Altitude Power Loss Calculation

Generator manufacturers use diesel engines in ISO3046 standards.

The power data of diesel engines in generator sets in kW are usually given according to1000 by height. In this article, we will give information about what kind of engine should be chosen at high altitudes and how much power loss there will be.

In general, the efficiency of all internal combustion engines decreases as they go to higher altitudes.
Regardless of the brand, all generators lose 3.5% power every 1000 feet (304.8 m.). Power loss is not calculated for the first 500 feet altitude.

For example, if your generator  set produces 100 kVA at sea level, 1853 m. Let’s calculate how many kVA will be produced in Erzurum at (6.079 ft) altitude with this formula.

6079 – 500 = 5,579.00 ft. / 1.000 =5.579 x 3.5% = 19.52%

The generator, which produces 100 kVA power at sea level, will produce 80.48 kVA power in Erzurum.

Another important point is that Turbo engines should be preferred at high altitudes. The power loss in non-turbo engines will be much greater.

Considering that most of the engines below 50 kVA power are naturally aspirated, not turbocharged, we should choose our generators for high altitude locations over generators with turbo-suction system.
In larger power generators, keeping the efficiency at the highest level is possible with motors with electronic governor. Efficiency reduction is higher in motors with mechanical governor.