DISCUSSION
The present work allows the selection of the most satisfying seed species and oil derivatives to use for
an electrical transformer application. Accordingly, the most promising candidates are based on refined
rapeseed oil and its derived esters. A prototype composition, without any additives, has been patented
and work is in progress to achieve a more complete characterization and validation of such formulae.
The investigations are carried on in collaboration with transformer manufacturers, seed producers and
oleochemist partners.
The preliminary results definitely demonstrate the ability of these alternative liquids to fulfil the key
characteristics for use in transformers. In particular, all the requirements for unused synthetic organic
esters are fulfilled by these first formulations. A summary of the results is shown in Table III
regarding the properties of existing dielectric liquids.
Table III : Comparison of Transformer Dielectric Fluids – Typical Values