Poster 5: Urban Areas and Critical Infrastructure: Challenges and Opportunities for Resilient Cities
Time: 31/Aug/2016: 12:55pm-2:00pm

Safe and Decentralised Solar Hydrogen Fuel Production and Storage for Residential Building and Mobility Applications [PB 54]

Artur BRAUN1, Mmantsae DIALE2, Kelebogile MAABONG3, Rita TOTH4

1Empa. Swiss Federal Laboratories for Materials Science & Technology, Switzerland; 2University of Pretoria; 3University of Botswana; 4Empa. Swiss Federal Laboratories for Materials Science & Technology, Switzerland

Large scale facilities pose a potential risk and threat because with one isolated attack large damage can be obtained, for example in a city, potentially with a large number of human casualties.

I present a solar energy harvesting strategy which allows to generate fuel for housing and mobility in a decentralised form. A city or a part of a city cannot be shut down from energy supply by a terrorist attack on this energy generation and storage infrastructure, because it is virtually fully decentralised and independent (no electric grid).

This system is based on photo-electrochemical cell technology and takes advantage of the solar energy arriving at small landscapes in local neighbourhoods in the range of few 100 sqm area per operation unit. The fuel is hydrogen, or hydrocarbons such as methane or methanol, when carbon dioxide greenhouse gas is included in the chemical process cycle. The necessary water for the process comes from the local sewage wastewater system.

The problem of energy storage in absence of sunshine during the day is also solved by this technology, because a storable fuel is produced. The pronounced safety feature of this approach is that many small units are built, which are impossible to demolish in a terror strike, as opposed to single large industrial complexes which are very attractive for terrorists to attack because of the high destructive "efficiency" by a single plot, but also by the commensurate public attention and "terror", literally, which comes with the attack on a landmark scale facility.

The negative part in this calculation comes from the loss of efficiency by moving from few large units to many small units. This is likely the price which society has to pay for the gain in safety from terrorism.