairly heavy construction to accommodate the mass weight of the salt.  Even in buried systems, the tanks must be strong enough to hold back the soil as the salt is pumped out.

CSP Ultra Lite Solar’s earth based storage system only requires one relatively thin walled insulated tank that is buried in the ground.  The surrounding earth provides structural support against the weight of the storage medium in the tank, which does not vary. The disadvantage to a one tank system is diminishing energy flow as the temperatures start to equalize.  CSP Ultra Lite Solar has solved this problem by staging charging and discharging of compartments within the storage system that are separated by insulation.  This provides some of the advantage of a two tank liquid system with the economics of a one tank solid phase system.

This storage technology works best at higher temperatures up to 850 C. Central Tower and Dish based systems would most benefit from this energy storage technology. It would not be as effective for trough based systems, however, it would in hybrid plants incorporating trough technology as a preheat to Central Tower and Dish systems. Hybrid plants could have better Levelized Cost of Electricity compared to trough or tower plants alone.

Compared with traditional energy sources, Concentrating Solar systems are clean, eco-friendly and pollution-free, and could be applied to many industries requiring heat.

Controlled heating and release

Individual compartments within the insulated stainless steel storage container are computer controlled allowing for staged charging and discharging for optimum storage efficiency.

Systems can be controlled to produce the turbine specific steam temperature required.

Controls will direct heat or store heat based on energy depletion as needed.

Multi-pipe heat exchangers placed in the storage media maximizes energy transfer.

1st Heat exchanger radiates heat energy

• From solar field delivered to the storage medium
• Heat charging from top flow to bottom

2nd Heat exchanger absorbs energy

• From storage media to turbine as steam
• Heat discharge from bottom to top.

The heat exchangers are interspersed in actual deployment, but shown separately here to simplify understanding.  The Heat exchangers increase surface area contact with the storage medium to allow for effective heat transfer.