Energy is at the heart of human civilization, and its evolutions. Fossil energies are not infinite, and foster climate change. We must become a less consuming and more responsible world; where primary energy is renewable and carbon free; where energy is produced, processed and used locally. Energy transition is indeed a revolution: intermittent renewable energy and local energy management are already here and are our future. Energy storage is the key to this future. To avoid losing intermittent energies when they are produced in a larger amount than needed. To transform electricity into storable fuel, hydrogen, and then fuel back into electricity and heat, according to the needs. That's what Sylfen is about. Sylfen is based on CEA patents. Our core technology is a reversible high temperature system working as an electrolyser and as a fuel cell. Sylfen's Smart Energy Hub is designed for sustainable buildings. It is a secured and connected energy storage solution. With the Smart Energy Hub you can store available power as hydrogen. Then use this hydrogen back to cover your power and heat needs, or sell back to the local smart grid. If the hydrogen tanks are empty, do not worry: the Smart Energy Hub will produce power and heat from natural gas or biogas. And if you want to drive with home made clean fuel, just use part of the hydrogen for your fuel cell car! We believe that science and technology can change the world. Sylfen is turning science and technology into reliable products, to sustain a profitable and responsible business worldwide.