Ynni Ystradau - Tanygrisiau Heat Network

Invitation to tender

Ynni Ystradau seeks tenders for the provision of Design services for RIBA Stage 3 design of a district heat network in Tanygrisiau.

Project Background

Ynni Ystradau is developing a heat network and water source heat network for space and hot water heating for the village of Tanygrisiau (around 200 homes and a handful of non domestic properties) and Rehau’s factory. Initial feasibility studies are available here xxx. Heat would be extracted from the water in the Tanygrisau Lake. Two local hydros will power the WSHP via a local energy market.

Ynni Ystradau (YY) is seeking to appoint a suitably qualified and experienced consultancy team to undertake the design and development of a proposed water source heat pump (WSHP) and heat network scheme in Tanygrisiau, North Wales.

YY now wishes to progress the scheme to RIBA Stage 3 and obtain the licences, consents and approvals necessary to support project delivery.

YY is also interested in exploring the integration of complementary renewable and low-carbon technologies, including solar photovoltaic (PV) generation, thermal energy storage and battery energy storage systems, where these can enhance system performance, resilience, renewable energy utilisation and overall project economics.

Discussions with Engie who own the Lake and run the associated pumped storage facility have identified valves in the dam wall as water extraction points, there are a number of options for discharge.

Scope of Services

Feasibility studies, site information, heat demand assessments and other supporting documentation are available at xx.

Tendees should provide an optimised, technically robust and commercially viable design for each phase of the project. The scope of services must include:

Development of the scheme design to RIBA Stage 3 with full costing:

Lot 1

Design of water source heat pump system and heat extraction from reservoir in consultation with Engie,

Design and location of the WSHP housing and associated pumps.

Assessment and sizing of thermal and electrical energy storage systems in conjunction with evaluation of the heat demand of homes via energy efficiency retrofit and liaison with Energy Local as to the requirements to optimise the use of local generation.

Design and location of heat and electrical storage.

Development of heat network design parameters, including operating temperatures and hydraulic requirements.

Technical, operational and commercial optimisation of the overall scheme.

Running costs and staffing levels required.

Full designs and costs.

Identification of any licences, permits, consents and approvals required

Identification of Legal agreements required.

Lot 2

Detailed design of each phase heat network infrastructure, including:

Routing of pipework between the reservoir, energy centre, manufacturing facility and each residential development areas.

Zoning of different stages of development.

Plan for the phased development of the heat network.

Full designs and costs

Running and maintenance costs.

Identification of Legal agreements required.

Identification of any licences, permits, consents and approvals required

Current design assumptions are that network flow temperature of approximately 55°C; however, in the course of the work alternative temperatures could be proposed with suitable justification but only progressed with agreement with YY. Note we are not proposing using an ambient loop.

Tendees must demonstrate capability in the production of 3D digital models, share designs on common platforms and provide BIM models as appropriate.

Tendees must provide examples of previous work and experience.

Tendees may bid for all or one of the lots. If bidding for one lot, they must describe how they will work with other successful bidders. If bidding for all the lots, tendees must indicate if they are prepared to work with other tendees for one lot.

All Tendees much indicate that they are prepared to work with other professional services and local civil companies who

