Energy monitoring by satellite

The new Comalco Alumina Refinery (CAR) currently under construction near Gladstone, Queensland will feature an Australian first - a high-tech GPS-synchronised HV supervisory system which will allow the plant to optimise energy usage, trace faults and reduce energy costs.

The system will be based on Schneider Electric's STS3000 satellite time system, the first one in Australia. It is part of a significant order won by Schneider Electric, to supply both electrical equipment and expertise for the CAR project.

Bechtel Australia, engineering procurement and construction contractor for the project, chose Schneider Electric to supply HV reticulation, distribution and monitoring equipment, to develop the HV supervisory system and to investigate other means of ensuring optimum utilisation of energy.

The Schneider Electric order includes 33 kV Fluair 400NL switchgear, 6.6 kV MCset switchgear, 33 kV capacitors, 33 kV neutral earthing resistors, 110 VDC battery chargers, PowerLogic circuit monitors and Sepam protection relays.

The STS3000 will synchronise the time on the circuit monitors and protection relays throughout the plant, to an accuracy within one millisecond. Based on Schneider Electric's system manager software (SMS), the HV monitoring system will be capable of monitoring, testing and investigating supply interruptions, transients, power system quality and status of components such as circuit breakers.

Operators will be able to access this data in graphical format through the plant's computer system. If a fault occurs it will be instantly time-stamped and can be immediately traced and rectified.

The system will also allow the refinery to track how much it will be charged by its energy supplier. To provide this data, each of the plant's two separate 132 kV supplies will be monitored by a PowerLogic circuit monitor.