Meeting electricity demand and power shortage remains as a challenge to the people of the Gambia. As the country is undergoing tremendous electricity accessibility expansion [1], to secure the environment for the future generation, it is necessary to consider renewable energy to be the major source of electricity production, to be specific, solar energy. This is because the country experiences the radiation from the sun throughout the year, it is sustainable not only to our environment for the future generations, but also economically. However, due to the intermittent nature of most renewable energy technologies, it is cumbersome to rely on them 100 % as a primary source of electricity production. Nonetheless, with suitable storage technologies, combination of different renewable sources, and intercountry grid connections can enhance to overcome this challenge. In this thesis work, designed and techno economic evaluation was carried out for high PV penetration that will meet 50 % electricity demand of the Gambia in year 2040. Three scenarios were considered in this study, based on the Strategic Electricity Roadmap 2020 to 2040 [1]. These scenarios are high, universal access (AU), and low electricity demand. Economically, 50 % electricity supply to meet the demand is possible for all the three cases. Consideration was mainly put on four key figures, thus, levelized cost of electricity (LCOE), payback period (PBP), net present cost (NPC) and solar fraction (SF). To achieve 50 % SF for the high electricity demand scenario, LCOE and PBP are 0.129 $/kWh and 12 years respectively. As for AU electricity demand case, 50 % SF is achieved with 0.126 $/kWh and 10 years for LCOE and PBP respectively. For low electricity demand scenario, 0.127 $/kWh and 10 years for LCOE and PBP respectively for 50 % SF. However, the optimum design recommended by HomerPro were 45 % SF with LCOE of 0.126 $/kWh and PBP of 9 years for high electricity demand scenario. As for the AU electricity demand case, the optimum design is 48 % SF, LCOE of 0.125 $/kWh, and PBP of 9 years. In the last scenario, which is low electricity demand case, 46 % SF, 0.124 $/kWh LCOE, and 9 years PBP.