DASH hydrogen storage modules are very safe hydrogen storage systems thanks to their excellent safety properties. These are unrivaled by pressure and liquid hydrogen storages:
Leakages #
The removal of hydrogen is thermally limited. As a result, in the event of a leak, not the entire stored quantity of hydrogen escapes, but only a limited leakage flow. The leakage current cools the system and causes it to move to a new state of equilibrium,the leakage rate decreases. Often, local icing will also close the leak automatically. The limitation or stop of the leakage flows means that the escaping hydrogen can be detected long before the lower explosion limit is reached. Appropriate measures can then be taken to reliably prevent the occurrence of an explosive atmosphere after detection. For more information on this dehydrogenation process, see this article.
Pressure levels #
The DASH systems operate at very low, quasi-atmospheric pressure levels, which is an important differentiation to pressurized hydrogen storage. Typically, our design engineers will choose a pressure range which is as low as the downstream hydrogen consumer, e.g., the fuel cell, allows for. As an example, if the upstream device is an electrolyzer producing hydrogen at 35 bar(a) and the downstream fuel cell consumes hydrogen at 5 bar(a), the pressure level of the storage is designed to be in the range 5-35 bar(a). Despite the relatively low pressures, the hydrogen storage density is comparable to high pressure cylinders. Low pressure levels represent a significant reduction of the risks related to pressurized systems.
Manufacturing quality #
Most of the connections in our systems are welded, which means that the entire system is permanently technically tight. At the end of production, all subcomponents undergo an integral pressure and leak test, which ensures the highest quality requirements. The systems are certified and comply with the Pressure Equipment Directive 2014/68/EU (Type 4, Module B+F). Systems certified according to other standards can also be offered on request. Thanks to the excellent safety characteristics, the DASH storage modules can even be installed and operated inside residential buildings. The fact that no ATEX zone is required around the storage modules greatly facilitates many projects.
The safety of GRZ’s hydrogen storage technology has been demonstrated in numerous successful applications. For example, GRZ’s safe hydrogen storage technology has been applied to an installation inside of a building in Bruneck, Italy. See, for example, here. An image of the plant is shown below: