This year, our project coordinator, Politecnico di Milano (POLIMI) carried out simulations at its CSP (concentrated solar power) plant in Dubai to combine CSP with CO2-mixed electric cycles and a forward osmosis (FO) desalination system.
Using innovative technologies, POLIMI’s CSP plant has demonstrated high solar-electric efficiencies (around 19% on an annual basis) and very low specific thermal consumption of fresh water (around 90 kWhth/m3) when PABG2000 is used as the drawing agent. The synergy between electricity and freshwater production was effective.
In particular, if the CSP+FO solution studied in DESOLINATION is compared with the CSP+MED solution, assuming the same solar power plant and energy cycles, freshwater production is increased by over 40%.
The DESOLINATION project aims to develop an innovative desalination system combining direct osmosis and membrane distillation, using a draw-off solution. Forward osmosis means that seawater is extracted from the sea, the water is drawn through the membrane by the draw solution and the remaining minerals (brine) are rejected.
When the DESOLINATION solution is compared with a PV+RO plant, a 47% reduction in reflective surface is predicted, if the PV+RO plant produces both fresh water and electricity.
We have also carried out an experimental campaign on the coalescer* using a solution of water and PAGB2000, the aim being to obtain an expression for the separation efficiency, which will then be used in simulations.
*Coalescer: used to separate elements from an emulsion (i.e. liquid water and oil from compressed air using a coalescing effect)