Cycled Diesel Power Plants at Newfoundland Telephone Microwave Sites

This paper reviews Newfoundland Telephone´s five year experience in the use of cycled diesel power plants as an alternative power source for prime powered microwave repeater sites. The technique has been developed from a field trial to installation at 13 remote microwave repeaters on both analog and digital heavy routes. The method capitalizes on higher fuel efficiencies yielded by diesel generators if operated intermittently at full load rather than continuously at somewhat lower loads. By coupling the concept to a network surveillance, telemetry, and control system, anticipated operational problems have been overcome. The battery plays a more dynamic role, undergoing daily discharge and recharge cycles. Replacements are more frequent, but nonetheless, the process is still economical. On average, the diesels run only 30% of the time, consuming 65% less fuel than on prime, and savings per site are on the order of $20,000 per year per site.