  The thermal performance of locally available oils in Uganda have been
experimentally investigated to determine their suitability for heat transfer
and solar thermal energy storage. Sunflower oil and palm oil, both local
vegetable vegetable oils and Shell thermia B, commonly used in the local
industries as a heat transfer fluid were used in the study. The oils were
heated in an insulated tank until temperatures close to their smoke points were
attained and then heating was stopped; the tank temperature was recorded for 24
hours during the cooling. The second experiement involved charging the oil in a
self-circulating system without the aid of a pump. It was observed that the
vegetable oils gained heat faster than thermia B. Sunflower oil retained heat
for a longer period compared to palm oil and thermia B. The total amount energy
stored by sunflower was equally higher than palm oil while thermia B had the
least energy stored. The results show that sunflower oil is the most suitable
oil for solar thermal storage and heat transfer.
