Wastes from tanneries present a good opportunity to produce biogas and use it in high temperature fuel cells for combined heat and power systems. Biogas is considered a renewable fuel, domestically produced and free of carbon emissions, while molten carbonate fuel cells are ultra-clean and highly efficient power generators. In this paper, we study the economic viability of a fuel cell (considerating capacities from 300kW to 1200kW) operating on biogas. The results are based on Spanish legislation, which establishes a special feed-in tariff for biogas and cogeneration. Paybacks range from 5.7 to 8.5 years depending on the fuel cell capacity. Due to the high investment and operating and maintenance cost, the Spanish feed-in tariff for cogeneration using biogas is not enough to make the project economically viable in a short-term. Further fuel cell price reducation and longer lifetime as well as new government subsidies are required