Introduction: This project will consider the use of sustainable materials for plant and the reduction of potential environmental impact on failure.

Objectives: Evaluate alternative fluids to use as an insulating fluid for transformers to determine if they can be used at voltages of interest to National Grid. Specifically to look at one synthetic ester and two natural ester materials. Particular emphasis will be placed on investigating dielectric performance at high voltages. Ideally the project will enable sufficient confidence to be gained to enable a trial of the fluid in an in service transformer