Jérôme Bonaldi gives us a straightforward explanation of how renewable energy is stored by producing hydrogen and injecting it into the mains gas supply system. This is the Power-to-Gas concept that GDF SUEZ is now testing in Dunkerque with the GRHYD project. This small-scale demonstration explains the principle.

Jérôme Bonaldi introduces the subject of energy storage by setting the scene: it's a weekend in June; the weather is good, it's warm, there's a light wind and the wind parks and photovoltaic plants are running at full capacity. But over this long summer weekend, factories are only ticking over and household energy consumption is low. The result is that a very large amount of power is being generated and made available in the distribution network, but too little of it is being consumed, so what can we do with this surplus energy?

This renewable energy is quite simply lost, because we don't know how to store it. Or rather we DIDN'T know before the GRHYD project was launched to experiment with the «Power-to-Gas» concept. In simple terms, the «Power-to-Gas» principle is based on producing hydrogen by water electrolysis using kilowatt hours of power that would otherwise have been lost at times of high generation and low consumption.

After a small experiment demonstrating how hydrogen is produced by electrolysis, Jérôme Bonaldi explains the key advantage of hydrogen: it can be blended with natural gas to produce a domestic and vehicle fuel that can be stored safely and delivered via the mains natural gas supply system, just like other fuels.

In Dunkerque, the GRHYD demonstrator project is experimenting with using this process under real-life conditions to heat 200 homes in a new residential district, and to provide Hythane® fuel for a bus fleet currently running on VNG.

Jérôme Bonaldi concludes with these words: «With GRHYD, it's as if you were heating a house or powering a bus using the wind...  isn't life wonderful?»

Une innovation GDF SUEZ racontée par Jérôme Bonaldi : le projet GRHYD (in Franch only)

Jérôme Bonaldi has to introduce three innovations of the group in less than 10 minutes. Challenge succeded, With GRHYD demonstration.

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