Keeping cool about energy

31 August 2012

Tim Fryer asked a number of organisations what were the considerations involved in running and specifying HVAC. In general the answer had little to do with creating the right office environment. Of far more importance was how much energy the system used.

Setting the tone was Sue Sharp the newly elected president of the B&ES (Building & Engineering Services Association – formerly the Heating and Ventilating Contractors’ Association). “The wider use of Display Energy Certificates (DECs) will make it easier for FMs to see exactly how their buildings are performing,” said Sharp.

DECs will be required in all buildings over 500m2 by 2013 and those over 250m2 by 2015 under the requirements of the recast Energy Performance of Buildings Directive (EPBD), which came into force in February this year.

“This has major implications for all commercial building owners as they will have very clear and transparent energy goals to meet,” said Sharp. “They will be able to see exactly how much energy they are wasting and, with energy costs steadily rising, this will become a clear business priority. If you can measure your energy use you can also do something about it – as long as you know ‘a man who can’ i.e. a building engineering services contractor with the right set of skills.”

Sharp believes that the visibility of energy data will only add to clients’ determination to bear down on operating costs and, while “most people would state publicly that saving carbon emissions and cutting environmental impact is important, they realise that finance is now the main driver for better buildings”.

“With the advent of performance guarantee contracts, either directly or indirectly through initiatives like the Green Deal, delivering on a building’s operational promise becomes a financial imperative,’ claimed Sharp. She was also keen to highlight the Renewable Heat Incentive (RHI) as another case where technologies must deliver on their design promise.

“That puts pressure on FMs to understand how systems are set up and controlled. They should seek operational guidance from their contractors. RHI payments are dependent on readings from the heat meters installed with every project. The amount of heat generated will be continually measured and monitored – and if they don’t deliver the RHI payments won’t materialise,” explained Sharp.

Seasonal Energy Efficiency Ratio

Graham Wright, Legislation Specialist at Daikin UK, explained how another aspect of legislation is going to impact on selection of new systems. He commented: “From 2013, air conditioning systems below 12kW will have to meet new energy efficiency standards and be labelled accordingly, under the Energy Related Products Directive (ErP). Facilities managers will need to be aware of the implications of this new legislation because it will affect which systems can be specified.”

At the heart of the new legislation are changes to the way in which energy efficiency is measured. The existing nominal ratings, Energy Efficiency Ratio (EER) for cooling and Coefficient Of Performance (COP) for heating are being replaced with two new measures: the Seasonal Energy Efficiency Ratio (SEER) and the Seasonal Coefficient Of Performance (SCOP).

Wright continued: “Until now, air conditioning systems have been designed to reflect the best performance at nominal temperatures of 35°C and 7°C and are at their most efficient when operating at full load, not in partial load, which is more realistic for northern Europe. The new measures also factor in the energy consumption of products in auxiliary modes such as standby or off mode, or when the thermostat is off. While these factors reduce the apparent energy efficiency of the product, as a result the SEER and SCOP ratings are a more accurate reflection of real life energy performance than the previous nominal system.

“These changes are reflected in the redesigned energy labels. Previously, labels only had to show cooling EER and energy consumption, while now they must show SEER, SCOP and energy consumption in both heating and cooling modes. While next year’s legislation only affects smaller and light commercial systems, consultation is already underway on minimum energy efficiency requirements for systems over 12kW.

Acceptable energy efficiency thresholds will tighten further in 2014. So it is clear that forward thinking facilities managers should stay ahead of the trend and select seasonally efficient air conditioning systems not only to meet forthcoming legislation but also to reduce energy consumption and running costs.”

Maintenance

Of course legislation may impact on the nature of new HVAC systems bought, but just as important is making sure that exisiting systems are operating efficiently. Aneysha Minocha, Energy Services Director, GSH Group, said: “As a consequence of the global economic slowdown some organisations are being forced into reducing their maintenance and refurbishment budgets. This can have a significant impact on a building’s performance, energy usage, asset reliability and subsequently business continuity and, most importantly, end-user convenience. Whilst short-term economic gain can be quickly achieved there is no doubt that it may compromise long-term value to the business. There is a fine balance that needs to be achieved between maximising the life of existing assets and upgrading to energy efficient equipment whilst ensuring budgetary compliance and business continuity.

