Hydrogen: a practical solution to real energy problems

Like methane, hydrogen is flammable and colourless. Unlike methane, it is biologically inert and burns to water, without damaging emissions. One exciting application area for which hydrogen is being explored is the conversion of some gas networks to hydrogen on a localised and national basis. The goal is to decarbonise and provide energy solutions to current users of natural gas – including industry, commerce and domestic sectors.

Once these hydrogen network configurations exist, transportation networks in which the hydrogen passes through re-fuelling systems will become a reality. These can be used for displacing expensive, bottled storage of hydrogen or electrolysis at point of use. The idea is conceptually simple, and the technologies are largely ready and available today.

In domestic heating, the well-known interseasonal variations in energy demand between existing methane gas networks and electricity grids create multiple challenges. Within the UK, circa 30% of emissions are derived from such domestic heating. Equally, in locations such as the Netherlands, where existing methane supplies are at risk, hydrogen offers an elegant alternative to today’s energy systems.

Hydrogen at the point of use creates zero carbon emissions. This means using hydrogen in existing gas networks would reduce heating emissions to simply the by-product of water. Hydrogen vehicles are available today, yet suffer from the lack of an economic infrastructure, with the appropriate purity of hydrogen gas to support fuel cells. Hydrogen networks, with gas scrubbing technologies, will enable fuel cell infrastructures to be generated overnight. When compared to the equivalent cost per mile of electrical infrastructure, hydrogen delivered through the existing gas network is a far cheaper decarbonisation method – and the infrastructure is already there.

Across the supply chain, the cost to produce, transport, store, distribute and use hydrogen is attractive compared to alternatives.

The hydrogen landscape.

Production of hydrogen comes principally from two sources:

• Steam Methane Forming (SMR), which requires CCS (Carbon Capture and Storage) at scale in support of the process.
• Electrolysis from renewable sources, with typical efficiencies of circa 80%.

Low-pressure hydrogen (85 barg) will require slightly larger pipes and increased complexity in compressor stations, yet the cost is extremely low compared to that of the alternatives, and the transport properties of hydrogen are broadly similar to those of natural gas. The transport cost of hydrogen vs electricity vs district heating may be considered broadly in the ratio 1:7:49.

Another key benefit of hydrogen is that it allows for decoupling production from use demand, through appropriate storage, which creates efficiencies through the supply chain. Today, electricity and gas grids struggle with this input-output challenge. Compressed underground hydrogen storage is entirely proven around the world; one example is that of PRAXAIR, Texas. Fundamentally, reducing the cost of the supply chain starts with increasing the operating hours of the producer. Hydrogen storage enables that.

What about the suitability of our current gas distribution network for transporting hydrogen? In the UK, most of the low-pressure distribution system is now polyethylene and operates at 25-75 mbar. Taken from as far back as the 18th World Hydrogen Energy Conference, Detlef Stolten and Thomas Grube stated: “In summary, according to the tests performed in this study, we have found strong indications that polyethylene gas pipes can be used for the transportation of hydrogen without any adverse effects. The same indications have been found for both new and old pipes in the Danish natural gas distribution network.”

Kiwa today offers re-fuelling certification services and testing of hydrogen systems, with facilities up to 4500 bar pressures, across trains, buses, domestic and commercial vehicles. Across the UK, we are involved in a number of key infrastructure projects, such as Hy4Heat, H21, Hydeploy, and H100, all looking at different aspects of conversion to hydrogen. Also in the UK, we have invested in piped hydrogen testing facilities – a UK first. In the Netherlands, investments in tank testing provide best-in-class tank testing facilities, while numerous projects are underway with the Dutch networks to rapidly accelerate network transition.

Mark Eldridge, Global Hydrogen Sector Lead at Kiwa UK, tells: "We strongly believe in the future of hydrogen at multiple points of the energy system, for production, transport, storage, distribution, and use. Hydrogen complements a multi-vector energy system and addresses the intermittency issues for electricity generation."

"Kiwa offers unique and extensive services across the whole hydrogen supply chain, from production to end use. The same supply chain will also require extensive education of stakeholders, from consumers, policy makers, engineers, manufacturers, installers to service teams to enable a complete hydrogen systems integration to be a reality. By supporting our clients in their respective challenges, we look to play a key part in the continually growing Hydrogen Economy, in support of a wider, more integrated future energy system as the need and the demand to decarbonise across the globe increases."