Scenario analysis of the electricity system of the gambia

Abstract

Sustainable Energy for All (SE4All) is an Initiative launched in 2012 by the United Nations (UN) Secretary General to achieve three interlinked objectives (i.e. ensuring universal access to modern energy services, double the global rate of improvement in energy efficiency (EE) and double the share renewable energy (RE) in the global energy mix) by year 2030. In The Gambia, the energy (electricity) supply situation is precarious and unsustainable as it currently relies on single imported fuel oil to meet the nation's demand. The dependence on the imported fuel oil cannot meet the hugely growing demand therefore resulting into huge demand-supply gap (more than 150 MW). This situation coupled with the high electricity production cost lead to the conduction of this study using Model for Energy Supply Strategy Alternatives and their General Environmental Impacts (MESSAGE). The objective of this study is geared towards exploring the optimal national electricity supply mix by employing long-term, bottom-up energy supply system optimisation tool to meet the current and future national electricity demand sustainably (i.e. considering the economic feasibility and environmental concerns). To make gains towards this objective especially diversification via increasing the renewable energy share, The Gambia, made commitments (targets) to increase centralised (grid-connected) renewable energy share in its electricity supply mix by 2020 and 2030. Based on these commitments, prompted the need to explore two possible scenarios, viz: Business As Usual (BAU) and Renewable Energy Target (RET) using Model for Energy Supply Strategy Alternatives and their General Environmental Impacts (MESSAGE) for 2030 horizon. The results showed that the system capacity development, generation as well as generation mix in both scenarios are expected to be dominated by oil (HFO/LFO) based systems up to 2019, after which the system is expected to be diversified with more of renewable energy systems at both centralised and decentralised levels and negligible contribution from alternative sources such as natural gas systems. This increase in the generation after 2019 is as result a result of the commencement of the importation of cheap hydroelectricity from the regional OMVG dams expected to come online by 2020. In addition to OMVG hydroelectricity imports is the generation from committed solar PV, wind and solar thermal projects. Generally, comparing both scenarios (BAU & RET), the RET scenario is found to be more attractive as well as attainable as a result of its increased rate of renewable energy share (by 9%), very marginal increase in total system cost (by USD $2 million), and less CO2 emissions (by 40%) and carbon intensity (by 30%) explained by more renewables (solar, wind, import hydro) penetration. However, the BAU scenario could still be attractive as Non-Annex one country, if the government considers that 10 % (2020) and 33 % (2030) renewable penetration rates suffice and not worth additional investments of USD $ 2 million. Regarding the sensitivity analysis, the BAU scenario with 5% discount rate has led to addition of more renewables energy systems and disfavours that of fossil fuel power plants while the higher discount rate of 15% favour both renewables and few fossil fuel plants and disfavouring fossil fuel generating plants.