Green hydrogen certification scheme gets draft water emission norms

The Ministry of New and Renewable Energy (MNRE) has issued draft guidelines to quantify greenhouse gas (GHG) emissions arising from offsite water drawl and treatment under the Green Hydrogen Certification Scheme of India (GHCI). The draft, released on February 25, 2026, seeks feedback from green hydrogen producers and renewable energy industry associations by March 13, 2026.

The GHCI, launched in April 2025, sets out the framework for measuring, reporting, verifying and certifying green hydrogen production in India. Clause 7.4 of the scheme specifies that emissions from onsite raw water treatment are to be included in certification, while emissions associated with the physical extraction of water from natural sources are excluded. The clause also indicated that separate guidance would be issued for offsite water treatment emissions. The present draft fulfils that requirement.

The draft adopts a “Well-to-Gate” boundary, covering all stages of hydrogen production up to compression and onsite storage. It defines five supply scenarios, each with a separate methodology for calculating emissions.

Under Scenario A, where a producer owns and operates a captive offsite water treatment or desalination facility, emissions are to be calculated using primary metered data. Electricity consumption across pre-treatment processes, membrane systems such as Reverse Osmosis, and high-pressure pumping is to be included. Producers using dedicated renewable energy lines or power procured through a Power Purchase Agreement (PPA) may report zero electricity-related emissions if supported by load dispatch certificates.

Scenario B applies to water supplied by state agencies or municipal utilities, including Jal Boards, where the hydrogen producer does not control energy inputs. In such cases, a default Municipal Water Supply Benchmark listed in Schedule 1 applies, currently set at 0.603 kgCO₂e/m³. An exemption is available if the supplying agency certifies that the water supply line operates entirely on renewable energy.

Scenario C covers industrial clusters supplied by a common desalination or purification facility operated by a Special Purpose Vehicle (SPV) or a third-party entity. Emissions are to be allocated according to each producer’s proportion of water offtake. If primary energy data is not disclosed by the operator, a Common Desalination Benchmark of 3.017 kgCO₂e/m³ is to be applied.

Scenario D relates to tertiary effluent or recycled municipal wastewater. Only the additional energy used to upgrade water to electrolysis-grade quality is included, with a benchmark of 0.388 kgCO₂e/m³. Emissions from the initial municipal sewage treatment process remain outside the hydrogen production boundary.

Scenario E addresses cases where producers rely on multiple water sources. In such situations, a weighted average emission factor must be computed across all sources for each evaluation cycle. The figure is subject to verification by the accredited certification agency during annual audits.

The benchmark values are based on two reference parameters issued by the Central Electricity Authority (CEA): a Grid Emission Factor of 0.710 kgCO₂eq/kWh and a Transmission and Distribution loss factor of 17.63%. The draft also includes a compliance provision that allows the Technical Committee to authorise the use of the highest applicable benchmark during periods of documented water meter failure, to ensure conservative reporting.

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