Invitation to tender Ynni Ystradau seeks tenders for the provision of Design services for RIBA Stage 3 design of a district heat network in Tanygrisiau. Project Background Ynni Ystradau is developing a heat network and water source heat network for space and hot water heating for the village of Tanygrisiau (around 200 homes and a handful of non domestic properties) and Rehau’s factory. Initial feasibility studies are available here xxx. Heat would be extracted from the water in the Tanygrisau Lake. Two local hydros will power the WSHP via a local energy market. Ynni Ystradau (YY) is seeking to appoint a suitably qualified and experienced consultancy team to undertake the design and development of a proposed water source heat pump (WSHP) and heat network scheme in Tanygrisiau, North Wales. YY now wishes to progress the scheme to RIBA Stage 3 and obtain the licences, consents and approvals necessary to support project delivery. YY is also interested in exploring the integration of complementary renewable and low-carbon technologies, including solar photovoltaic (PV) generation, thermal energy storage and battery energy storage systems, where these can enhance system performance, resilience, renewable energy utilisation and overall project economics. Discussions with Engie who own the Lake and run the associated pumped storage facility have identified valves in the dam wall as water extraction points, there are a number of options for discharge. Scope of Services Feasibility studies, site information, heat demand assessments and other supporting documentation are available at xx. Tendees should provide an optimised, technically robust and commercially viable design for each phase of the project. The scope of services must include: Development of the scheme design to RIBA Stage 3 with full costing: Lot 1 Design of water source heat pump system and heat extraction from reservoir in consultation with Engie, Design and location of the WSHP housing and associated pumps. Assessment and sizing of thermal and electrical energy storage systems in conjunction with evaluation of the heat demand of homes via energy efficiency retrofit and liaison with Energy Local as to the requirements to optimise the use of local generation. Design and location of heat and electrical storage. Development of heat network design parameters, including operating temperatures and hydraulic requirements. Technical, operational and commercial optimisation of the overall scheme. Running costs and staffing levels required. Full designs and costs. Identification of any licences, permits, consents and approvals required Identification of Legal agreements required. Lot 2 Detailed design of each phase heat network infrastructure, including: Routing of pipework between the reservoir, energy centre, manufacturing facility and each residential development areas. Zoning of different stages of development. Plan for the phased development of the heat network. Full designs and costs Running and maintenance costs. Identification of Legal agreements required. Identification of any licences, permits, consents and approvals required Current design assumptions are that network flow temperature of approximately 55°C; however, in the course of the work alternative temperatures could be proposed with suitable justification but only progressed with agreement with YY. Note we are not proposing using an ambient loop. Tendees must demonstrate capability in the production of 3D digital models, share designs on common platforms and provide BIM models as appropriate. Tendees must provide examples of previous work and experience. Tendees may bid for all or one of the lots. If bidding for one lot, they must describe how they will work with other successful bidders. If bidding for all the lots, tendees must indicate if they are prepared to work with other tendees for one lot. All Tendees much indicate that they are prepared to work with other professional services and local civil companies who know the geology of the land for the design of the route of the heat network. They must describe how this relationship would be set up. In accordance with the conditions of funding by the Welsh Government the project design must meet the following criteria The tendee must indicate how their design includes 15% recycled material by value in the construction Include the requirement for at practical completion, a report to be provided to the client in accordance with Waste and Resource Action Programme. Desribe how their proposed approach to the design and build will maximise the the community benefits delivered through the funding and all subcontractirs during this phase and the build stage. Confirm they will use a Mandatory Project Bank Account as a means of ensuring fair and prompt payment of sub-contractors. Design Team The tendee may propose all work to be carried out in house in conjunction with local civil company or as a partnership. If working as a partnership their must be a lead consultant who will receive and distribute fees. Tendees must give brief biographies and skills of key members of staff expected to work on the project. Monitoring and Reporting The Tendee must provide a description of how they will monitor performance and reporting to the client. Pricing Tendees should give a breakdown of prices for each Lot and each task. Response must be a fixed price. Procurement process Procurement of the work will be undertaken a single stage competitive mini-tender to qualified companies. Community Benefits As a Community Benefit Society, one of the main goals of YY is to provide local training opportunities and upskilling to young people and local contractors, as well as growing local supply chains. Tenders must demonstrate how they will provide community benefit in these areas. We would be particularly interested in approaches offering work experience or internships in the area. Meetings Successful tendees will be required to attend meetings meet at least 3 times during this stage of the project in person. Meetings may be held at locations in Blaenau Ffestiniog. Fortnightly on line meetings with YY are also expected NOTE: To register your interest in this notice and obtain any additional information please visit the Sell2Wales Web Site at https://www.sell2wales.gov.wales/Search/Search_Switch.aspx?ID=171968. The buyer has indicated that it will accept electronic responses to this notice via the Postbox facility. A user guide is available at https://www.sell2wales.gov.wales/sitehelp/help_guides.aspx. Suppliers are advised to allow adequate time for uploading documents and to dispatch the electronic response well in advance of the closing time to avoid any last minute problems.

Timetable Stage Date Call off request issued 16/10/2026 Question & Answer period closes 31/10/2026 date for return of call off response 06/11/2026 Inception meeting / contract starts Week commencing 16/11/2026 The design and specification process (RIBA Stages 2-3 ) will take place between November 2026 and March 2027. Insurances It is a condition of this tender that applicants hold, or will obtain for the purposes of this contract, the following insurances: Public Liability £10M Employers Liability £10M Professional Indemnity £10M Reponses Reponses should be no more than 12 pages A4 11 point. Scoring Each tender will be scored on the following basis, the highest being the best. Criteria Percentage Necessary skills and experience 20 (marked out of 20) How well the response fits the needs of the tender 30 (marked out of 30) Quality of the response 20 (marked out of 20) Cost 20 (marked out of 20) Social and Community benefit offered by the response 10 (marked out of 10) Responses will be marked by 3 people, each giving an explanation for the scores given. Ynni Ystradau reserves the right not to award the tender to any response. Price It is a tender requirement that you provide a breakdown of your price. Your tender submission must be saved on the sell2Wales website before 6/11/2026 5pm

Price

It is a tender requirement that you provide a breakdown of your price.

Your tender submission must be saved on the sell2Wales website before 6/11/2026 5pm

(WA Ref:171968)

Under the terms of this contract the successful supplier(s) will be required to deliver Community Benefits in support of the authority’s economic and social objectives. Accordingly, contract performance conditions may relate in particular to social and environmental considerations. The Community Benefits included in this contract are:

As a Community Benefit Society, one of the main goals of YY is to provide local training opportunities and upskilling to young people and local contractors, as well as growing local supply chains. Tenders must demonstrate how they will provide community benefit in these areas. We would be particularly interested in approaches offering work experience or internships in the area.

The buyer considers that this contract is suitable for consortia bidding.