Ynni Ystradau 2026 Tender

Original: Ynni Ystradau - Tanygrisiau Heat Network

Ynni Ystradau

About this tender

Ynni Ystradau, a Community Benefit Society, seeks a consultancy team to design a water source heat pump (WSHP) and district heat network for Tanygrisiau, North Wales. The scheme would serve around 200 homes, a handful of non-domestic properties and the Rehau factory, extracting heat from Tanygrisiau Lake. The buyer wants the scheme progressed to RIBA Stage 3 with full costings, plus identification of the licences, permits, consents, approvals and legal agreements needed to deliver it. The buyer also wants to explore integrating solar PV, thermal energy storage and battery storage where these improve performance, resilience and project economics. The work is split into two lots. Lot 1 covers the WSHP system and heat extraction from the reservoir (in consultation with Engie, which owns the lake and pumped storage facility), WSHP housing and pumps, sizing of thermal and electrical storage, heat network design parameters, and running costs and staffing levels. Lot 2 covers detailed design of each phase of the heat network infrastructure, including pipe routing between the reservoir, energy centre, factory and residential areas, zoning, a phased development plan, and running and maintenance costs. The design assumption is a network flow temperature of about 55C, with alternatives possible only with justification and agreement. An ambient loop is not proposed. Tenderers must demonstrate 3D digital modelling and BIM capability, share designs on common platforms, and show previous relevant work. Bidders may bid for one or both lots and must state willingness to work with other bidders and with local civil engineering and geology-aware firms on heat network routing. Welsh Government funding conditions require 15% recycled material by value, a waste and resource reporting requirement at practical completion, a Mandatory Project Bank Account for subcontractor payments, and a description of community benefits. Community benefit is a stated priority, particularly training, upskilling of young people and local contractors, work experience and internships. The design and specification stage (RIBA Stages 2-3) is expected to run from November 2026 to March 2027, with an inception meeting in the week commencing 16 November 2026. The successful supplier must attend at least three in-person meetings, which may be held in Blaenau Ffestiniog, plus fortnightly online meetings with the buyer.

Bidder eligibility

Insurance is a condition of tender: Public Liability GBP 10M, Employers Liability GBP 10M and Professional Indemnity GBP 10M, held or to be obtained for the contract. Responses must not exceed 12 pages of A4 at 11-point. Bidders must demonstrate necessary skills and experience, examples of previous work, 3D/BIM modelling capability, and brief biographies of key staff. Bidders must confirm willingness to work with other professional services and local civil companies, and to work with other tenderers where bidding for all lots. Consortia bidding is permitted, and a lead consultant must receive and distribute fees if working as a partnership. A Carbon Reduction Plan is required. An SPD is not required. Procurement is a single-stage mini-tender restricted to qualified companies.

How bids are scored

Weighted score out of 100, with the highest score being best: Necessary skills and experience 20; How well the response fits the needs of the tender 30; Quality of the response 20; Cost 20; Social and community benefit offered 10. Each response is marked by three evaluators who must give written explanations for their scores. The buyer reserves the right not to award the contract. Price split is 20% cost and 80% non-price. A fixed price and a price breakdown for each lot and task are required.

Lots

• Lot 1: Water source heat pump system and energy storage design

  Design of the WSHP system and heat extraction from the reservoir in consultation with Engie; WSHP housing and pumps; assessment and sizing of thermal and electrical storage; liaison with Energy Local; heat network design parameters including operating temperatures and hydraulics; technical, operational and commercial optimisation; running costs and staffing levels; full designs and costs; identification of licences, consents and legal agreements.

• Lot 2: Detailed heat network infrastructure design

  Detailed design of each phase of heat network infrastructure, including pipe routing between the reservoir, energy centre, manufacturing facility and residential areas; zoning of development stages; phased development plan; full designs and costs; running and maintenance costs; identification of licences, consents and legal agreements.

Key requirements

• ✓RIBA Stage 3 design development for water-source heat pump and district heat network system
• ✓Design of heat extraction from reservoir, WSHP housing, pumps, and distribution network for ~200 homes and non-domestic properties
• ✓Integration of complementary renewable technologies (solar PV, thermal energy storage, battery storage) where viable
• ✓Optimised, technically robust and commercially viable design with full costing
• ✓Consultation with Engie (lake owner) on water extraction points and discharge options
• ✓Obtaining licences, consents and approvals necessary for project delivery

Procurement contact

The notice names a procurement contact for clarification questions.

Relevant sectors

About this sector

Renewable energy funding covers solar, wind, hydropower, geothermal and bioenergy, from early research to grid-scale deployment. Public money tends to back demonstration, grid connection and access to energy in emerging markets, while procurement notices buy installation, operation and maintenance. Calls often ask for proof of resource assessment, permitting progress and local partners.