Nitrous Oxide emissions associated with 100% hydrogen boilers: research

Background

The Scottish Government’s Directorate for Energy & Climate Change commissioned an analysis of emissions from the combustion of hydrogen in domestic boilers.

The aim of this exercise was to measure the gas composition of flue gas from hydrogen boilers under normal (real world) operating conditions, with a view to establishing what, if any, greenhouse gases are emitted during combustion.

Previous research was conducted by ACE Research and Energy Savings Trust and commissioned by ClimateXChange (CXC) on behalf of the Scottish Government. This aimed to establish the greenhouse gas emissions associated with the most common and readily available zero and low carbon heating technologies

The findings of the research were inconclusive regarding 100% hydrogen fuelled appliances with the report highlighting that there could be very limited ‘trace’ amounts of nitrous oxide (N₂O) emissions involved in the combustion of hydrogen within boilers.

As N₂O is treated as a greenhouse gas within section 10 of the Climate Change (Scotland) Act 2000, it was desirable to conduct measurements of N₂O emissions from hydrogen appliances in a realistic domestic environment under typical operating conditions.