Seeking expertise for Industrial Waste Heat Recovery and Decarbonisation Assessment for Alcumatic Foundry in Sønderborg

Background

In Sønderborg, Denmark, a growing interest in industrial decarbonization has led to the exploration of waste heat reuse among small and medium-sized enterprises (SMEs). While many SMEs generate waste heat through various processes, these sources are typically small and fragmented. As a result, traditional assessments – focused on single processes – fail to present a conclusive business case for investment. There is a wish to change that by developing a holistic methodology that can be applied across SMEs, starting with a pilot case at a local foundry, called Alcumatic.

Project Outset: The Challenge of Fragmented Waste Heat Sources

Waste heat potential has been identified at several SMEs, but current studies and analysis tend to lack synergy and are limited to individual processes within companies. This siloed approach lacks symbiosis which often leads to sub-optimization, where investments are made in isolated systems that don’t maximize overall efficiency. The key insight is that optimal reuse may lie in interlinking multiple processes—an approach that requires a broader, integrated energy flow analysis.

This assignment is intended to help move from fragmented audits toward evidence-based decision-making. By combining continuous on-site measurements (24/7) at Alcumatic over a two-week period with the already available energy consumption data for a full calendar year (and corresponding weather data), Sønderborg and Alcumatic aim to build a complete picture of energy and waste heat flows across operations. The resulting analysis will be used to evaluate and compare practical options such as ventilation integration, heat recovery, heat pumps, energy storage, potential district heating connection, and electrification pathways including higher-temperature applications. The goal is to produce a business case at a level where Alcumatic’s management can make investment decisions and initiate a sourcing process for detailed engineering, while also capturing lessons that can feed into a generic methodology for other SMEs within Sønderborg and beyond.

Delivery will require close collaboration between the City of Sønderborg, the Alcumatic management and operational teams, and relevant experts from the NetZeroCities consortium (who will support baseline briefings, alignment with the overarching strategic approach, and sharing of good practices where relevant). The work also needs to fit the realities of an active production site and a tight milestone plan from May to September, including scheduling of on-site access, installation and removal of measurement equipment, and review points for interim outputs. In addition, solution design must fit the specific conditions of an aluminium foundry, including ventilation requirements and fire-risk considerations, and should take into account that district heating may be rolled out to the local area and could influence storage and system design assumptions.

About the request

The proposal should consider the following. Please note, outputs are expected at a decision-support/pre-feasibility level sufficient to initiate a next project stage, while detailed design, engineering and associated calculations or obtaining equipment quotations remain out of scope.

Phase 1 Total energy flow analysis and definition of the optimal heat recovery setup

The Supplier will:

Design the overall approach for developing a total site energy balance, including how data to be measured and existing site data will be combined to characterise energy and waste heat flows across processes at Alcumatic foundry.

•  Define and implement a continuous (24/7) on-site measurement campaign over a two-week period, including selection of measurement points, measured parameters, required accuracy, and data quality control. The two-week measurement period is expected to cover a representative production cycle, to be confirmed during the start-up phase in coordination with the foundry.
• Provide the necessary measurement equipment and oversee installation, commissioning, troubleshooting (if needed), and removal in coordination with the foundry’s operational team. The level and type of measurement equipment is expected to be appropriate to a pre-feasibility/decision-support level of analysis.
• Consolidate measurement results with available energy consumption data for a full calendar year (as per “background” section: monthly data for gas consumption and 15-minute interval data for electricity consumption) and corresponding weather data to build a measurement-informed “as-is” energy balance model for the site, e.g. through a Sankey diagram or equivalent.
• Identify and quantify key waste heat sources and heat demands and analyse matching opportunities across processes to avoid sub-optimisation.
• Define the optimal heat recovery configuration for the site, explicitly comparing a single integrated system versus multiple combined /coordinated systems and assess their relative technical feasibility and expected performance.
• Develop initial future energy balance scenarios to compare the different potential alternative heat recovery setups (see previous point) and provide a basis for subsequent assessment of electrification, flexibility and business cases.

Outputs expected:

• Measurement campaign plan (data acquisition, measuring points, parameters, data quality/QA approach and on-site plan).
• Two-week 24/7 measurement dataset and reporting of results (including key assumptions and operating conditions observed during the measurement period).
• Baseline (“as-is”) total site energy balance model and energy flow analysis across the main (sub)processes and/or unit operations.

Heat recovery concept options (integrated vs coordinated systems) with a recommended configuration supported by scenario-based future energy balance comparisons including their sensitivity to future energy prices.

NetZeroCities consortium experts will be available for providing technical inputs during the project inception meeting.

