Combustion Engine vs Gas Turbine: Derating due to Ambient Temperature
The increasing need for flexible power across the world, often in harsh climates, makes power plant performance under varying conditions an important consideration in technology selection. As combustion engines are less sensible to temperature and humidity, Wärtsilä power plants outperform gas turbines in hot conditions.
Depending on the technology and site conditions, a power plant’s actual electrical output, efficiency, and fuel consumption can be quite different than its performance at design conditions. Ambient conditions can vary dramatically with geographic location and by season. For example, summer temperatures in the Middle East and northern Africa frequently exceed 40°C (104°F), while large seasonal temperature swings of over 38°C (100°F) occur in some locations. As surging temperatures usually correspond to peak electrical demand, reduction in power output at high ambient temperatures can be problematic. Gas turbines in particular can experience significant performance derating in hot, humid conditions.