Objectives of the service
The integration of concentrating solar thermal power plants into the electricity grid requires both day-ahead and intra-day forecasting of the energy production. Direct solar irradiance forecasting is needed together with temperature and wind speed forecasts.
In the Spanish region of Andalucía, at the foot of the Sierra Nevada Mountains, Solar Millennium AG has developed the first parabolic trough power plant in Europe, Andasol 1. With a collector area of more than 510,000 m2, equal to more than 70 soccer fields, Andasol is as of 2010 the world's largest solar power plant. It has a total capacity of 50 MW. Together with Andasol 2 and Andasol 3 it supplies up to 500,000 people with solar electricity.
The planned forecasting prototype system supporting the first pre-operational services will be integrated into the parabolic trough power plant Andasol 3. Nevertheless only one part of the prototype, the power plant model will be specialized on parabolic trough power plants. As all concentrating technologies are using direct radiation as power source, the first part of the forecasting prototype that does the prevision of the radiation would also be usable for other technologies. The second part, the power plant model, would have to be replaced to do forecasting for a power plant using another technology.
Also the legal framework that is analyzed within this study is mainly not depending on the type of technology. This means that in nearly all cases the same legal framework can be used by parabolic trough technology as well as by the other concentrating technologies.
Users and their needs
Solar-thermal projects are large scale and complex projects. Therefore three different end users have to be taken into account for the FoSyS forecasting system and their associated services:
- Owner of the power plant
- Owner of the forecasting system interested in a high quality to maximize profit
- Engineering company of the solar-power plant
- Implementation of the system
- Operator of the power plant
- User of the forecasting system
There are three use cases needing definitely such a forecasting service: one is the participation in the Spanish electricity market. The participation requires the forecasting of the production. A high quality forecasting system reduces the risk of high penalty payments due to inaccurate production forecasting. The second use case is the application for the license for the grid access. As predictable and reliable renewable energy production, CSP is preferred against other renewable power production. A forecast system will help to meet the needed requirements. Finally a forecasting system will be needed for the optimization of the power plant operation process with its different aspects of maintenance, solar field operations, operation planning and wind security shutdowns.
Service/ system concept
The CSP-FoSyS forecasting service will give a forecast of the energy production of a specific power plant. Currently, such a service is not available on the market. Therefore, CSP plants are missing the economical chances of the opportunity to take part at the day-ahead and intraday electricity markets.
Space Added Value
- Satellite communications is crucial for the service.
- The EUMETCast system is a critical component as Earth Observation information products are only valuable in if they can be provided as fast as nowadays realised in the EUMETCast.
- The use of Earth observation data includes EUMETSAT data products, MSG-based parameters and raw data. Additionally, aerosol monitoring from space is necessary for appropriate direct irradiance retrieval.
- Further use of satellite based communication is needed to integrate remote ground measurement stations in areas without telephone or mobile connection.
- Navigation satellites can be additionally used for time synchronisation of ground measurements. A correct geolocation of e.g. clouds observed by ground measurements is only possible if the time stamp is accurate.
- Satellite based communication can be used as backup communication between several parts of the CSP-FoSyS system.
This project follows the FoSyS Pre-Feasibility study. In there the presentation of CSP Technology including the market conditions was made. A scenario analysis with a first financial benefit analysis was also included. An identification of use cases and user requirements was made including a technology gap analysis. A preliminary functional concept was elaborated considering a preliminary state of the art technologies as well as a trade-off analysis was executed.
The present study follows up the analysis of the state of the art and appropriate technologies, the definition of system requirements, a viability analysis, the implementation of a prototype as well as the proof of concept for the complete system.
Currently, the system and service specifications for the prototype version of the system are finished as well as the viability analysis for the service provision. The state of the art analysis on appropriate technologies is nearly finished.
The implementation of the prototype has started as well as the proof of concept for the different subsystems.