To make hydrogen a feasible energy carrier, its transformation into another chemical is advisible. Formic acid may constitute an attractive option to store hydrogen in a dense and safe form. The efficiency of formic-acid-based process chains for the storage of hydrogen energy has been evaluated. The efficiency is highly dependent upon the way formic acid is produced. Options based on reactions of hydrogen with carbon dioxide show a rather poor energetic performance, while routes using renewable production of intermediate carbon monoxide can reach competitive efficiencies. For the storage of electrical energy, an overall efficiency of about 12% is possible using the current state of the art technology, but alternative processes show potential for higher efficiencies.