High Combi: HIGH solar fraction heating and cooling systems with COMBInation of innovative components and methods, is a EC co-founded project wich aims at developing high solar fraction systems by an innovative combination of optimized solar heating, cooling and storage technologies. Demonstration plants will be constructed (Greece, Italy Austria and Spain) using different technologies, components and control strategies for achieve high solar fractions values. Innovative techniques, components and/or configurations will be examined (new storages, use of rejected heat during cooling, combined heating and cooling control). Demonstration plants' monitoring data will be analysed, the simulation and design tools validated and the plants performance evaluated. Market analysis will be carried out in order to estimate the potential penetration af these systems in the european heating and cooling market.
The sectors of the implementation are all medium and large buildings end-users having heating and cooling loads along the year.
Objectives
- Combine the two tecnologies of solar combisystem and solar cooling system with innovative seasonal storage device that can reach a Solar Fraction approching 100%.
- Develop high solar fraction systems by an innovative combination of optimized solar heating, cooling and storage technologies evaluating different configurations optimized by dynamic simulation.
- Realize demonstration plants using different combination of technologies, components and control strategies.
Abstract
The proposed project is based on two technologies: Solar combisystems and solar cooling systems. Solar combisystems are solar thermal systems that provide not only hot water but also space heating. Few multi-family house with Solar combisystem plant have been realized but they cover quite low solar fractions in the order of magnitude of 10%. In larger applications, e.g. multi-family houses, most solar thermal systems supply only domestic hot water because a larger collector areas, that are necessary for higher solar fractions, cause problems during stagnation in summer. The proposed project will solve this problem by using the surplus energy for cooling. The solar thermal collector area and storage can be dimensioned large enough to cover a high solar fraction of heating load; the same collector area can be used to supply heat to a cooling machine in summer. The key component of the system is the storage device. The approach suggested in the proposed project is to use Boreholes around the tank for add substantial volume to the whole storage. Will be used also a low-temperature heat distribution system for use the heat at a wider range of temperatures, on the other hand, the use of higer temperatures for the cold distribution systems (18°C compared with the 12°c for conventional systems) will allow the driving temperature of solar cooling machines to be as low as possible, thus increasing the efficiency of the solar collectors. Then will be evaluated different high solar fraction configuration using dynamic simulation. Will be find the best control strategy for each plant, so will be realized and monitored four demo plants in Greece, Austria, Italy and Spain. A software tool will be developed and tanks to the symulation campaign it will be performed and validated. At the end of the project will be also available a market analysis for the Highcombi project and its potential in several european country evaluating also specific end users.