The heat wave that swept through Brazil earlier this month pushed the country's energy consumption to record levels, raising questions about how the heat will affect the growing share of solar power systems.

Caetano Mancini, head of marketing and communications solutions strategy at Tempo OK, a Brazilian weather data provider, estimates that, given the heating effect of photovoltaic systems, efficiency losses during the last heatwave could reach 15%.

The ideal operating temperature of solar panels is about 25 C. At least that's the case with industry testing and evaluation standards. On average, when the panel temperature exceeds 25 degrees Celsius, the efficiency of the photovoltaic system decreases by 0.4 percent for every degree [Celsius] increase.

Despite the loss of efficiency caused by high temperatures, the popularity of solar power in meeting load demand is still increasing, because photovoltaic power generation coincides with the peak demand associated with high temperatures.