Photovoltaic Installations in Cold Climates

For self-contained microwave repeaters and telecommunication devices in remote and rural areas, a photovoltaic solar power installation is today an economic and viable alternative to a diesel generator set or other power source. Remotely located solar power installations are often exposed to temperature extremes from arctic cold to tropical heat. At both these extremes, the power system must be able to supply current for continuous, reliable operation of the total installation. The availability of the system should be as close as possible to 100%. To store the energy from the photovoltaic modules, a battery is required that can match the high reliability and availability of the modules. One battery type known for its high reliability in industrial applications is the pocket plate nickel cadmium battery. This battery can be exposed to temperatures as low as -50°C without damage or changes in its power output. The performance of pocket plate nickel cadmium batteries has been tested at temperature extremes in comparison with lead acid batteries. Several years of practical experience have documented that they provide full availability of service in the cold climates of Scandinavian countries. In brief, a computer-sized photovoltaic system utilizing pocket plate nickel cadmium batteries saves initial costs by utilizing a smaller-capacity battery bank and through reduced installation costs. Through the years, further savings come from battery longevity and minimal maintenance.