AN ASSESSMENT OF WIND ENERGY POTENTIAL IN GHANA USING WAsP
Francis Akwensivie
ABSTRACT
Data on wind as a renewable energy resource in Ghana has been rather scanty or virtually unavailable until quite recently. The wind speed in most parts of the country had been assessed to be low and inadequate (1.7 and 3.1m/s) for energy applications. However these measurements were at a height of 2 m above ground level (a.g.l.) and therefore could not be used as true assessment of wind energy potential in the country but rather for meteorological and agricultural applications.
The perception of Ghana having low wind profiles is gradually changing with new and improved instrumentation and measuring heights. Recent studies by the Energy Commission and other private concerns along the coastal regions indicate that the monthly average wind speed measurement at 12 m a.g.l. varies in the range of 4.8 to 5.5 m/s.
The purpose of this study is therefore to develop adequate, accurate and reliable wind energy data and evaluation tools as an integral part of Ghana’s energy planning and policy framework.
The study involved the extrapolation of the measured 2 m mast data to 12 m using different extrapolation techniques. The extrapolated data were then compared to measured 12 m mast data at the same site. This helped to determine the accuracies of the extrapolation techniques used. The best technique was then chosen for the extrapolation of measured 2 m mast at other locations across the country.
The WAsP PC-programe, which consists of five main calculation blocks and contains several models, was then used extensively for the analysis and generation of standardized formats. First a statistical summary of the observed, site-specific wind climate was generated from the time-series of wind measurements.
The analysed wind data sets were converted into wind atlas data sets with respect to site-specific conditions. These ‘cleaned; wind atlas data sets calculated by WAsP were then used to estimate the wind climate at other specific points when the descriptions of the terrain around these predicted sites were specified. This resulted in the generation of a wind atlas for that area.
This procedure was replicated for other measuring stations across the country to generate a wind atlas for Ghana thereby providing a new assessment of the wind energy potential.
CORRESPONDENCE
Prof Abeeku Brew-Hammond
Head
Department of Mechanical Engineering
KNUST, Kumasi, Ghana.
Phone... +233 51 60232, +233 24 410549
Fax…...+233 51 60232
AUTHORS
- Prof Abeeku Brew-Hammond
Associate Professor/Head
Department of Mechanical Engineering
KNUST, Kumasi, Ghana.
- Prof Fred Ohene Akuffo
Associate Professor
Department of Mechanical Engineering
KNUST, Kumasi, Ghana.
- Dr Jerome Antonio
Senior Lecturer
Department of Mechanical Engineering
KNUST, Kumasi, Ghana.
- Mr Francis Akwensivie
Teaching/Research Assistant
Department of Mechanical Engineering
KNUST, Kumasi, Ghana.
BRIEF CURRICULUM VITAE
Prof Abeeku Brew-Hammond is Associate Professor and Head of the Department of Mechanical Engineering at the Kwame Nkrumah University of Science and Technology, Kumasi, Ghana. He was a member of the External Review Panel for the World Bank’s donor funded energy programs and he has recently concluded an assignment as Lead Energy Expert and Team Leader for the review of UNDP and UNIDO’s Multi-Functional Platforms Program in West Africa. He has an MEng degree from McGill University, Canada, and a DPhil from Sussex University, United Kingdom.
Prof Fred Ohene Akuffo is Associate Professor and Past Dean of the School of Engineering at the Kwame Nkrumah University of Science and Technology, Kumasi, Ghana. He has undertaken several Policy Research and Consultancy Assignments for international organisations and is a member of the Energy Commission. His areas of research include Thermodynamics, Renewable Energy and Energy Policy. Prof Akuffo has an AB from Harvard University, United States and a PhD from University of Toronto, Canada.
Dr Jerome Antonio is a Senior Lecturer of the Department of Mechanical Engineering at the Kwame Nkrumah University of Science and Technology, Kumasi, Ghana. He is also the Coordinator of the Tertiary Education Project. His areas of research include Applied Mechanics and Science and Technology Policy. Dr J Antonio has a DIC and a PhD from Imperial College, United Kingdom.
Mr Francis Akwensivie is a Teaching/Research Assistant of the Department of Mechanical Engineering at the Kwame Nkrumah University of Science and Technology, Kumasi, Ghana. He is a founding member of the Creative Minds Consortium. He is also the Prime Researcher and Secretary of the Solar and Wind Energy Resources Assessment of Ghana Project Team. Mr F Akwensivie has a BSc. Mechanical Engineering (First Class) from Kwame Nkrumah University of Science and Technology, Kumasi, Ghana.