Accurate measurement brings just rewards

Trevor S. Palmer, Managing Director at Sontay, examines the important role that metering has to play in reducing carbon emissions in commercial buildings.

Building owners are under intense pressure to save energy and reduce carbon emissions.

Government legislation and incentives are driving through changes in building practices and technologies to ensure that the UK meets its 34% emissions cut on 1990 levels by 2020 which is required under the Kyoto Agreement.

Targets for all new buildings to become carbon neutral represent an important stepping stone on this path. New schools face a 2016 deadline, public sector non-dwellings are required to become zero carbon by 2018 and other non-dwellings, such as hotels, will need to comply by 2019. 

With energy costs rising, it’s clear too that financial pressures are playing a part in greening our building stock. It’s self evident that a more fuel efficient solution will help reduce running costs for building owners and their occupiers.

However, whilst the buildings themselves may be constructed with impeccable low or zero carbon credentials, they are still occupied by people. And, ultimately, it is the variable lifestyles and habits of the occupants who will determine if the building is energy efficient or not.

Real time savings

Knowledge is power. The Government itself recognises this fact.  Soon after coming to power, the Prime Minister announced that in its bid to be the greenest government ever and cut carbon emissions by 10% within 12 months, real time reporting of energy efficiency data would be implemented across 19 ministerial HQ buildings. This information can even be tracked by the public online to ensure that government is, in its own words: “Improving the energy efficiency of its operations as well as providing transparent evidence on progress”. These real time energy meters help departments identify when and where energy is being used and assist them in trying and finding ways to reduce that energy use.

Better metering is a significant component in the Carbon Reduction Commitment Efficiency Scheme (CRC) introduced by Government in 2008 which aims to drive cost effective carbon emissions reductions through greater energy efficiency. The CRC is aimed at large non energy intensive organisations, such as, supermarkets, retail chains, hotel chains, large offices, small to medium industrial facilities, and almost all public sector organisations which in total account for 14 million tonnes of carbon (MtC), nearly 10% of the UK’s total annual carbon emissions. According to DECC, the CRC will save 1.2MtC per year by 2020 from this sector. The better an organisation performs in terms of cutting its emissions, the higher it will appear in the annual performance league table.

Participating in the CRC demands that organisations measure the energy they use. Under the CRC, electricity and gas supplies will be considered as either a core supply or residual supply, based on the meter that measures the quantity supplied to each organisation. The scheme offers guidance on different meter types and explains how to collect the required data from them.

As a result, metering and sub-metering equipment are now placed firmly at the heart of our drive to reduce carbon emissions. In practice, there is still some way to go for organisations to monitor the energy they use. The first CRC performance league tables just published by the Environment Agency show a huge variation in performance between the best and the worst organisations. They indicate that over 60% of more than 2000 organisations have taken action by installing smart meters and obtaining a certificate for good energy management from the Carbon Trust or other accreditation scheme. But the remaining organisations in the table did not score any points which suggests that they are not even monitoring their energy data.

Monitor energy data

For those companies seeking help in complying with the obligations of the CRC and improving their energy efficiency, then Sontay can help. Our extensive range of meters includes flow sensors, ultrasonic flow sensors, water meters, compact heat meters and heat meter integrators conforming fully to the requirements of the Measuring Instrument Directive (MID) and EN 1434, where applicable.

Accuracy, reliability and versatility are important factors in choosing the right meter for an application, and making sure that the collected data is in itself, providing a robust measure.

Our heat meter integrators feature the latest technology to calculate heat usage from heating and cooling systems. The dynamic measuring cycle enables even the smallest energy consumption to be reliably collected. Permanently showing the total heat consumption, the large, multifunction display can also reveal all data collected.

A compact version of the heat meter is also available for smaller applications and includes the flow meter and calculator. These Heat Meter Integrators and Compact Heat Meters are compatible with Sontay’s M-Bus network which allows up to 250 metering devices to be cost-effectively connected to an M-Bus Master device so that metering data can be quickly and easily accessed via a PC.

Alternatively, to measure volumetric flow in hot water heating systems, single-jet flow sensors, multi-jet flow sensors and flanged flow sensors can guarantee long term measuring stability and high reliability, operating at up to 120?C with a safety margin of 130?C. These sensors can be used with chemically treated water and continuous flow conditions and, depending on the model selected, are versatile enough to be installed horizontally or vertically to suit different measuring requirements. 

Ultrasonic flow sensors, meanwhile, have no moving parts and are virtually silent in operation. They measure the flow by using the transit time principle – one ultrasonic signal is launched in the flow direction and one against the flow direction. The flow rate is concluded by the delay time measured and the information is then transmitted to the calculator by the way of electronic pulses. The calculator then uses the latest innovative technology to calculate heat usage from heating systems for easy access and display. Flow sensors for heating can be used with chemically treated water and are designed for continuously or very high duty, cycle flow conditions.

Value for money

Selecting the appropriate meter for an application is one thing, achieving best value for money quite another. Choosing what appears to be the cheapest metering option on paper can quickly prove to be a false economy, especially for an organisation participating in the CRC scheme. If the meter fails to perform reliably, then not only will the collection of energy data itself be compromised, but problems will escalate elsewhere. Add in the cost of service visits and the downtime if a heating system needs to be drained to enable a repair and making an investment in metering gets even more complicated.

Also take account of the requirement for software upgrading, meter changeovers and programming which typically occur in metering installations, and you can see that technical support and the level of service back-up are equally important factors in the whole value for money assessment. Regrettably, these are areas often given far too little attention by metering manufacturers and suppliers. 

Metering is often seen as something of a dark art. It shouldn’t be that way. Be involved in your choice of product, be critical of what your supplier tells you, and ask questions about the customer service that they will provide to support equipment specification. Choosing the right metering products, and the right supplier, will not only ensure costs are kept down but that your HVAC system can be measured effectively, allow
ing organisations to meet their carbon reduction commitments, cut fuel bills and dramatically improve their energy efficiency.

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