Introduction: Introducing a voltage reduction system into incoming supplies is common practice for office and industrial installations and large savings in energy consumption are claimed.

This pilot is to install an EMS Powerstar Voltage Optimiser on one of the incoming LVAC supplies at Rayleigh substation and to carry out an evaluation of the benefits and any deployment issues over a period of 1 year.

There are 2 proposed options with different potential benefits:

• 1 x 500kVA unit on one transformer, cost £27.5k inc. installation

• 2 x 500kVA units, 1 on each transformer, cost £54.75k. Inc. Installation.

This solution has already been described in a Strategy Brief and the pilot installation at Rayleigh has been supported in principle at EEPIG in April 2011.

Objectives: This Project is to pilot the installation of a Voltage Optimiser at Rayleigh substation. This is to evaluate the claimed benefits of energy savings on electricity consumption by reducing the incoming LVAC supply voltage by a fixed amount into the site LVAC board. There are also additional benefits which are due the reduced heating and insulation stresses on the substation connected equipment, which should improve asset life and reliability.