As the amount of data centers continues to increase, their electricity consumption and emissions are being reviewed. The current backup solution is a conventional diesel generator running on fossil fuels. As part of climate goals to reduce carbon emissions, renewable energy sources like fuel cells running on hydrogen are being considered. The following degree project aims to analyse the impact of replacing a fossil-powered backup power system with fuel cells as well as providing insights into which parameters affect the economic analysis the most. Current studies, reports and websites were used to gather a better understanding of fuel cell systems and their key components. The calculations were carried out using values obtained from literature which then were used for simulations in Excel. The results indicated a net profit for the proposed fuel cell system during the expected lifetime. A proton exchange membrane fuel cell (PEMFC) functions very similarly to a diesel generator while reducing emissions. While the operating costs for the conceptual FC system are lower, the initial investment is much more expensive compared to the diesel system. Even though the economic investment yields a negative profit, large carbon dioxide savings are made. To give a better understanding of how different aspects impact the economics a sensitivity analysis was also carried out. While the current results show that the investment is not feasible, many of the parameters analysed in the sensitivity analysis indicate a more hopeful future forecast.