The Isle of Grain, at the eastern edge of the Hoo Peninsula, is a vital part of Britain’s energy infrastructure with its huge liquefied natural gas (LNG) terminal, Grain LNG. The terminal has been operating for over 30 years and is Europe’s largest import facility, with a storage capacity of one million cubic metres. Now, with Centrica and Capital Partner’s planned acquisition of a 50% stake in the site, the terminal is once again in the spotlight.
Grain LNG terminal provides regasification and rapid-response storage to balance the UK’s energy system. Its throughput capacity is 15 million tonnes per annum, equivalent to 20% of UK gas demand. 100% of capacity at the terminal is contracted until 2029.
It seems to be a good deal for Centrica, who are intending to purchase the terminal from National Grid in a deal worth £1.5bn. But how significant is it to the UK’s energy future, and what is the impact on the local area?
LNG in the UK energy mix – how ‘clean’ is it?
Gas still accounts for 35% of UK energy use. With North Sea gas production in decline, the UK relies on imports to meet domestic demand. Most gas (around 75%) arrives via a gas pipeline from Norway, but the remainder is imported as LNG, mainly from ships arriving from the USA.
LNG is natural gas cooled to -162°C, reducing its volume by 600 times for shipping. Once delivered to a terminal like Grain, it is warmed back into gas (‘regasified’) for use in homes, power stations and industry.
The ability to import LNG provides flexibility during cold snaps and when renewable output is low. It also acts as a buffer against gas pipeline supply disruption. LNG was a critical resource during the 2022 energy crisis caused by the Ukraine war, as Europe had to urgently pivot away from reliance on Russian-owned gas pipelines. UK LNG imports hit a record high that year due to the country’s high LNG storage capacity. It acted as a ‘land bridge’, supplying regasified fuel from terminals like Grain LNG along pipelines to mainland Europe.
LNG is highly effective for energy security. It is also often promoted as a cleaner alternative to coal, emitting about 25% less CO₂ on a lifecycle basis. But its supply chain is energy intensive.
According to the International Energy Agency, extracting, liquefying, shipping and regasifying LNG adds about 20 grams of CO₂ equivalent per megajoule (MJ), compared to 12 g CO₂e/MJ for pipeline gas. One megajoule is roughly the energy needed to boil half a litre of water in a kettle.
So, for every kettle boiled using LNG, the extra emissions from liquefying and shipping the gas are equivalent to driving a petrol car 100 metres.
‘Go in, stay in, tune in’: safety and environmental risks
Grain LNG terminal is only around a mile from Grain village. Under the Control of Major Accident Hazards (COMAH) Regulations, Medway Council is required to maintain an emergency plan for the area in the event of any incidents, such as gas leaks. Fortunately, no such incident has occurred. If it did, a siren in the village would alert residents to: “Go in, stay in, and tune in.”
The terminal is also located in a sensitive area of marshland, part of the Thames Estuary and Marshes Ramsar site, and a Special Protection Area. National Grid, the current operator, works with the Environment Agency and ecologists to protect habitats and holds ISO 14001 environmental certification. Centrica and Capital Partners will need to retain these protections.
Net zero and future fuels
Centrica recognise that energy diversification is needed on Grain LNG to support a more sustainable energy future. CEO Chris O’Shea sees the Grain LNG Terminal as a key player in the “transition to net zero”, with future development options including hydrogen and ammonia bunkering capability on site.
These fuels are key to decarbonising shipping and heavy industry, but they would bring new hazards to the area. Hydrogen is highly flammable and disperses quickly, requiring advanced leak detection and ventilation. Ammonia is toxic even at very low concentrations, demanding robust containment, continuous gas monitoring, and specialist crew training.
While the terminal has stringent safety measures in place for handling LNG, if hydrogen or ammonia are introduced at the site, new environmental impact assessments and updated COMAH safety cases will be required. These would need to cover toxic gas scenarios, revised safety distances, and emergency plans for chemical exposure.
Community engagement would also need to be strengthened to address fears around new hazards. If not carefully managed, Centrica could see a repeat of the concerns raised by residents 14 years ago, regarding the risk of fatalities, and the fear of living so close to a hazardous site.
Kent at the crossroads of the energy transition
Centrica’s proposed investment secures a critical piece of UK energy infrastructure and retains Kent’s place at the heart of the country’s energy future.
LNG will remain part of the energy mix as Britain moves toward net zero. But, while better than coal, it is not emissions-free. Future fuels like hydrogen and ammonia have a key role in cutting carbon, yet they bring new safety and environmental challenges.
Centrica will need to balance its promise to “keep energy flowing reliably and affordably…as we transition to net zero” with the risks, ensuring Kent’s communities and ecosystems stay safe as the Grain Terminal progresses to a greener future.
