Siemens Power Transmission and Distribution (PTD) has been awarded an order by Italian energy group HERA (Holding Energia Risorse Ambiente), Bologna, for the delivery of high-voltage and medium-voltage switchgear and the associated measurement, control and protection technology for eight new power plants. HERA, the first Italian multi-utility and one of the European market leaders in the service sector for power and water supply and environmental technology is currently constructing three of eight planned power plants in the Emilia Romagna region for the combined generation of power and heat from waste. The power plants under construction are in the cities of Ferrara, Forli and soon in the city of Imola. Delivery of the first switchgear bays for the power plant in Ferrara is planned for January 2007. The last of the switchgears to be supplied by Siemens for the power plant project is scheduled to go into operation in 2009.
As part of this project Siemens is delivering seven gas-insulated high-voltage switchgears for 132 kV, an air-insulated high-voltage switchgear for 132 kV as well as 15 kV medium-voltage switchgears and other medium-voltage switchgears for the emergency supply from the local distribution system, protection and control system, protection relays and power transformers.
The order also includes supervision of assembly as well as commissioning. For the largest and most complex of the eight planned power plants, the plant in Imola, an innovativ protection and control system concept developed by Siemens in cooperation with HERA will also be implemented using Siemens technology. This protection and control system offers three options for continued operation under difficult network conditions and in the event of faults in the high-voltage system that do not in themselves result in isolation of the generator group.
• Isolated operation is maintained, provided that the system disturbance allows this. The communal distribution system is decoupled from the national transmission network and the supply is only maintained for critical users.
• If operation in this way is not possible because of the extent and duration of the network disturbance, the system maintains the power plant’s own requirement as a minimum to be able to supply municipal users again as quickly as possible.
• Should the supply of the power plant’s own requirement also fail, the system enables the plant to be restarted. If serious problems occur in the national grid, for example a blackout, the Siemens system can ensure the power supply to a large number of municipal users. In this way, the protection and control system supports a national power restoral plan which prefers independently operated islands that can be connected quickly to the national transmission network.
In addition to this order Siemens also received an order for the assembly and maintenance work for all switchgears and for the supply of spare parts for a period of 12 years.