This study aimed at evaluating the potential biogas production from four main sources, in terms of the volume of methane for energy production and the equivalent avoidable carbon dioxide emissions in 2020 through to 2030. It was based on the projection of methane production from common livestock and poultry manure, possible landfills, wastewater treatment plants, and palm oil mill effluent. This paper uses sound and reliable methodology to estimate the biogas potential of these major resources, which could lead to significant achievement in environmental sustainability via biogas generation and carbon dioxide emission reduction. The results showed that a total of 690.7 million m³ and 848.74 7 million m³ of methane could be obtained from all the sources considered in 2020 and in 2030, respectively, which translates to about 1.84 TWh_el and 2.28 TWh_el. It also meant that a total carbon dioxide equivalent emission of 12.36 million tCO₂-eq and 15.82 million tCO₂-eq could be avoided in 2020 and 2030, respectively. The results of this study therefore, show the remarkable contribution that biogas technology can make, as well as serve as an immediate technical information for policies makers, government agencies, and potential investors on the development of biogas technology in Ghana. Significant achievements can be made when comprehensive attempts are made so as to provide sustainable energy by integrating and improving livestock rearing, application of comprehensive solid and liquid waste management system and usage of best practices for managing agro-processing residues, which are integral part of the socio-economic activities in Ghana.

Aquatic invasive weeds affect hydrological, ecological, and socio-economic activities on freshwater ecosystems. On the Lower Volta River (LVR) of Ghana, invasive aquatic weeds have been known to be nuisance to fishing, navigation, aquaculture, hydropower production and other agricultural practices in the area. While information on the spatial and temporal distribution of aquatic weeds would be beneficial in improving weed management and control measures on the river, such information is very scanty. Also, these aquatic weeds are also biomass resources, that can be transformed to bioenergy. Thus, this study evaluated the spatial and temporal variations of aquatic weeds on the Lower Volta River, and assessed their potential biomass for bioenergy production.

Lignocellulosic residues, such as straw, are currently considered as candidates for biogas production. Therefore, straw fermentations were performed to quantitatively estimate methane yields and cell counts, as well as to qualitatively determine the microbiome. Six fully automated, continuously stirred biogas reactors were used: three mesophilic (41 °C) and three thermophilic (58 °C). They were fed every 8 h with milled wheat straw suspension in a defined, buffered salt solution, called ‘synthetic manure’. Total reflection X-ray fluorescence spectrometry analyses showed nickel and tungsten deficiency in the straw suspension. Supplementation of nickel and subsequently tungsten, or with an increasing combined dosage of both elements, resulted in a final concentration of approximately 0.1 mg/L active, dissolved tungsten ions, which caused an increase of the specific methane production, up to 63% under mesophilic and 31% under thermophilic conditions. That is the same optimal range for pure cultures of methanogens or bacteria found in literature. A simultaneous decrease of volatile fatty acids occurred. The Ni/W effect occurred with all three organic loading rates, being 4.5, 7.5, and 9.0 g volatile solids per litre and day, with a concomitant hydraulic retention time of 18, 10, or 8 days, respectively. A maximum specific methane production of 0.254 m³ CH₄, under standard temperature and pressure per kg volatile solids (almost 90% degradation), was obtained. After the final supplementation of tungsten, the cell counts of methanogens increased by 300%, while the total microbial cell counts increased by only 3–62%. The mesophilic methanogenic microflora was shifted from the acetotrophic Methanosaeta to the hydrogenotrophic Methanoculleus (85%) by tungsten, whereas the H₂-CO₂-converter, Methanothermobacter, always dominated in the thermophilic fermenters.