Final iSERV CIBSE workshop: The Practical Reduction of Energy Use in HVAC Systems

The final iSERV public workshop was held in cooperation with CIBSE on April 10th, 2014.

The workshop allowed participants to take a world first look at the energy end use of HVAC components in practice across the EU. The aim of the workshop was to disseminate the final iSERV project findings with regard to HVAC system inspections, energy savings, IAQ findings, case studies, processes and practices. The workshop covered the following themes:

-Inspection of HVAC Systems through continuous monitoring and benchmarking

-iSERV, Inspection and Policy

-Parallel discussions about the deployment of iSERV results

-Use of iSERV Benchmarks

-Legislating for use of Intelligent Metering.

Hywel Davies, CIBSE’s Technical Director opened the workshop and welcomed all participants. After providing the audience with a short overview of the workshop, Prof. Ian Knight, Coordinator of project iSERV explained the background of energy consumption of HVAC systems in Europe, the iSERV methodology and highlighted the outcomes and questions arising from the project. He was followed by the BRE’s Roger Hitchin, who set the iSERV project aims and outcomes against the backdrop of current inspection practices and policies in the UK..

Subsequently, two roundtable discussions took place:

1) iSERV for HVAC system operators, manufacturers and owners

Group 1 was moderated by Prof. Ian Knight and was given a detailed presentation of the iSERV reports provided to end users participating to the project. Participants were primarily interested in the type and variety of benchmarks produced by the iSERV approach, the use of the building’s fabric and solar gain in the calculation of the benchmarks, the compatibility of building description data from other sources to the iSERV spreadsheet and the content of the iSERV reports. The topics that were discussed are presented in detail below:

Question from the audience:Can iSERV produce benchmarks that are more popular in commercial buildings:

•Energy use against occupancy

•Energy use against rental price sqm

•Energy use against G.I.A.

Response:The iSERV platform has the ability to produce these benchmarks. However this will require end users to provide more data about their buildings. In the life span of the project, we chose to restrict the amount of information required from the end users to the process of describing their building as a structure of spaces, HVAC systems and components. We hope that the iSERV benchmarks will act as a starting point to further discussion with stakeholders and project work that will allow for the production of additional benchmarks.

Question from the audience:Do the iSERV benchmarks and reports take into consideration the building fabric and solar gains?

Response:Within iSERV there is an allowance for gathering more information about outside conditions from internal building sensors in order to calculate energy signatures but the project deliberately does not consider fabric explicitly due to the unacceptable data demands this would impose during the project. Within iSERV the building fabric is treated as part of the Energy Conservation Opportunities. It is possible for iSERV to evolve to consider fabric issues if needed, initially by using assumptions regarding the building fabric based on the location, type and construction year of the examined building.

Question from the audience:Can iSERV provide conclusions on the range of savings deriving from oversized plants?

Response:iSERV is currently reporting electrical energy savings of up to 60% in individual systems and 5 – 33% were expected on average. Those savings have derived from understanding the building and improving system control. We do not aim at identifying oversized plants as something that is a bad approach; we are looking at producing ranges of what systems consume without differentiating between oversized and non-oversized plants. However, where installed load data is provided, we can examine the relationship between installed load, power demand and energy use.

Question from the audience:Going beyond legislative frameworks, what is the vision in using the information produced in the iSERV project?

Response:iSERV is hoping to contribute towards establishing standards regarding the collection and use of building services data. In particular, it hopes to provide an online benchmarking resource for such data which will be continually updated.

Question from the audience:Is there a way to automatically import building description data from to other platforms (e.g. BIM, TM22) to the iSERV spreadsheet?

Response:Although we recognise that such a feature would help in reducing the time and effort needed to fill the iSERV spreadsheet for those who do have building description data in other formats, this has not been part of the project’s scope. We hope that the iSERV findings with regard to building data collection and quality will contribute to the creation of relevant standards to reduce such hurdles.

Question from the audience:Does iSERV allow for the calculation of costs from operating specific HVAC components?

Response:The iSERV platform can provide end users with HVAC components running costs as long as the end user can provide a tariff unit.

Question from the audience:What are the expected typical costs to describe a building using the iSERV spreadsheet?

Response:The iSERV spreadsheet is an asset register that can be viewed as a time and cost investment. We have calculated a conservative cost of filling out the iSERV spreadsheet of approximately €1/m2 based on observations during iSERV.

Question from the audience:From the perspective of conducting inspections, how does the iSERV spreadsheet compare to TM44?

Response:The iSERV spreadsheet can be used as a detailed asset register to support TM44 requirements during inspections.

Question from the audience:What do the iSERV reports consist of?

Response:There are a number of standard reports contained within the HERO database. If these are not sufficient then bespoke reports can be designed according to the end user needs by logging into the HERO database and selecting the information to be included.

2) iSERV for legislators, policy makers, professional bodies & associations

Group 2 was led through the discussion by Roger Hitchin. The group agreed that the financial advantages of energy efficiency are valuable to all stakeholders; however if incentives were available in order to push end users to introduce more energy efficient measures, some inspector’s neutrality could be questionable by dint of financial reward. Moreover, participants suggested that the information deriving from inspections tends to be too technical for certain audiences. It was pointed out the iSERV approach shows savings to end users in a clear and understandable way that allows them to embrace it as they start to understand their buildings better.

Some participants proposed the iSERV method to be rolled out nationally in schools amongst which many have BMS or metering but no means of analysing the metered data. The iSERV approach could be applied not just for air conditioning but for all energy and water usage, benchmarked by type of school, as this could become a good transparent tool for bursars. For this to be achieved, participants agreed that it is crucial for BMS data to be compatible to the iSERV spreadsheet.

Overall the group concluded that the iSERV spreadsheet would be invaluable despite having to be completed by or with the help of a competent person and should expand to include more detailed lighting description, water usage etc. Most importantly, for an iSERV type of approach to become more popular there is a need for metered data to exist in open protocol and BMS terminology should be standardized.

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