The Causeway Project

Delivering sustainable transport for Ireland with a Compressed Natural Gas (CNG) refuelling network

Causeway Project Overview

Sustainable alternative fuel for Ireland

Gas Networks Ireland is leading a project called the Causeway Study, under which a network of high capacity fast-fill CNG stations, a single renewable gas injection point and a vehicle grant are being delivered. Successful delivery of these objectives will demonstrate the validity of CNG and bioCNG as a viable alternative to diesel in Ireland while also helping to meet Ireland’s requirements under the EU’s Alternative Fuels Infrastructure Directive.

Progress to date

To date, the Causeway Study has seen the development of a renewable gas injection facility, the deployment of a fleet of CNG vehicles and the rollout of 4 CNG stations at Circle K Dublin Port, Circle K Cashel, Circle K Ballysimon Road and Circle K Clonshaugh.

CNG stations

In December 2018, Gas Networks Ireland and Circle K launched Ireland’s first publicly accessible fast-fill CNG station at Circle K’s Dublin Port station. A second public CNG station at Circle K’s Cashel premises on the M8 motorway opened in July 2020. In 2021, new transport corridors became available for CNG vehicles travelling in Ireland with the opening of two additional Circle K stations at Ballysimon Road, County Limerick and Clonshaugh, County Dublin. 

Each station has the capacity to fill up to 50 HGVs a day, with each fill taking no more than five minutes. There is a pipeline of additional public CNG progressing through the design, planning and construction project phases.

Renewable gas injection facility

Gas Networks Ireland successfully injected locally produced renewable gas into the gas network for the first time at Ireland’s only purpose-built injection facility in Cush Co. Kildare. The dedicated renewable gas entry point in Cush commenced commercial flows in May 2020 and joined Corrib as the only indigenous gas source on Ireland’s network following the closure of the Kinsale Head gas field. Once flowing at maximum capacity, Cush can supply renewable gas to approximately 11,000 homes.

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Moving to bioCNG today is a cleaner and reliable choice for fleet operators. To learn more or start your journey, please complete our contact form and one of the team will be in touch as soon as possible.

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The development of the CNG network via the Causeway Study is supported by a grant from the EU’s Connecting Europe Facility Transport Fund and the Gas Innovation Fund, approved by the Commission for Regulation of Utilities (CRU). Research is co-funded and conducted by project partner, the National University of Ireland, Galway.