Hydrogen blending in piped gas for household consumers could move towards a regulated commercial framework after the Petroleum and Natural Gas Regulatory Board floated draft guidelines for mixing hydrogen with natural gas in domestic piped natural gas networks.
The draft guidelines cover hydrogen-natural gas, or HNG, supplies delivered through city gas distribution networks to domestic consumers. They prescribe minimum requirements for commercial supply and are designed around single-point hydrogen injection into small, hydraulically defined deployment areas confined to household users, according to the regulator’s draft.
PNGRB has specified 5 per cent hydrogen by volume as the maximum commercial blend limit. It has also clarified that this figure is not intended to be the routine operating target for gas distribution systems. The normal operating setpoint must be lower and sufficient to prevent hydrogen injection from exceeding the permitted level during peak or minimum demand, start-up, shutdown and system disturbances.
The proposed framework therefore links the permitted blend not only to the composition of the gas supplied to households, but also to how the network is monitored and controlled. The draft defines the maximum commercial blend limit as 5 per cent hydrogen by volume, demonstrated through measurement and verification arrangements in the approved area.
The approach is focused on controlled deployment rather than an immediate change across entire city gas networks. Restricting the initial commercial application to small, hydraulically defined areas and domestic consumers would allow the regulator and network operators to manage injection points, operating conditions and verification within a specified part of a distribution system.
The proposal follows PNGRB’s earlier work on using existing gas infrastructure for hydrogen transportation. In March 2024, the regulator said it was examining avenues for transporting green hydrogen through natural gas transmission lines by blending hydrogen with natural gas. It had identified gas transmission lines as a first choice for transporting green hydrogen.
Hydrogen is regarded as a flexible energy carrier and can be used in applications including renewable-energy integration and transportation. In the household-gas context, however, the draft guidelines place emphasis on maintaining operating control as hydrogen is introduced into networks supplying domestic customers.
For city gas distribution companies, the proposal establishes a framework in which hydrogen injection, operating setpoints and measurement arrangements would need to work together. The draft does not establish a routine 5 per cent supply target; instead, it sets an upper commercial limit and requires the operating level to remain lower under normal conditions.
The guidelines remain in draft form, and the material supplied does not specify the next procedural milestone or the timeline for final notification. Any wider rollout will depend on the final regulatory framework and the approved deployment areas identified under the measurement and verification arrangements.
