Inspection of HVAC Systems through continuous monitoring and benchmarking

The iSERVcmb project is about showing the practical operation and benefits of an automatic monitoring and feedback system, as now allowed for in the recast EPBD, applied to Heating, Ventilation and Air-Conditioning (HVAC) systems in EU Member States (MS). It is an important project as previous work has indicated real savings of up to 60% are achievable in individual HVAC systems through the iSERVcmb project approach. The project is now recruiting 1600 operating HVAC systems from around Europe. It has the support of two main professional bodies for HVAC systems in Europe – CIBSE and REHVA – and eight universities across Europe, as well as input and interest from HVAC component manufacturers and property developers.

iSERVcmb builds on the results of the previous HARMONAC project, an IEE project carried out from 2007 to 2010. Its main objective was to examine and quantify the energy savings to be identified through the inspection process and provide a guideline on the cost of the inspection. 400 inspection trials and 40 more in-depth case studies were carried out – all of them available on a database. The project was able to identify and analyse 141 different Energy Conservation Opportunities (ECOs). A significant energy saving potential by system (between 10 and 50 %) was identified that could lead to considerable electricity and CO2 emission savings throughout Europe. However, one of the major findings was that many ECOs would only be identifiable through continuous monitoring. This finding led to the idea for the iSERV project. To read more about the HARMONAC project click here

Figure 1  OWS annual energy use pie chart

Figure 1 OWS annual energy use pie chart

Figure 1 shows how this metering problem manifests itself for One Wood Street in London, a modern (completed May 2008) prestige office block which is 'fully' metered to UK building regulation standards. It can be seen that, despite an apparently comprehensive metering strategy, nearly one third of the annual electrical energy use (labelled 'Balance') is unaccounted for. This building was one of the UK Case Studies in HARMONAC and was well documented, but still no-one was sure where this unaccounted energy was going. The author believes at least some of this unaccounted consumption is occurring in the HVAC system – potentially in the tertiary chilled water pumps for the chilled beams, and in the numerous fancoils in the core of the building. So, whilst HVAC systems apparently consume around one third of the annual electrical energy use in this building, it is entirely possible that their actual electrical consumption might be closer to one half of all electrical energy use in the building.

The iSERVcmb project lies on the basis that it is important that we not only understand the ranges for actual energy consumption in HVAC systems serving various end-use activities, but that we also understand the causes of variations in HVAC system energy consumption for meeting the requirements of the same end-use activities. This information will then allow more confidence in investment in improving the energy efficiency of poorer performing systems, as well as provide an understanding of how legislation should be framed to encourage better performing systems to be adopted.

"iSERV is a first attempt to provide a framework and process to address the lack of real in-use data. It is designed to produce a large dataset of sub-hourly energy use in European HVAC systems and their components. From this data, initial benchmark energy use ranges will be derived for the energy consumed by HVAC components servicing specified end-uses, areas and hours-of-use. This will enable bespoke benchmarks to be derived for actual HVAC systems servicing specified activity mixes." Dr Ian Knight, IEE iSERV Coordinator, Cardiff University, UK

For this purpose, detailed energy consumption data for up to 1600 heating, cooling and ventilation (HVAC) systems across 16+ EU Member states are collected and analysed. All data collected are sent directly to the iSERVcmb database where they remain secure and anonymous. Anonymity of end users and manufacturers is established according to the end users agreement you are requested to sign before joining, unless requested otherwise.

The aims of the iSERV project are:

  • To show the energy savings achievable from continuous monitoring and benchmarking in up to 1600 HVAC systems located in over 16 EU Member States.
  • To highlight remote data monitoring capabilities already existing and to identify new ones needed – especially for existing systems.
  • To generate benchmarks of achieved energy performance by ventilation and air-conditioning systems for specified end use activities served.
  • To show this approach is an effective complementary activity to Inspection that can reduce the overall costs of inspection to HVAC system owners (and hence the EU).
  • To show that the approach can potentially 'reward' system owners for good design, operation and maintenance of their HVAC systems by allowing them to highlight good performance in relation to specific activity-based benchmarks, and also to avoid the cost of Inspection where there is clearly no need for one.
  • To leave inspections targeted only at those installations which show poor performance or which choose not to provide this information. Both should probably expect more detailed (and therefore costly) Inspections in future.

The iSERV automatic monitoring and feedback system has already started accepting data from HVAC systems. It is intended that all actors with an interest in the energy efficient operation of HVAC systems will start seeing useful information on what helps achieve energy efficiency in practice by the Summer of 2012.  At this time we anticipate starting to see evidence of the approach achieving the 35- 40% energy savings that HARMONAC found were likely to be available for individual systems. Participation in the iSERVcmb project is free to all actors providing information and support to the project.

To learn more about how the project works watch our iSERVcmb video here or read our REHVA article exploring the iSERVcmb's approach towards achieving a better understanding of energy consumption in HVAC systems across the EU Member States.

The iSERVcm project is now looking for interested actors (owners or operators of HVAC systems, HVAC system or component manufacturers, facility managers, legislators or policymakers) to participate in the iSERVcmb project. Click here to participate