Regional supply network paralleling applications for small and medium sized diesel generating plant

Traditionally the main use in the UK for diesel generating plant in the range 200 to 2500 kVA has been to act as standby, operating only in the event of failure of the network supply. This has resulted in relatively high capital cost equipment being, in many cases, under-utilised and neglected. Opportunities do exist for more extensive use of privately owned generation equipment and with the advent of decentralisation within the electricity supply industry, more commercial consumers are examining the possibilities of negotiating advantageous tariffs with their supply authority. Unless the consumer can either tolerate a loss of supply whilst the changeover to generator is effected, or has an uninterruptable power supply, some form of parallel operation with the network supply will be necessary. The various options available to the engineer are examined, together with the criteria necessary for safe operation, with the aid of case histories