As the paradigm of environmental awareness is considered at the same level with economic efficiency, the growing energy demand of the population has to be supplied by conscious management of the natural resources, involving sustainable energy production and energy consumption. Air pollution in urban areas carries significant risks for human health and the environment. Hydrogen is a potent candidate to ease the fossil fuel dependency of the society, in a COx-emission-free way. Though, the production, safe transportation, storage and efficient use of hydrogen have not been solved perfectly yet.
The basis for the technology development is a hydrogen storing and generating reaction system (patenting is in progress). The reaction system is suitable for the storage of hydrogen in a safe aqueous solution of formate (salt of formic acid) and the generation of hydrogen gas without the emission of carbon dioxide or other pollutants. The method bases on the hydrogenation of bicarbonate to formate followed by the breakdown of formate to bicarbonate in aqueous media. The direction (charge-discharge) of the hydrogen storage cycle can be influenced by changing the pressure.
Technology Features, Specifications and Advantages
- Safe (no explosion risk)
- Environmental friendly
- Using renewable energy sources
- Effective storage of the overproduced energy
- Cheap (formic acid costs about €0.50 / L)
Up to now we have worked in a 100 mL high pressure Parr reactor (in closed system) in which we can store 2.4 L H2 in 20mL aqueous solution. To our current knowledge approximately 1.15 kg hydrogen can be stored in 50 dm3 aqueous solution (23 kg H2/m3). In our system both the production of hydrogen (formate decomposition) and the reduction of bicarbonate was studied at 80°C but the temperature can be higher and lower, as well (60-100°C) resulting also in the change of hydrogen pressure. The only energy consuming part in the system is the heater used to achieve the corresponding temperature and the pressure-booster. Total energy demand depends on the volume of the system.
The advantage of the system is that pure hydrogen can be generated using this type of the breakdown of formate, which we can use in power generating fuel cells. The system can be an alternative solution to the safe storage and transportation of hydrogen. It can be used in mobile devices or in the large industrial energy storage sector.