Flogas’ LNG powers Adapt Biogas biomethane-to-grid plant

Adapt Biogas is the first in the UK to generate its own onsite heat and electricity using liquefied natural gas (LNG) from Flogas.

Feeding two combined heat and power (CHP) engines, Flogas' LNG provides electricity to power Adapt's unique biogas-to-grid injection system, as well as heat, to kick-start its biogas production cycle.

The anaerobic digestion (AD) plant in Murrow, Cambridgeshire, is the UK’s first to inject biomethane at high pressure directly into the National Grid’s National Transmission System (NTS). Its current connection is set up for 2,000 m³ of biomethane per hour. However, a planned new injection line will support flows of up to 15,000 sm³, which is enough to supply more than 87,500 households with renewable gas annually. This will also support other AD sites with a lack of grid export capacity to reach their full production potential.

“Gas to grid injection is a highly comprehensive renewable energy solution, so we needed to find a way to generate our own reliable, uninterrupted power supply while keeping costs down,” said Sophie Swan, operations manager at Adapt Biogas.

“We also wanted to make sure we were using a low carbon fuel, minimising our impact on the environment. That’s why we decided to run our CHP engines on LNG. Not only is it one of the lowest carbon conventional off-grid fuels you can use, but it’s the most cost-effective solution for us. It also allows us to run effectively in island mode, reducing concerns about power outages or costly downtime.”

Shenton Group designed a turnkey solution comprising two 500 kW CHPs and a 330 kVA generator, as well as a system to monitor and react to the site’s mains connection condition. This allowed them to maximise power stability while complying with strict requirements from the distribution network operator.

These CHPs produce enough electricity and heat to power the gas injection process while also supporting its gas upgrading system, converting biogas to grid-ready biomethane. The upgrade enabled the new equipment to synchronise and cooperate with the CHP units already in place, providing cost savings and further sustainability benefits. An above-ground LNG tank adjacent to the AD plant and close to the engines and grid entry compound fuels the CHPs.

Mark Rutherford, Flogas’ national business development manager, commented: “This is the first time LNG has been used to power CHPs, plus it’s our first CHP biogas-to-grid solution, so it was really exciting to be part of such a unique project.

“Adapt Biogas has high volume, high-intensity fuel needs, so LNG was the most efficient and economical solution for them. Our expert engineers worked closely with the team from the start to create a fully bespoke system that would meet their exact fuel requirements and we managed the whole process for them, from design through to installation and commissioning.”

By using LNG to fuel its CHP engines, Adapt Biogas can prevent significant carbon emissions. This is because of LNG’s low CO₂e emissions compared to other common fuels. Flogas said it is ‘very happy’ to support Adapt’s effort to adopt low carbon fuels to meet climate change targets.