Reliable Power Supply for Remote Telecom Facilities

Abstract:
Telecom facilities in remote areas, like repeater or cellular base stations, often cannot be powered by the electric grid. It is too expensive to build a connection or it is not ready in time. Conventional Diesel generators with standby batteries are used. This is costly and requires high maintenance. In the last years a growing number of telecom facilities use a PV panel, sometimes supported by a small wind turbine as a power source and a battery as back-up. In these applications the battery has tougher requirements as in a normal stand-by use: Every day cycling, low state of charge in winter, high over charge in summer, maintenance-free design is preferable. Test results to prove the endurance in cycles of VLA batteries according to IEC 60896-11 and of VRLA batteries according to IEC 60896-2 are presented. We also present the endurance in cycles from tubular VLA and tubular GEL VRLA batteries for the special cycles in photovoltaic systems according to the standard IEC 61427. Finally we calculate the life cycle costs of OPzS, OPzV, OGi block and AGM block for a period of 20 years. It is interesting to see, that low maintenance and high service life are the important issues for amount of the life cycle cost.