Higher share of variable output renewables
ASTERIx-CAESar approach guarantees 24/7 RES coverage by offering storage capacity and thus provide grid stability. Moreover, the concept improves performance regarding start-ups, shut-down and load variations.Producing renewable energy is often associated with photovoltaic panels and/or wind turbines. These technologies are very cost competitive but suffer from being strongly weather-dependent, hence not dispatchable and unable to provide grid stability and reliability. In contrast, ASTERIx-CAESar offers the following approach:
- Significant increment in storage capacity of the energy system, which is mandatory to attain higher shares of the variable output renewables.
- The transition to renewable energy cannot focus on electricity only but it must cover the whole energy system – power and heat. On that account, ASTERIx-CAESar enables easy integration with industrial process heat supply and desalination. The combination with desalination is of particularly high interest, as ideal locations of CSP plants are typically in areas with low water availability.
- The ASTERIx-CAESar approach further provides grid stability by guaranteeing 24/7 renewable energy coverage of the electricity demand, both for main-grid as well as for remote off-grid areas.
- The project additionally improves response capabilities when it comes to start-up, shut-down and load variations, enabling fast start-up within several minutes (as opposed to 0.5-1h of state-of-the-art CSP plants).
- Therefore, this project has the potential to become an enabler to achieve a very high renewable energy scenario!
Higher efficiency of CSP plants
The peak solar-to-electric conversion efficiency is targeted at up to 40% (double the current state-of-the-art). This can be achieved by novel volumetric receiver approach as well as by using cheap off-peak electricity to boost conversion efficiency.The novel volumetric high-flux density receiver approach combined with smart AI-based flux map optimisation significantly reduces receiver size (i.e. costs), hence increasing concentration ratio (i.e. conversion efficiency).
By using inexpensive off-peak electricity to provide compression work for the topping Brayton cycle, the conversion efficiency of the ASTERIx-CAESar power cycle is significantly increased: the peak solar-to-electric conversion efficiency is targeted at up to 40%.
Reduced operational and maintenance costs of CSP plants
Using air instead of molten salts or synthetic oils as heat transfer fluid brings down significantly the maintenance costs and lowers various risks, too. Operational costs will be reduced thanks to AI-based heliostat control requiring less personnel on site.One of the most relevant advantages proposed in the project is to use air instead of molten salts or pressurised synthetic oils (i.e., HTF). Apart from obvious environmental and cost benefits, it also offers advantages in:
- avoiding leakage,
- eliminating corrosion,
- avoiding freezing.
Operational costs are also closely related to human resources dedicated to monitoring and operation of semi-automated control systems. Thanks to the AI-based heliostat control, the human resources need for the ASTERIx-CAESar plant operation will be significantly reduced.
ASTERIx-CAESar will contribute to two main targets:
- Short term: significant cost reduction translating into low cost of electricity (below 10c€/kWh). In spite of these efforts, CSPs will not be able to compete against PV in terms of LCOE alone. Therefore, the project suggests a new operating strategy, presenting CSP as booster for the inexpensive energy storage.
- Long term: development of the next generation CSP/STE technology with the aim to achieve additional cost reductions and to open new business opportunities.
Apart from these two objectives, the project will also explore CSP as a source of heat for industrial processes.