Hybrid CSP explained
Advantages of the iQuadgen® Hybrid CSP
The Hybrid CSP plant combines CSP with gas expansion to provide cooling and additional generating capacity.
Combining a CSP plant with gas expansion at a pressure reduction station:
- Increases both the efficiency and output of the CSP plant without increasing its water consumption
- Provides a heat source for the pressure reduction station
- Saves the capital cost of expensive air cooled condensers
- Can reduce the plant footprint since the MW per acre/hectare is increased substantially
- Provides both base-load and peak demand power supply 24/7 and for 365 days of the year. (Base-load is the amount of power required to meet minimum demands based on reasonable expectations of customer requirements. )
- Has limited carbon footprint (if sustainable bio-energy used in the model with engine)
Baseload tracking means iQuadgen® CSP will balance the generation of solar electricity with the generation of electricity from the turbo expander and, if necessary, from a bio-energy based heat source to meet the demands for electricity irrespective of the time of day or time of year
This innovative hybrid plant design would reduce the development cost for a typical CSP plant from $17.5 million per MW to $5.4 million per MW at today’s prices for a typical sized plant (see table above). Adding a fuel cell or engine, running on bio-energy, to provide heat when the solar heat source is not available, could further reduce this to $4.3 million, although with increased operating cost to reflect the fuel needed to run the engine.
More Detail on the iQuadgen Hybrid CSP technology
The Hybrid CSP plant combines CSP with gas expansion. During the expansion process, performed by pressure reduction stations, the natural gas is generally pre-heated to counter the Joules Thomson cooling effect. By locating a CSP or ISCC plant close to a pressure reduction station, and using the condensation heat of the CSP/ISCC plant to meet the pressure reduction station’s heating requirements, CSP/ISCC plant developers and pressure reduction station owners can achieve a virtuous circle of cooling the condenser while maintaining gas temperatures at an acceptable/appropriate level.
In addition, by using a turbo expander to expand the gas at the pressure reduction station, electricity production at the iQuadgen® Hybrid CSP plant will increase substantially, compared to the output from conventional CSP plants. In essence more electricity is produced by a smaller overall plant.
Finally, by using a renewable and sustainable source of heat, such as a sustainable bio-energy fired engine or fuel cell, to provide the gas pre-heat needed during the hours of darkness, the carbon footprint of the iQuadgen® Hybrid CSP is minimised, with the potential for yet further electricity generation.