BLOG: The need for low carbon hydrogen of all colours

In light of the recent debate around blue hydrogen, NWHA Chair Professor Joe Howe considers why we need low carbon hydrogen from a range of sources.

Our entire energy system needs to be decarbonised rapidly to prevent the damaging and evident effects of climate change.  There is no single solution – we need to deploy multiple approaches to transition as quickly as possible to clean energy.  Low Carbon Hydrogen is a key part of our future clean energy system alongside multiple other solutions, including increased electrification, that need to work together to deliver net zero. Hydrogen has a vital role to play in decarbonising ‘hard to reach’ sectors of the economy, such as industry, flexible power generation, heavy transport and heat – furthermore, it offers energy system flexibility at times of low renewable electricity generation or peak heat demand.

We need to recognise and address the scale of the energy challenge at pace. The UK leads the world in offshore wind deployment and is by far the UK’s biggest growing renewable sector. In 2019 this delivered 32TWh. This equates to around 2% of our total energy demand. There is an ambitious target to quadruple this by 2030. Even this vital expansion in offshore wind electricity generation is unlikely to deliver more than 10% of total energy sources, even including wider efficiency savings and demand reduction. Even alongside the other low carbon and renewable electricity sources, this won’t be sufficient to decarbonise today’s electricity sector, let alone the increase in electricity demand from electric vehicles and other uses. It leaves more than 75% of our energy system untouched.

Every year that goes by we emit another 350+ million tonnes of carbon dioxide. We therefore simply cannot wait to replace our entire energy system with renewable electricity (directly or via hydrogen).

As the Climate Change Committee (CCC) makes clear, we need low carbon hydrogen produced from all sources – from renewable electricity (‘green’ hydrogen), from natural gas with Carbon Capture and Storage (CCS) (‘blue’ hydrogen), as well as from waste and biomass resources which can provide Greenhouse Gas Reduction when combined with CCS.  The climate crisis means that we don’t have the luxury of time to focus only on individual technologies.

Natural gas is an available source of energy which contains carbon and hydrogen. Before we deliver that energy to users, we can remove the carbon and put it back into the underground geological formations that the natural gas originally came from.  This process avoids the carbon being released to the atmosphere by storing it permanently.

This can be done with overall carbon savings of 85%, and potentially more. Every 12TWh of natural gas we use in today releases around 2.4 million tonnes of CO2e to the atmosphere including upstream emissions. Delivering that same amount of energy as blue hydrogen will reduce emissions to the atmosphere by over 2 million tonnes of CO2e.

This is a game-changing saving, particularly when aggregated over time, as blue hydrogen can be deployed rapidly and at scale. Of course, we also need solutions that solve the last 10-15% of these emissions – and this will happen in time – whether it is improved blue hydrogen, green hydrogen from 100% renewable sources, or Greenhouse Gas Reductions from Bio-hydrogen with CCS and Direct Air Capture. However, the highest priority is to bank the savings we can make quickly and at scale now. Just like discounted cashflows, the savings we can make in the short term are critical.

It will take us a number of decades to build renewable electricity-based sources at sufficient scale to make substantial contributions to hydrogen production, and blue hydrogen buys us that time. A project which removes 2 million tonnes of CO2e per year from 2025 will remove more CO2e in aggregate by 2050 than a project that removes 2.4 million tonnes per year starting in 2030.

It also enables us to establish hydrogen infrastructure. It underpins the networks to deliver hydrogen and the storage to enable us balance our energy system, just like we do today with gas. That infrastructure is agnostic to the colour of hydrogen. Over time, the sources of hydrogen it carries can evolve as they each play their part in delivering Net Zero.