Phase 2 – Electrification, flexibility (heat storage / district heating) and business case assessment

The Supplier will:

• Analyse production cycles at Alcumatic and assess how operational patterns influence energy demand, heat recovery opportunities and flexibility needs.
• Assess how heat storage solutions could enhance flexibility and improve performance of the heat recovery setup identified in Phase 1 and evaluate the implications for the business case.
• Assess how a potential district heating connection could impact the business case, based on the assumption that district heating may be rolled out to the local area (either for the existing district heating system or for the local business park only) and could function as an energy storage solution. Suppliers are expected to analyse two scenarios:
  A) base case without district heating (current condition), and
  B) scenario assuming district heating availability and/or local business park heating grid.
• Conduct an analysis of full electrification of the Powder Coating Line (approx. 180°C), including an evaluation of the business case and the maturity of available solutions.
•  For high-temperature electrification solutions, consider whether the district heating network needs to / is able to supply heat pump infrastructure (where relevant to the assessed electrification pathway).
• Develop business cases (per selected scenario and/or per standalone investment option) and calculate payback times to support investment decisions.
• Provide a recommendation on what to implement now, and—where current technology does not yet enable full electrification—outline a potential future scenario and pathway for implementation when solutions mature.

Outcomes expected:

• Analysis of production cycles and how heat storage and/or district heating connections could impact flexibility and business case outcomes.
• Assessment of full electrification of the Powder Coating Line (~180°C), including business case implications and maturity assessment of solutions.
• Business cases and payback time calculations for selected scenarios and/or individual investment cases, to be selected between supplier and City at an appropriate stage of the work.
• Recommendation on near-term implementation priorities and a potential future pathway where current technology maturity is a constraint.

Phase 2 contributes to Deliverable 2: Integrated Decarbonisation Business Case, Risk & Replication Report

Phase 3 – Development of a generic methodology for replication across SMEs

The Supplier will:

• Develop a generic, replicable methodology that can be applied to other SMEs in Sønderborg and beyond, building directly on and extracting generalisable lessons from the approach and results of the Alcumatic pilot. The methodology is expected to be concise and practical, building directly on the experience from the Alcumatic pilot rather than a fully standalone technical framework.
• Present the methodology as a clear and replicable stepwise model that guides users from data capturing through analysis and the development of scenarios.
• Ensure the methodology explicitly supports the identification of synergies between multiple processes (avoiding siloed or single-process optimisation).
• Capture and integrate learnings from the Alcumatic pilot case (including what worked well and what should be improved) to refine the quality and robustness of the methodology based on the insights gained in the Alcumatic pilot case.

Outcomes expected:

• A stepwise model/methodology that can be applied to other SMEs in Sønderborg and beyond, describing the full process from data capture, through analysis, to proposed scenarios, designed to capture synergies between processes.
• A concise set of learnings and improvements based on the pilot case, embedded into the methodology to support higher quality replication.

NetZeroCities experts will provide up to two days input to review materials to ensure the methodology is enables replicability both within Sønderborg and in other cities, and to support alignment with the wider NetZeroCities perspective and good practice. A process for coordinating between the appointed supplier and NetZeroCities will be agreed at inception stage.

Phase 3 contributes to Deliverable 2: Integrated Decarbonisation Business Case, Risk & Replication Report

Phase 4 – Technical risk (incl. fire risk) and investment decision support for the foundry context

The Supplier will:

• Assess the technical risks associated with the proposed solutions in the specific context of an aluminium foundry, with particular attention to risks linked to the ventilation system and potential fire risk.
• Carry out a structured risk analysis covering key technical constraints and failure modes that could affect feasibility, safety, operability and performance of the proposed interventions.
• Perform a sensitivity analysis on the business case(s) to show how key uncertainties and risk factors could impact investment outcomes.
• Prepare and deliver a management-focused presentation of the proposed solutions, business cases and risks to Alcumatic’s management team, aiming to support decision-making and move as close as possible toward a Final Investment Decision.

Outputs expected:

• Technical risk analysis (including fire risk in the foundry ventilation system) and sensitivity analysis of the business case(s).

Presentation package for Alcumatic management summarising proposed solutions, business cases, key risks and decision implications. Phase 4 contributes to Deliverable 2: Integrated Decarbonisation Business Case, Risk & Replication Report.

Timeline and additional information

Interested parties are invited to submit their proposals by 01 May 2026 (23:59 CET Time) to Luisa Carretti and Mateusz Hoffmann [CESF@netzerocities.eu]. Proposals should include and address all specific requirements related to the request which can be found below.