The Influence of Climate Variability and Change on the Attainment of Energy Security in Ghana: A Study of the Akosombo Hydroelectric Power Project

Abstract

ABSTRACT The impacts of climate variability and change including the influence of ENSO are real and affect several productive economic sectors such as agriculture, water, forest resources and energy. Energy is a very important sector for achieving sustainable development. Ghana has continuously relied heavily on Akosombo and Kpong hydropower stations to supply electricity for household and industrial use. Historical records have shown that variability and change in rainfall including the influence of ENSO has affected lake water levels and consequently the amount of power generated by these hydropower projects. This led to power crises and periodic blackouts in 1984, 1998, 2003, and 2007. The current power crisis has been ongoing for the past three years. This study therefore sought to assess the likely effect climate variability and change will have on Ghana’s energy security since many projections for the country point to a warmer dry future. This study used regression analysis, F-test and t-test to analyze the influence of rainfall, ENSO, lake level elevation and net lake inflow on power generation at the Akosombo Hydroelectric power station from 1970 to 2010. The study found that ENSO explained 19.5% of the variability in rainfall inputs into the lower Volta Basin where Ghana’s hydropower projects are found. Rainfall variability accounted for 21.2% of the year to year fluctuations in power generation from the Akosombo Hydroelectric power station between 1970 and 1991. Additionally, ENSO and lake water level accounted for 72.4% of the interannual fluctuations in power output between 1991 and 2010. The occurrence of an El Niño episode was found to reduce Akosombo power output by 1169.64GWh per year. The study therefore concludes that the country should diversify its power needs away from hydropower in order to attain energy security for current and future generations.