Bendtsen, C. and Bilde, N. (2020)
Christoffer Bendtsen; Nicklas Bilde
About the publication
There is a need for innovative solutions to the challenge of clean cooking, and to enable adoption of renewable energy by households in developing countries. In low-income countries such as Kenya, residents in informal settlements and refugee camps cook using 'dirty’ fuels such as kerosene, charcoal and firewood, which causes CO2-emissions, deforestation by collection of firewood, and bad indoor air climate, which causes the death of 3,000,000 people yearly. Existing solutions show great potential in enabling cooking with clean energy but prices and low affordability of electric battery storage technology are still limiting the wider adoption amongst the world’s poorest. Thermochemical energy storage (TCES) shows great potential in solving the stated problems for clean cooking.
This report focuses on TCES using salt hydration for storage of solar energy for time-shifted cooking and reaction initiation by hydration using liquid water. Various salts are considered for the application and from evaluation of properties and fit with context, two kinds of salts have been found best fit for utilising in a clean cooking salt hydration application. Through two test iterations with prototype rigs various parameters of both hydration and dehydration have been tested. Results show that salt hydration do have potential as a means of energy storage technology to be used for clean cooking solutions if certain parameters can be optimised. Main conclusions are that the dehydration process is too slow, conversion rates need to be examined, and heat transfer to the pot needs improvement. In this project, proposed solutions include addition of chemical additives, structuring the salt, addition of a heat transfer element and different dehydration measures.