Targeted property maintenance – driving measurable heat network efficiency through proactive, data-led interventions

At a Glance

Across a portfolio of monitored communal heat networks, Switch2 deployed its Optimise service to identify and resolve dwelling-level inefficiencies impacting overall system performance.

Using continuous data analysis and targeted engineering interventions, Optimise delivered measurable improvements in efficiency, cost, and carbon performance, without the need for capital upgrades.

Properties targeted with Optimise visits demonstrated:

• 22% reduction in average energy consumption
• 45 % reduction in volume consumption
• 52% reduction in flow rate (l/s)
• 10% reduction in average return temperature
• 25% improvement in volume-to-energy (V2E) efficiency
• 8,124 m3 average annual volume savings per dwelling
• £406 average annual cost savings
• ~2.5 tCO2e reduction per dwelling

These results demonstrate the value of proactive, data-led maintenance compared to traditional reactive servicing models.

Importantly, these benefits were achieved without capital investment, relying instead on targeted maintenance informed by high-quality data.

Background

Communal and district heat networks depend on efficient performance at every dwelling interface. In practice, a small number of properties often drive disproportionate inefficiencies through excessive flow rates, elevated return temperatures, or poor heat transfer.

Traditional maintenance regimes, typically reactive or biennial, can allow these hidden issues to persist, increasing operational costs, carbon emissions, and system strain.

Optimise was developed to address this challenge by combining continuous monitoring with structured, targeted engineering interventions, enabling early identification and resolution of inefficiencies before they escalate.

Key Objectives

The primary objectives of the Optimise programme were to:

• Improve network efficiency by addressing high-impact dwellings
• Reduce excessive flow volumes and elevated return temperatures
• Improve volume-to-energy (V2E) performance
• Lower operational costs and carbon emissions
• Provide a scalable, preventative maintenance model for heat network operators

Assessment and Planning

Switch2 engineers used live and historical performance data to identify dwellings with abnormal operational behaviour. Key metrics analysed included:

• Energy and volume consumption
• Flow and return temperatures
• Flow rates (L/s)
• V2E efficiency indicators

This multi-metric approach ensured that site visits were prioritised where they would deliver the greatest network-wide benefit.

Optimisation Opportunities Identified

Analysis consistently showed that inefficiencies were typically driven by:

• Excessive volume movement through HIUs
• Poor heat transfer performance
• Control and valve issues causing elevated return temperatures
• Incorrect flow sensor readings
• Minor component failures with disproportionate system impact

Crucially, these issues could often be resolved through adjustment or repair rather than replacement.

Implementation and Technical Interventions

Targeted onsite interventions included:

• Valve corrections and recalibration
• Actuator and programmer replacements
• Flow sensor adjustments
• HIU control optimisation
• Bypass and control setting reviews

Each visit was supported by pre- and post-intervention analysis to verify performance improvements.

Long-Term Impact

The Optimise case study demonstrates that:

• A small number of dwellings can drive significant network inefficiency
• Early, data-led intervention delivers outsized operational and carbon benefits
• Preventative optimisation reduces reliance on reactive maintenance
• Portfolio-wide savings accumulate rapidly when high-impact issues are addressed

Optimise provides operators with a scalable, low-risk route to improving efficiency, resilience, and customer experience across heat networks of any size.

Funding and Next Steps

Optimise complements Heat Network Efficiency Scheme (HNES) studies by:

• Delivering immediate operational improvements
• Supporting evidence-based business cases for future capital investment
• Reducing short-term costs while longer-term upgrades are planned

For operators seeking continuous improvement without major disruption, Optimise offers a practical and cost-effective solution.