NI Water has unveiled a £7m solar farm at Dunore water treatment works in Co Antrim that should significantly reduce its carbon footprint.
The green power station is located on a 33-acre site on the eastern shore of Lough Neagh, close to Belfast International Airport.
The utility is Northern Ireland's heaviest user of electricity and Dunore is its third largest site in terms of energy consumption, accounting for 7% of the company's annual usage.
The new facility is expected to save it more than £0.5m annually in energy costs.
NI Water said that the flagship project - which uses 24,000 solar panels - has "dramatically reduced its carbon footprint".
Commenting on the completion of the project, CEO Sara Venning said: "As the largest user of electricity in Northern Ireland, we are committed to finding innovative renewable energy projects to reduce our expenditure on power, which has already tumbled by £5m over the last three years.
"The Dunore solar farm is a major step toward reaching our goal of increasing electricity consumption from renewable sources from the current 13% to 40% by 2021.
"As a company, we operate nearly £3bn worth of assets, all working to provide 570 million litres of clean drinking water and recycling 340 million litres of used water safely back to the environment.
"Our commitment is to ensure we operate as efficiently and cleanly as possible, safeguarding our environment for future generations."
She added: "Dunore is one of many innovative renewable energy projects which NI Water is developing to ensure we become more energy efficient while also making cost savings to our business.
"This flagship project will also save around 2,000 tonnes of carbon every year."
Leo Martin, managing director with civil engineering firm Graham, added: "Graham is delighted to have completed this major project for NI Water.
"It's an impressive achievement, with 24,000 solar panels now helping to provide a peak output of 4.99 megawatts, with spare capacity going to the grid.
"Like all of our NI Water projects, the Dunore solar farm - where we also worked alongside our suppliers RPS, Greencells and Scotts Electrical - was only successful because of the openness of NI Water's operational staff integrating with the Graham team.
"This is the latest in a series of hugely successful collaborative projects between NI Water and Graham.
"For example, working as part of the contractor team for NI Water's integrated wastewater framework, we delivered new-build treatment works, upgrades to existing treatment works, pumping stations and pipeline construction across around 100 separate schemes.
"We look forward to continuing our ongoing successful collaborative partnership with NI Water for many years to come and delivering lasting impact."
The Dunore Solar Farm is an important element in the company's strategy to continue to deliver improvements for customers and the environment.
As part of an engagement project with the local community during the construction phase, NI Water organised a poetry competition for local schools which was won by Laura Daly, a P7 pupil from St Joseph's Primary in Crumlin.