
SMALL CONVERSION LOSSES DESERVE A PROPER CALCULATION
Power-conversion efficiency measures useful output power relative to input power. For a given output, higher efficiency reduces losses.
Those losses continue for as long as the equipment operates. Their significance depends on the load, operating hours and number of sites—not simply the difference between two headline percentages.
For illustration, a conversion stage delivering a constant 1 kW at 95% efficiency draws approximately 1.053 kW. At 96%, it draws approximately 1.042 kW. The difference is about 11 watts, or approximately 96 kWh over a year of continuous operation.
This is a simplified calculation, not a product comparison. It assumes constant output and efficiency and excludes equipment outside the conversion stage. Across a large installed base, those savings can accumulate. Whether they justify replacement depends on electricity prices, installation costs and the remaining service life of the existing equipment.
Peak efficiency does not settle that question. It describes performance at an optimized output load. Annual input energy consumption depends on the real output load over time and conversion efficiency under the corresponding electrical conditions. Texas Instruments’ measurement guidance illustrates why input voltage and load current must be specified when evaluating power-supply efficiency.3
In a modular power conversion system, the number of operating modules and the redundancy requirement influence the load carried by each module. A comparison should represent the system the operator will deploy.