Gas turbine evaporative cooling evaluation for Lagos – Nigeria

• The paper models the performance improvement of GTs with evaporative cooling.
• Economic impact evaluation of evaporative cooling is applied to a GTGE 9E.
• A practical limit for the width of the cooling potential interval is given.
• CAPEX at which evap. cooling results in increased electricity income is shown.
• GTs fitted with evaporative cooling have better performance.

Evaporative cooling is widely recognised as one of the available gas turbine power augmentation tools. Due to its inherent characteristics evaporative cooling is thought as being only effective in geographic areas with high ambient air dry bulb temperature and low relative humidity. This paper clarifies, via literature review and thermal modelling examples, the fact that there is still potential for evaporative cooling in high temperature and relative humidity areas. The paper also estimates the maximum cost of the evaporative cooling installation that will yield a positive return of investment to plant owners in the decision of retrofitting evaporative cooling systems for the particular location of Lagos in Nigeria. In consequence power plant operators, especially those whose power generation assets are located on coastal environments, should be aware of the prospective benefits associated with such cooling technology.