Maximum power point tracking charge controllers for telecom applications-analysis and economics

Simple charge controllers connect photovoltaic modules directly to the battery bank resulting in a significant power loss if the battery bank voltage differs greatly from the PV Maximum Power Point (MPP) voltage. Modeling work at AES has shown that DC-DC converter type MPP tracking charge controllers can deliver more than 30% more energy from PV modules to the battery when the PV modules are cool and the battery state of charge is low-this is typically both the worst case condition (i. e. , winter) and also the design condition that determines the PV array size. Economic modeling, based on typical telecom system installed costs shows benefits of more than 3/Wp for MPPT over conventional charge controllers in this application-a value that greatly exceeds the additional cost of the DC-DC converter.