Solar cookers, in various shapes and sizes, have been available for a long time. The SK14 is an example of a dish concentrator where the cooking pot is positioned in the focus point and the solar tracking is made manually.
Our research direction has been on including a heat storage, such that heat can be available at times without direct sunshine. The concepts are illustrated schematically below.
Established concept for direct solar cookers
Project concept 1: heat transfer to a storage. This system can be upscaled
Project concept 2: direct illumination of a storage (Scheffler reflector) and direct charging of moduar storage units (portable heat batteries)
The technical challenges with solar thermal systems are illustrated in the figure below
Technical challenges with a solar systems
Different concepts have been considered for heat collection and storage (see some slides for some pictures and the NUFU report for more details)
Heat storageThe heat storage is the key element in our work. Two methods have typically been tested:
Computational workThe work has typically included experiments (outside in the sun and inside in the laboratory) and numerical modeling, including programming of a Ray Tracer. The modeling has involved:
We have had an interdisciplinary research team, with participants also from the social sciences (at NTNU, UKZN Durban and UEM Maputo). See a presentation at a final seminar of a NORGLOBAL project: Slides