- High efficiency: means that very little energy is being converted to heat. Tigo's efficiency is ~99.5%, on a 250W module it means only 0.5% is being dissipated, and in this example 1.25W. For Tigo's Smart Jbox under standard conditions this means +12C to the ambient temperature. If the ambient is 50C, Jbox close environment will become 62C. The Optimizers maintain high efficiency throughout the entire operation range, and even at rated current it brings the temperature up only by ~30C. Compared to other PV modules power electronics this is a low number. Microinverters for example dissipate at standard operation ~12W (for us 1-1.5W!).
- The optimizer (even Smart Jbox) is physically separated from the panel backsheet, and the additional heat is not dissipated directly into the PV module. There is a gap between the Jbox plastic and the PV module back-sheet, allowing airflow to cool down the optimizer and module. See pictures, optimizer on cool and hot backsheets, and a micro inverter for comparison. You can show that in both cases, even with the heat dissipation the optimizer maintains a temperature which is cooler than the backsheet temperature.
Tigo Optimizer on a hot backsheet
Tigo Optimizer on a cool backsheet