Low Carbon Heat on a City Scale with Hydrogen - Leeds City Gate Report

The H21 Leeds City Gate report was launched on 11th July 2016. This outlines the feasibility of converting the gas grid to deliver hydrogen for heating and cooking, starting with the Leeds city region and then for conversion to take place across the country incrementally. The report finds that converting the UK gas grid to hydrogen will be a major step towards meeting the UK’s carbon reduction targets. This conversion could start in Leeds by 2026, with total estimated conversion costs of £2bn for the whole of Leeds.

Currently, over 30% of all UK carbon emissions come from domestic heating and cooking. A UK-wide conversion to hydrogen gas will reduce heat emissions by a minimum of 73% as well as supporting decarbonisation of transport and localised electrical generation.

Leeds City Gate was undertaken by Northern Gas Networks (NGN), Kiwa Gastec, Amec Foster Wheeler and Wales and West Utilities backed up with significant carbon capture and storage (CCS) development. It outlines the benefits from replacing natural gas in the UK city’s gas grid with ‘green’ H2. However, the report indicates that in order for the H2 to be truly low-carbon, any CO2 generated during the production of H2 by steam methane reforming needs to be captured and securely stored using CCS. One of the key findings is that CCS and H2 can together help deliver efficient decarbonisation of heat at a city scale.

The project outlines how Leeds’s gas network can be supplied with ‘green’ H2 produced in Teesside by steam methane reformation of natural gas, with the H2 transported by high pressure (up to 80bar) pipeline to Leeds where it connects into the high pressure (17 bar) outer city ring main and then distributed into the below 7 bar local network. This network could then be used to provide the H2  fuel for heating and cooking in homes across the city.

This new approach proposed by Leeds City Gate report could provide a pathway to slashing these emissions from space heating and cooking. Burning H2 instead of natural gas produces water rather than emitting carbon dioxide (CO2). Capturing the CO2 from the H2 production units at Teesside and transporting it for offshore sequestration could result in a 73% drop in CO2 emissions for the entire system as compared to burning natural gas at present.

Stuart Haszeldine, Director of the Scottish Carbon Capture and Storage (SCCS) said: “Replacing the use of natural gas with H2 for heating and cooking would almost completely decarbonise these systems. These have so far been a very difficult area of emissions to effectively reduce without digging up urban streets and at acceptable cost. CCS and H2 represent a winning combination for UK decarbonisation efforts.”

Northern Gas Networks (NGN) explained that a nationwide move away from methane to a hydrogen grid was "technically possible and economically viable". Dan Sadler of NGN added: "This is a major opportunity for our country to become a world leader in hydrogen technology and decarbonisation and would create thousands of new jobs across the UK."

The city of Leeds was selected as the test region for the £260,000 H21 Leeds City Gate initiative. A subsequent and incremental rollout across the UK would considerably reduce carbon emissions from homes and make a huge contribution towards the Climate Change Act’s target of an 80% reduction by 2050.