HCNG (or H2CNG) is a mixture of compressed natural gas and 4-9 percent hydrogen by energy.^[1] It is used as a fuel gas for internal combustion engines^[2] and home appliances. Hydrogen contents of less than 50% in the HCNG blend have leakage and flammability risks similar to those of CNG alone^{[citation needed]}. With the hydrogen being part of the mixture, there are no special precautions needed to avoid hydrogen embrittlement of the materials coming in contact with the mixture.^[3] HCNG dispensers can be found at Hynor (Norway) Thousand palms and Barstow California^[4] Fort Collins Colorado, Dunkerque, Grenoble and Toulouse (France)^[5] Goteborg Sweden, Dwarka and Faridabad^[6] (Delhi), India ^[7] and the BC hydrogen highway in Canada.

HCNG for mobile use is premixed at the hydrogen station.

Contents 1 Research 2 Codes and Standards 3 See also 4 References 5 External links

[edit] Research

Testing is underway in Ameland for a 3 year field testing until 2010 were 20 % hydrogen is added to the local CNG distribution net, the appliances involved are kitchen stoves condensing boilers and micro-CHP boilers^[8][9]. To get the most out of a ICE in transportation if higher levels of hydrogen are added modifications have to be made in the corresponding engine and the control strategy^[10][11][12].

[edit] Codes and Standards

The National Fire Protection Association 52 presently covers CNG and hydrogen fueling stations. Blends with < 20% hydrogen by volume are treated identically to CNG^[13]

[edit] See also

• HCNG dispenser
• Hydrogen infrastructure
• Hydrogen economy

[edit] References

[edit] External links

• EERE - hydrogen blends