Design, Build, Install and Maintenance Contract for Halton Microgrid

BACKGROUND INFORMATION Halton Borough Council (HBC) is a Unitary Authority based in Cheshire, North West England, comprising the main towns of Runcorn and Widnes. The Council declared a Climate Emergency on the 16th October 2019.

Following the declaration, the Council developed an Action Plan which is predominantly focused on reducing the Council's own carbon production. The Council has developed a number of rooftop solar PV schemes and a 1.2MWp solar farm.

Whilst these projects have been invaluable, it became apparent to the Council that larger interventions would also be required in order to meet the Council's 2040 net zero target. With this in mind, the Council commissioned a feasibility study in early 2020 to evaluate the potential to construct a solar farm on Council owned wasteland.

The study concluded that the potential existed to construct a 3.62MWp solar farm on a closed landfill site located immediately north of Ditton Rd in Widnes (postcode WA8 0PG - Coordinates E: 350056, N: 385004). The site was historically used as a chemical waste landfill site, before being converted to a municipal golf course (St Michael's Golf Course).

The course was subsequently closed, and the site has been unused since. The Council are now planning to construct a 3.62MWp solar farm at the closed landfill site, which will be connected to the existing 1.2MWp solar farm via a new 11kV link.

The resulting 5.2MWp of solar PV generation will provide power to a number of council owned facilities in Widnes town via an extensive 11kV ring main which is to be installed as part of the project. The scheme will also incorporate a 2MW/4MWh battery storage scheme and a high-power electric vehicle charging hub at the Council's Lower House Lane transport depot.

On 1st June 2021 the Council secured a 6.1MVA export and 5.0MVA import grid connection offer from the local DNO (SP Energy Networks). On 27th June 2024, the Council submitted a planning application for the project, and the application was approved on 23rd January 2025.

During 2024, the Council has negotiated the necessary agreements to obtain construction access to the site. The Council own the land on which the scheme is to be built, all of the buildings, and will own the Microgrid once it is commissioned and handed over.

The Council are now seeking EPC (Engineer Procure and Construct) proposals for the turn-key detailed design, installation and commissioning of the Smart Microgrid Project, which will encompass the following key components; (a) A 3.62MWp solar farm, including all associated building and civil engineering works. (b) An 11kV link between the existing 1.2MWp solar farm and the new 3.62MWp solar farm.

(c) A 2MW/4MWh battery storage system at the new solar farm site. (d) An 11kV link from the new solar farm substation to a new Intake Substation located at the Council's Lower House Lane depot, including an associated horizontal drill under a major A Road.

(e) A new 33kV / 11kV Intake Substation (ISS) at the Council's Lower House Lane Depot. (f) New 11kV distribution substation infrastructure at four Council sites (Halton Stadium, Halton Leisure Centre, Municipal Offices and Lower House Lane Transport Depot) (g) A buried HV ring connecting the new Intake Substation (ISS) with the four distribution substations.

(h) High power EV and eRCV charging infrastructure at the Lower House Lane transport depot. (i) A SCADA control system to enable the efficient and optimal management of the completed microgrid system and the associated generation and storage assets.

The Tenderer's scope will include all works required to deliver a fully compliant, safe, efficient and working installation. Following completion of the construction works.