Mapping hydrogen demand
We started by mapping the largest point emitters in the area across power and industry. These fed into mapping of the hydrogen demand across multiple sectors: industry, power generation, transport, maritime and domestic heating. The potential hydrogen demands for large industrial users was calculated from their published emissions figures. For domestic heating, SGN supplied demand figures for its network.
The demands for the transport and maritime sectors required forecasts to be developed. As one of the biggest ports in the UK, Southampton is the starting point for thousands of heavy goods vehicles (HGV) journeys. As HGVs need to travel long distances and carry heavy loads, they are ideal candidates to use hydrogen, rather than battery electric power to replace diesel. We examined the annual HGV trips into and out of the port, estimating the uptake figures for hydrogen across a number of scenarios. With hydrogen-derived fuels offering potential for decarbonising the maritime sector, we also forecasted the potential hydrogen demand at the three ports in the area across a number of scenarios on the basis of the current number of ship calls currently and likely uptake.
The WSP team produced a number of demand forecasts for a low, medium and high uptake scenario utilising the National Grid’s Future Energy Scenarios (FES) as a basis; these demand scenarios enabled us to produce a base case scenario on which to base the concept design.
A transitioning energy economy
Engaging with stakeholders was vital, not just to build a picture of hydrogen demand but also to help with the economic vision and understand local support for the project. The Solent economy is an established energy economy, with many jobs dependent on the area’s diverse mix of large energy users and heavy transport. This dependence underpins its potential as a hydrogen hub, with decarbonisation presenting opportunities for a greener jobs and skills investment in the transition to a lower carbon economy.
To help inform the economic outlook, our economics team undertook economic modelling to understand the project costs and economic benefit. This included calculating the Levelised Cost of Hydrogen (LCOH) across four phases of the project up until 2050. This figure, which accounts for capital and operational cost, provides an understanding of the level of investment required. This work would enable local stakeholders to make a comparison with the costs of other decarbonisation pathways for the area.
Conceptual design
Our feasibility study included the design for the new scheme, inclusive of a low carbon hydrogen production facility, CO2 export facility and the network infrastructure required to facilitate a transition of the gas network to hydrogen. Through a ranking exercise we identified suitable sites for both the hydrogen production and export facility to export captured carbon for long-term storage via ship.
As hydrogen isn’t as energy dense as natural gas by volume, less energy can be stored in the pipeline network and additional storage is required. We commissioned a specialist consultant, GeoEnergy Durham, to examine the potential for underground storage in the area, inclusive of salt cavern storage potential and depleted petroleum reservoirs.
Phased roadmap
A hydrogen cluster isn’t something that can be turned on with the flick of a switch; it’s a journey that needs to be taken in careful steps. We created a phased roadmap, which envisages the scheme starting by constructing a hydrogen production and CO2 export facility supplying to an anchor demand, and then scaling up with the demand with more users coming online, and the gas network potentially converting to 100% hydrogen. If the scheme goes ahead, this process could see hydrogen production under way and the first demand nodes connected by 2030.
Following our feasibility study, SGN and Green Investment Group have signed a memorandum of understanding with Fawley petrochemical to explore the use of hydrogen and carbon capture to reduce greenhouse gas emissions in the Southampton industrial cluster.
