KZENON / SHUTTERSTOCK
SHUTTERSTOCK
MONITORING HVAC SYSTEMS
Research has shown that metering and monitoring HVAC systems can lead to substantial savings in energy use at little capital cost. Now a new project is inviting hundreds of organisations to participate for free in a major pan- European study to demonstrate the benefits of automatic monitoring when used to complement statutory HVAC inspections. Alex Smith reports
WARNING SYSTEM
EARLY
It’s a no-brainer. To achieve the energy savings you usually just need a regular update of the systems’ performance to prevent them drifting out of control Ian Knight
A
Cardiff University administrative building has slashed the energy used by HVAC systems through the use of metering and
monitoring. By analysing the performance of its HVAC system, the energy managers at McKenzie House were able to identify HVAC energy saving measures that amounted to a 25% saving in the building’s total annual electricity bill. McKenzie house was part of an EU-
funded project called HARMONAC, which monitored and assessed the performance of 42 HVAC systems across Europe to assess their performance and identify energy conservation opportunities (ECOs). Now the research team is inviting building
owners and managers to participate in a new EU-funded project called iSERVcmb that could help see reductions in HVAC energy bills by up to 60%. iSERVcmb, in which CIBSE is a full partner, aims to collect sub-metering data from 1,600 HVAC systems in the EU. It will analyse and compare this information to enable the benchmarking of individual
www.cibsejournal.com
HVAC systems within buildings. From these benchmarks building managers can identify the measures required to save energy in the specific HVAC system configurations that are servicing the activities in their buildings. iSERVcmb will show whether automatic monitoring would offer a better alternative to the inspection of air conditioning systems across the EU, or whether it could be used to complement current statutory inspections. Regular inspection of air conditioning systems with rated output of more than 12KW was required under the Energy Performance of Buildings Directive, but following the findings from HARMONAC automatic monitoring and feedback systems can now be used to reduce the frequency of testing under the recast EPBD. HVAC systems account for 11% of all electricity consumption in Europe according to the EC’s Joint Research Centre. For the EU to meet its target of reducing energy use by 20% by 2020, it must do something to ensure these systems are energy efficient. There is little information in the public
January 2013 CIBSE Journal 59
OPINION
Your letters
often determine most – or all – of the measures that should be undertaken, without the time and expense of metering and monitoring. The CBECS database in the US has
end-use energy data for most building types, and serves as the benchmark for programs like Energy Star. However, with my experience installing and monitoring thousands of submeters of all types over many years, it is essential to recognise the human and capital expenses involved, both initial and ongoing. Depending on the meter type,
This month: Calculated vs actual CHP district heating performance, and the ‘benefi ts’ of energy monitoring
Calculated performance There have been many discussions about the benefi ts of combined heat and power and district heating. The energy benefi ts are stated on the basis of calculated performance. As we know from building performance, this is often very wrong compared to the measured data. To avoid this mismatch between the calculated and the actual, I suggest that the heat providers publish and label the energy content of the delivered heat. For each kWh of heat sold to a customer, it should be clear how much fuel was actually used, be it electricity, gas, oil, coal, wood or refuse; and, if the system was used to make electricity, how many kWhs were exported. This information is certainly
known by the providers of the heat, so they should be able to publish results from previous years. This data will create a much needed evidence base for the discussions on the provision of heat in the UK. Bill Watts FCIBSE Partner of Max Fordham llp
16 CIBSE Journal April 2013
Overstating the case? In the CIBSE Journal’s January 2013 article headlined: ‘Early warning system’, it overstates the benefi ts and understates the costs of metering and monitoring to reduce energy consumption in buildings. No specifi c examples are provided with data. One can readily determine the potential for energy savings for almost any building by looking at the total building’s metered energy data. If the consumption, or cost per unit area, is higher than the norm for that building type, there is great potential for reductions. If the consumption or cost per unit area is lower than the norm, there is little potential for reductions. This simple determination is quick and easy and, for most buildings, does not cost anything. If the
consumption is higher than the norm, then a trained and experienced engineer can
It is essential to recognise the human and capital expenses involved in monitoring
and whether it’s in a new or existing building, the initial cost usually exceeds £1,000 per meter, but can often be thousands of pounds per meter. The quality and reliability of meters used is often not known. I have some cases where the monthly energy cost per meter is only a few pounds, so the capital cost can never be recovered. Having an experienced engineer
to examine 1) the data; 2) the energy using systems; and 3) the use and occupancy of the spaces served is vital, and not something a spreadsheet template alone can accomplish. The capital cost of making any changes, along with the potential savings, may not justify implementation. Plus there is the ongoing cost
of operating and maintaining 1) the measure itself; 2) the metering systems; and 3) monitoring the data. Eur Ing Int PE Larry Spielvogel PE CEng FASHRAE FCIBSE FSLL Consulting Engineer
CIBSE Journal welcomes article proposals from any reader, wherever you are – whether it be letters, longer opinion pieces, news stories, people or events listings, humorous items, or any ideas for possible articles.
Please send all letters and any other items for possible publication in the CIBSE Journal to:
editor@cibsejournal.com, or write to Alex Smith, editor, CIBSE Journal, CPL, 275 Newmarket Road, Cambridge, CB5 8JE, UK. We reserve the right to edit all letters. Please indicate how you wish your letter to be attributed, and whether you wish to have your contact details included.
www.cibsejournal.com
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60