Electricity supplies to the Isles of Scilly comprise a single 33kV undersea cable from the mainland supplemented by an island based diesel generating station. There are also remote, locally controlled generators on two outer islands available for use in limited instances.

The islands provide an effective self contained microcosm of an 11kV and Low Voltage (LV) electricity distribution system that can be monitored and controlled to provide measurement of impact and capability to accommodate Distributed Generation (DG) and other low carbon initiatives.

The Isles of Scilly Council has a published goal of the islands being energy self sufficient To this end, the council is examining methods of localised generation such as waste disposal and the islander’s themselves are keen to exploit PV and wave power on and off the smaller islands. Western Power Distribution will work in conjunction with the islanders through this initiative to ensure the full support for their desire to be energy self sufficient. The community level interest in energy management was demonstrated in their 2009 'e-day' initiative which received national BBC TV coverage.

Objectives

It is proposed to establish real time monitoring on all of the distribution substations on the Isles of Scilly in such a way that the use of the generation facilities on the islands can be maximised to secure supplies to the islands. The control and management of the generation on the islands will be affected using new methods that have not been used in Western Power Distribution before.

The monitoring at the substations will be supplemented by controls where appropriate to ensure that islander’s and company initiatives associated with localised generation can be accommodated and managed in an effective way. The initial localised generation is expected to be by PV though the islander’s themselves are actively pursuing wave power and possibly waste disposal as other sources of generation. The Scillies have the highest PV solar efficiency rating in the UK and present a challenging DG demand environment on a weakly connected rural network.

The initiative will support the council’s published goal of energy self sufficiency.