“One way to address this is to intelligently sweat the assets, avoiding changes and upgrades whilst ensuring the highest possible asset efficiency and reliability. Further, this balance can be addressed whilst operating within cost constraints by capitalising on synergies that may exist between various operational budgets such as Capital Replacement, Energy/Utility and Planned Maintenance/Compliance.

“However, the ability to monitor and promptly affect change is critical to the success of this Energy-Lead diagnostic approach which optimises the energy efficiency and lifecycle of key assets. This is not to be confused with reduced maintenance regimes which, if simply implemented, could impact business continuity. This approach requires Stakeholder engagement across the organisation to align all the different agendas, detailed Asset Analysis and an Investment Appraisal to ensure asset longevity, efficiency and reliability.”

Keep it under control

Lisa Gingell, director t-mac Technologies Ltd, believes there are basic ways of managing equipment that will affect its efficiency: “It’s clear that the inefficient use of HVAC and poorly performing or faulty equipment can have a significant impact on a building's energy consumption and ultimately the company's bottom line. For example, by leaving air-conditioning and heating on at the same time effectively cancels the two systems out, wasting a significant amount of energy and money in the process.

“Metering plays a key part in energy management legislation. Building managers either manually act upon metering data, or implement a Building Management System (BMS) for better control. However it is important to remember that BMS hardware alone was not originally created with energy in mind,” continued Gingell.

“In today’s economic climate, control systems are crucial for businesses to cut excess energy usage which can have a major impact on reducing a company’s bottom line. It is no longer just about controlling the building’s plant and operations anymore. To keep up with legislation, energy efficiency measures need to also include other independent systems, such as split air conditioning units, heating and ventilation as well as kitchen extracts, fans and, boilers and lighting. Today, energy has formed a significant part in building considerations and has thus led to the birth of the Building Energy Management System, or BeMS.

“For effective BeMS, the hardware needs to work in harmony with the software, be easy to use and maintain a focus on understanding energy use. Businesses need to implement the correct controls for the building, yes, but cross referencing against the other energy management activities of the organisation is paramount. Without this consideration, a BMS will never reach its potential as a BeMS”.

But what if your new HVAC system suffers delivery delays or an existing system breaks down? Russell Wilson, Director of Cool Energy, explained there are circumstances when FMs can look to a rental solution to a short-term problem.

“We have recently worked on an increasing number of facility projects for building refurbishments where hot water/heating and air conditioning systems are replaced for new in hospitals, offices, local council projects and server rooms (including close control). We’ve found that our customers are looking for a fast response to minimise any site disruption as new equipment can often come with long lead times, or breakdowns can cause unexpected disruption,” commented Wilson. “Moving aside from HVAC chillers, for sites with existing cooling towers legislation states that they require annual maintenance and thorough cleaning. Rental systems can be provided to oversee these periods to prevent any downtime in operation.

And finally….
And as an afterthought, is air conditioning always the only answer – can a simple fan do the job? Fantasia Ceiling Fans claim: “Air conditioning can be very expensive to run, using large amounts of electricity, but low energy fans can be run on low speed for eight hours a day, every day of the year for as little as around £10 per annum. Running a 1100 watt air conditioning unit is likely to consume around 30 times more power than running a DC motor ceiling fan on high speed.

“In addition, people who spend long periods of time in an air conditioned atmosphere, such as an office, often complain that it aggravates respiratory ailments like asthma and tightness of the chest. Using ceiling fans does not provoke such health problems, and many people prefer the use of fans, seeing them as a more natural way to keep cool.”

Everyone’s opinion, whatever their interest in HVAC, revolved around one basic point – being cool is all about energy.