TM54 - Operational Energy Analysis

The TM54 assessment sets out a detailed methodology to calculate and evaluate operational energy use at the design/feasibility stage. The methodology uses dynamic modelling to reliably estimate energy use for heating, cooling, fans, and pumps alongside the use of more realistic occupancy profiles.

Within the industry, there is a growing awareness buildings constructed to today’s energy efficient standards use more energy than designers and occupiers thought they would. With increased energy costs and the desire for businesses to reduce their carbon footprint, building stocks that don’t meet expectations can incur significant costs and hamper organisations sustainability initiatives.

This discrepancy between modelled performance and actual performance is known as the ‘performance gap’ and there are two main reasons for this gap. The first being what is and isn’t assessed for the purpose of compliance with the building regulations. For building compliance, only space and water heating, lighting and ventilation consumption are assessed. Energy consumption from items such as TVs, cooking, white goods, and personal devices are not included. In non-domestic settings, electrical equipment, lifts, catering facilities and server rooms would not be included in compliance assessments.

The second reason for the performance gap is related to site practice. This can be both during the build and once the building is in use. If detailing hasn’t been followed or has been poorly constructed, this can have a significant impact on the performance of a building. If mechanical services have not been appropriately commissioned or installed and the building occupier has not been adequality trained, these services are likely to work inefficiently.

What are the benefits of completing a TM54 assessment?

  • By Creating a dynamic thermal model of your building, you can review the proposed design against any operational energy targets e.g predicted fuel costs.
  • Demonstrate different scenarios a building may be used for, and it’s predicted energy consumption e.g weekday and weekend energy consumptions
  • Provide the design team with a breakdown of your buildings most energy intensive activities thus allowing for opportunities to reduce energy consumption in these areas.
  • Scenario planning for different building usage.
  • Assisting with feasibility studies and operational budgets during the early conception stage.