Sekyere C.K.K.,Kumasi Polytechnic |
Forson F.K.,KNUST |
Renewable Energy | Year: 2016
A mixed mode natural convection solar crop dryer with a backup heater was designed and constructed from locally available materials and used to dry freshly prepared pineapples under four drying Scenarios for drying to correspond to specified drying periods for four typical seasons in Ghana. The experiments were devised for the material moisture content to be monitored continuously till the desired moisture content of between +106% and 184% (d.b) was achieved. In solar heating mode of operation, results show that the thermal mass was capable of storing part of the absorbed solar energy but the quantities involved are insufficient to sustain night drying. It was possible to dry a batch of pineapples in each mode of operation. The dryer reduced the moisture content of pineapple slices from about; 924% to 106% in 19 h; 1049% to 184% in 10 h; 912% to 155% in 7 h; and 1049% to 144% (d.b) in 23 h, for drying in Scenarios 1, 2, 3 and 4, respectively. The average moisture pickup efficiency values obtained were 27%, 24%, 11%, and 32% for drying in Scenarios 1, 2, 3, and 4, respectively. © 2016 Elsevier Ltd.
Kemausuor F.,KNUST |
Kamp A.,Technical University of Denmark |
Thomsen S.T.,Technical University of Denmark |
Bensah E.C.,Kumasi Polytechnic |
Stergard H.,Technical University of Denmark
Resources, Conservation and Recycling | Year: 2014
Biomass is an important renewable energy source that holds large potential as feedstock for the production of different energy carriers in a context of sustainable development, peak oil and climate change. In developing countries, biomass already supplies the bulk of energy services and future use is expected to increase with more efficient applications, such as the production of biogas and liquid biofuels for cooking, transportation and the generation of power. The aim of this study is to establish the amount of Ghana's energy demand that can be satisfied by using the country's crop residues, animal manure, logging residues and municipal waste. The study finds that the technical potential of bioenergy from these sources is 96 PJ in 2700 Mm3 of biogas or 52 PJ in 2300 ML of cellulosic ethanol. The biogas potential is sufficient to replace more than a quarter of Ghana's present woodfuel use. If instead converted to cellulosic ethanol, the estimated potential is seven times the estimated 336 ML of biofuels needed to achieve the projected 10% biofuels blends at the national level in 2020. Utilizing the calculated potentials involves a large challenge in terms of infrastructure requirements, quantified to hundreds of thousands of small-scale plants. © 2014 Elsevier B.V.
Adjei P.O.-W.,KNUST |
Agyei F.K.,Forestry Research Institute of Ghana
Environment, Development and Sustainability | Year: 2015
Well-being, a condition of positive physical, social and mental state of life, has become a prime focus of research in recent years as people seek to achieve and sustain it. Interacting with the natural environment has been established as a way of acquiring well-being benefits. However, the extent to which well-being depends on various aspects of the environment particularly biodiversity has received less attention. This paper examines the relationship between the level of biodiversity in an environment and human well-being. The depression and happiness scale was employed to sample 236 visitors of eight green spaces in Anglesey and Gwynedd, North Wales, while also noting socio-demographic and environmental factors such as perceived naturalness, density of visitors and noise level to establish the relationship. In each green space, the levels of native and introduced plant diversity were estimated. The paper established that level of ecological diversity determines level of people’s wellness and happiness derived from a green environment. Visitors to green spaces with higher plant diversity receive higher levels of happiness. Significantly too, diversity of introduced species was a better predictor than native plant diversity. Perceived naturalness, density of visitors and visitors’ age was also predictors of happiness. It is concluded that increasing the level of biodiversity in an environment could improve people’s well-being. However, the finding about introduced versus native species deserves more attention. © 2014, Springer Science+Business Media Dordrecht.
Aabeyir R.,WASCAL Graduate Research Programme |
Adu-Bredu S.,Forestry Research Institute of Ghana |
Agyare W.A.,KNUST |
Weir M.J.C.,University of Twente
Energy for Sustainable Development | Year: 2016
The impacts of charcoal production on woodland were assessed in the Forest-Savannah Transition Zone of Ghana to facilitate policy formulation for a win-win situation for both sustainable woodland management and charcoal production. Twenty-three harvested sites in two charcoal producing communities were assessed in terms of the extent of harvested sites, changes in biomass carbon stock and tree basal area. The boundary of each site earmarked for charcoal production was mapped with a hand-held Global Positioning System, and the diameters at breast height (dbh) and the heights of trees of dbh ≥ 5 cm were measured, prior to harvest. The extent of harvested sites was compared with the Intergovernmental Panel on Climate Change criterion of "devegetation" using Wilcoxon test, while the biomass carbon and basal area of the harvested trees were compared with those of the remnant trees using Mann Whitney t-test. The median of the extent of harvested sites (M = 0.23 ha, P = 1.00) was significantly higher than 0.05 ha, the Intergovernmental Panel on Climate Change minimum criterion for "devegetation", while the difference between median basal area of harvested and remnant trees was significantly greater than zero (Gh - Gr = 2.6 m2 ha-1; P = 0.001) at 95% significant level. The Mann Whitney test also provided sufficient evidence (n = 23; Mhc - Mrc = 12.07 t ha-1; P < 0.001) against the null hypothesis that the difference between the medians of the aboveground biomass carbon in the harvested and remnant is zero at 95% significant level. On the basis of the IPCC definition of "devegetation" and the changes in basal area, it suggests that intensive charcoal production has the potential of degrading woodlands. Nonetheless, it is worth highlighting that, none of the harvested sites had zero basal area or biomass carbon after harvest, which is a significant revelation for sustainable woodland management for charcoal production. The study further revealed that the extent of harvested site is not an appropriate measure of the impact of charcoal production on woodland since it does not account for the number and sizes of the trees harvested. Therefore, the impact of charcoal production on woodland may not be as alarming as it is generally perceived when the extent of harvested site is used as a measure. The impact of charcoal production is often over-generalized and that, "devegetation" of harvested sites is an issue of post-harvest woodland management and not the impact of charcoal production per se. Therefore, the evidence of the impact of charcoal production on woodlands shown in this study should be basis for sustainable woodlands management and not basis for halting charcoal production in the study area. © 2016 International Energy Initiative.
Serwaa Mensah G.,Kwame Nkrumah University Of Science And Technology |
Kemausuor F.,KNUST |
Brew-Hammond A.,Kwame Nkrumah University Of Science And Technology
Renewable and Sustainable Energy Reviews | Year: 2014
Providing access to modern energy services for development is a daunting task which requires rigorous planning based on robust information. Energy access indicators enable measurement and monitoring of the progress of energy access expansion efforts, thus informing corrective efforts and efforts worth replicating. This paper reviews what has been proposed to constitute energy access and energy access indicators. The paper further reviews briefly the different types of energy access indicators and analyses access to modern energy in Ghana as measured using the energy access indicators employed in Ghana. The paper concludes that Ghana has achieved commendable access to modern energy services compared to her sub-Saharan peers but recommends further efforts to achieve the set targets of universal access to electricity by 2020 and 50% access to LPG by 2020. The paper finally recommends further work on the different types of indicators which are relevant for tracking energy access progress but are not currently employed in the country. © 2013 Elsevier Ltd. All rights reserved.