Hitting Net-Zero with HVAC Modelling

Improve HVAC Performance at every stage of the building life cycle

Cities around the world are implementing zero-carbon targets, some as early as 2040. Clients are demanding buildings be zero-carbon more than ever, and energy targets are being implemented to attain this. These strict targets can only be achieved if building simulation is performed throughout the entire building life cycle. Detailed ApacheHVAC modelling and analysis allows a highly accurate virtual representation of buildings and their systems. High quality modelling improves design decisions, operational efficiency, HVAC system capacity and control. This detailed approach needs to be modelled on a sub hourly basis, and model meter outputs need to directly map to the metering configurations in real-buildings, such that there can be a direct comparison of modelled and metered data.

IES Consulting are perfectly placed to take your model the next level in HVAC performance. We can represent your design and then report on plant sizing and load matching to refine performance. We can provide schematic and 3D visual representations of the HVAC's performance which provides clear communication on the opportunities and risks associated with your building. Through this approach you can be confident in unlocking the true energy consumption of the HVAC systems integrated with your building.

Loads vs HVAC modelling

Have more control over your HVAC design and more accurate results using HVAC modelling. 

  • Unlimited planty capacity
  • Static COP/SEER value
  • Fan and pump power determined by simplistic equations
  • Limited plant controls
  • Plant capacity limited to design capacity and influenced by operation conditions at each timestep
  • Performance curves reflect efficiency at varying part load and operational conditions
  • Each pump and fan invidually modelled with performance curves determining power draw as flow varies
  • Control over air and water side systems 

HVAC modelling benefits:

More control and feedback from your building toward better results

  • HVAC network represents the components of the system
  • More granularity in capturing energy use
  • Added ability to define controls
  • Greater capacity for integrating systems types
  • Capture part load performance through curves and efficiencies
  • Plant sizing moves away from rules of thumb
  • Develop flexible solutions for plant demand matching
  • Target accurate model energy predictions within 5% of real building energy

Progression of HVAC through RIBA 2020 stages

The HVAC model should be considered from Concept through to the Use RIBA stages. Make crucial design decisions, identify and assess trade-offs, meet zero-carbon targets and close the performance gap.



Stage 2 - Concept Design

  • Simple systems analysis
  • Establish how design options impact heating and cooling demand
  • Consider site opportunities for LZC/NZC design
  • Consider System types and energy source selection
Riba stage 2 concept design model

Riba stage 3 hvac



Stage 3/4 - Detailed Design

  • Identify key energy demands and explore options to reduce these
  • Identify and assess the trade-offs different design solutions offer
  • Compare the Performance of Alternative Systems
  • Develop complete HVAC model of the System Design
  • Assess Occupancy Comfort
  • Implement operational control strategies
  • Ensure Systems meet the design criteria

Riba Stage 5 Construction Model



Stage 5 - Manufacturing & Construction

  • Update HVAC model to reflect the installed plant efficiencies and capacities
  • Ensure Systems meet the design criteria



Stage 6/7 - Handover & In Use

  • Compare measured performance data to simulated performance to ensure the Building is operating as intended
  • Incorporate virtual energy sub-meters that reflect the metering configuration of the real building
  • Develop a Digital Twin of the Operational Building
Riba stage 6 in-use data

Finding detailed HVAC modelling tricky? Help is at hand! 

If you are looking to develop your skills or your project incorporates challenging design feautures then enlist the help of IES Consulting. As the expert users in applying the Virtual Environment we are best placed to share our knowledge and expertise for the benefit of your project. We offer tailored project mentoring to guide you step by step towards achieving your needs, ensuring confidence in the accuracy and delivery of the project.

Got a question?

Contact IES Consulting to find out how we can help you with your projects.