Prospects of Bioenergy Production for Sustainable Rural Development in Ghana

Biomass supplies about 80% of the energy needs for cooking and heating in rural Ghana. It is predominantly used in traditional and inefficient forms (firewood and charcoal), which presents environmental and health concerns. In order to better the living standard in rural Ghana, efforts must be made to provide modern energy services. Most rural communities in Ghana are so remote that an extension of the national grid is uneconomical, hence biomass electricity provides a viable alternative. Biomass is pivotal to the socio-economic development of rural Ghana due to its easy accessibility and enormous potential in the production of varied energy forms. In this paper, a comprehensive review of biomass resources, biomass energy conversion technologies and bioenergy production potential for rural development in Ghana is provided. The most important feedstock from an energy perspective was found to be crop residues. Based on 2017 statistics, Ghana has a theoretical potential of 623.84 PJ of energy from agricultural crop residues and 64.27 PJ of energy from livestock production. Evidence from literature suggests that biomass gasification is the best conversion technology to expand electricity access rate for rural households in Ghana. The paper concludes that although ample biomass resources exist, cocoa pod husks (CPH) which is very common in rural Ghana can be pelletized and used as feedstock for rural power generation systems.

Evaluation of model predictive control(MPC)of solar thermal heating system with thermal energy storage for buildings with highly variable occupancy levels

The presence or absence of occupants in a building has a direct effect on its energy use,as it influences the operation of various building energy systems.Buildings with high occupancy variability,such as universities,where fluctuations occur throughout the day and across the year,can pose challenges in developing control strategies that aim to balance comfort and energy efficiency.This situation becomes even more complex when such buildings are integrated with renewable energy technologies,due to the inherently intermittent nature of these energy source.To promote widespread integration of renewable energy sources in such buildings,the adoption of advanced control strategies such as model predictive control(MPC)is imperative.However,the variable nature of occupancy patterns must be considered in its design.In response to this,the present study evaluates a price responsive MPC strategy for a solar thermal heating system integrated with thermal energy storage(TES)for buildings with high occupancy variability.The coupled system supplies the building heating through a low temperature underfloor heating system.A case study University building in Nottingham,UK was employed for evaluating the feasibility of the proposed heating system controlled by MPC strategy.The MPC controller aims to optimize the solar heating system’s operation by dynamically adjusting to forecasted weather,occupancy,and solar availability,balancing indoor comfort with energy efficiency.By effectively integrating with thermal energy storage,it maximizes solar energy utilization,reducing reliance on non-renewable sources and ultimately lowering energy costs.The developed model has undergone verification and validation process,utilizing both numerical simulations and experimental data.The result shows that the solar hot water system provided 63%heating energy in total for the case study classroom and saved more than half of the electricity cost compared with that of the original building heating system.The electricity cost saving has been confirmed resulting from the energy shifting from high price periods to medium to low price periods through both active and passive heating energy storages.