HENG

Hydrogen Enriched Natural Gas Addressing Decarbonization and Energy Efficiency

Hydrogen-enriched natural gas, or HENG, is a mixture of hydrogen and natural gas. In theory, the two can be mixed in any proportion, but typically, HENG in the range of 10 per cent to 20 per cent hydrogen by volume represents the most promising near-term option. At these concentrations, HENG is generally compatible with existing natural gas transmission and distribution infrastructure, as well as end-use equipment. Moreover, codes and standards in many jurisdictions treat HENG with less than 20 per cent hydrogen as natural gas, which will facilitate its initial deployment into gas networks. Also, at these levels HENG offers important emissions and efficiency benefits, compared with natural gas.

HENG is a unique solution that addresses two dominant energy and environmental issues: decarbonization and improved energy management. As a mixture of hydrogen and natural gas, HENG widens our efforts to build a bridge to an ultra-low carbon world. Yet introducing hydrogen into natural gas can also be seen as going “back to the future.” For more than a century, we relied on 10 per cent to 50 per cent hydrogen in manufactured gas, or “town gas,” for lighting, heating and cooking, before converting to natural gas. With HENG, it is now possible to reduce emissions, improve the efficiency of end-use equipment, and lower the overall carbon intensity of natural gas in the years to come.

HENG leverages existing pipelines and local delivery systems, and takes advantage of the growing recoverable gas reserves in North America and growing LNG supplies globally. HENG can be produced without generating carbon dioxide (CO2), using abundant and low-cost off-peak power. Furthermore the carbon from HENG production, which avoids the emissions associated with conventional carbon black production, finds uses in a variety of energy management applications. These include adsorbed natural gas storage, batteries and ultra capacitors, and cable and wires for infrastructure renewal.

From wellhead to burner tip, HENG has many potential applications and could reduce CO2 emissions in the United States by over 111 million tonnes per year. This is equivalent to the emissions from 20 million passenger vehicles or 10 million homes per year. In addition, HENG can be highly cost-competitive with many energy-related CO2-reduction strategies under consideration. On the basis of cost per tonne of CO2 abated, HENG costs less than most projections for carbon capture and storage technologies.

Experience with its use in places such as Hong Kong and Hawaii indicates that there are no insurmountable technical or safety barriers to delivering a gaseous fuel containing hydrogen and methane. The key to delivery is government policy and regulation. The following policy developments are urgently required:

• Regulatory frameworks to provide incentives and to clarify the roles and responsibilities of the gas utilities and local distribution companies;  
• Commercial incentives that level the playing field between HENG and renewable technologies, and are sufficient to allow utilities, which will own and operate HENG plants, to recover their costs;
• Consistent and clear rules for materials, system requirements, safety measures and test procedures for hydrogen in natural gas; and  
• Continued support for R&D in low-carbon technologies, and extending funding for capturing carbon from natural gas before combustion.

Applications for HENG
Combined Heat and Power: natural gas-burning internal combustion engines run 3% to 5% more efficiently with HENG. Combustion is more complete, so less fuel is used. In addition, up to 7% less CO2 is emitted, and a reduction of 50% to 90% of NOx can be attained.