NI Water switches on £2.3m of hydro turbines at three sites

NI Water has completed a £2.3m investment in hydro turbines at Ballygomartin Water Pumping Station, Breda Service Reservoir and Purdysburn Service Reservoir. The project was supported by the Department for the Economy's Invest to Save funding within the 2021-27 price control period (4NI). It is part of NI Water's Energy Reduce Use Programme.

900 MWh

Source: NI Water via 4NI ↗

What we know

• Output: around 900 MWh a year across the three sites. NI Water likens this to the annual electricity use of about 360 homes, using Ofgem's 2,500 kWh benchmark.
• Ballygomartin: a 63kW turbine is expected to power the pumping system itself and export the surplus. The station pumps about 3.5 million litres a day to Whiterock Upper Service Reservoir, serving roughly 4,700 domestic and 600 non-domestic customers (WaterBriefing). No ratings were given for Breda or Purdysburn.
• Grid: the turbines become the sites' main energy source, with surplus electricity exported to the grid.
• Delivery team: BSG was main contractor, Hydroplan design lead, and McAdam Design provided design support.

Damien O'Mullan, NI Water's director of transformation and innovation, said the installations will "help offset grid electricity use, and reduce costs and carbon emissions". Katrina Duddy, head of energy management at the Department for the Economy, said the turbines capture energy "from water already moving through NI Water's infrastructure".

What others are reporting

The project was first announced in early October. 4NI and WaterBriefing carried the site-level detail on Ballygomartin and the delivery team.

Background

In written evidence to the Assembly's Economy Committee in July, NI Water said it is Northern Ireland's single largest electricity consumer. It accounts for over 3% of total demand and about 10% of the industrial sector (NI Assembly). The submission backed the bill and stressed the role of major consumers in demand reduction and on-site generation.

On-site renewables are not new for the company. Its 4.99MW solar farm at Dunore, opened in 2018 at a cost of £7m, was expected to supply 7% of its annual electricity use. At that point the company set a target of raising renewables from 13% to 40% of consumption by 2021 (NI Water).

What we don't know yet

NI Water has not published the expected payback period, or the share of the £2.3m covered by Invest to Save. Nor has it said what proportion of its total consumption it now meets from its own renewable generation.

What to watch

• Whether more turbine sites follow under the Energy Reduce Use Programme in the next price control.
• Progress of the Utility Regulator decarbonisation bill, and any funding route it creates for utility on-site generation.