Integrated cost and energy savings
John Durbin of Daikin UK looks suggests how today’s highly sophisticated energy-efficient climate-control systems can significantly reduce whole-life costs.
When considering a building’s internal climate control, whole-life costing takes into account initial questions such as whether a new system is required or if an old system can be upgraded. Any decision will consider the costs of maintaining and operating the system, and it is also important that non-financial factors are considered. Does the equipment meet the user's technical specification? Does it meet quality standards? And is it as environmentally sustainable as possible.
It may be tempting to upgrade an existing system rather than replace it. However, today’s systems are designed to take into account a whole building’s needs, so they can achieve energy efficiencies previously unheard of. In some cases it is realistic to expect COPs of nine or even 10, so it is of paramount importance to take into account the significantly reduced running costs that a correctly designed, modern system may bring.
This approach needs to be applied at a strategic level, so it is important to consider the entire building’s heating, cooling, refrigeration and ventilation needs at the design stage.
Take, for example, a hotel. Because many service operations typically operate quite separate systems to heat and cool a building, as well as provide hot water and run refrigeration facilities, a huge amount of energy is wasted. Considering the whole building’s heating and cooling needs and delivering an integrated climate-control solution makes it possible to increase energy efficiency dramatically, thus achieving major reductions in whole-life costs.
Variable-refrigerant-flow (VRF), or variable refrigerant volume (VRV) in Daikin parlance) heat-pump technology can be used a total solution for heating, cooling, refrigeration and ventilation and can create a ‘virtuous circle’ of climate control within a building. Heat from air-conditioning systems can be recovered and used to heat hot water or over-door air curtains. It is important not to consider this approach as air conditioning with bolt-on modules but as an holistic approach to climate control that is becoming more widely recognised as an environmentally sustainable solution, as well as a way of reducing whole-life costs.
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| Heat removed from all sorts of premises such as restaurants, offices and shops by air-conditioning systems can make a major improvement to energy efficiency if it can be used to heat other parts of the building or produce domestic hot water. |
What is not so well known, however, is that it is possible to apply this same principle with refrigeration systems. Whether the building is a large hotel with refrigeration requirements for kitchens and cold stores, retail store with refrigeration display cabinets or a leisure centre with multiple uses and climate-control requirements, it is possible to use VRF/VRV technology to recover waste heat from refrigeration systems. This recovered heat can be used, for example, to supply warm air to overdoor air curtains or hot water for wash rooms.
But it is not just heat recovery that can help reduce whole-life costs. Whether a system is at the design stage or already in-situ, today’s intelligent control systems are capable of making significant energy savings (around 30% in the case of Daikin’s RTD system) for offices, shops, banks and hotels.
These flexible and intelligent systems allow a building manager to set parameters for the climate-control system, reducing the onus on a building’s users to think about energy-saving issues. For example, if intelligent controls can switch off a climate-control system when a room is unoccupied or a window or door is left open, then energy wastage is reduced automatically, without the need to monitor the behaviour of building users.
A system using PIR (passive infrared) will also be able to detect room or zone occupancy and activity levels – a particular advantage for hotel rooms, where usage can be adapted automatically when the occupant is asleep. This is hugely advantageous for building managers as the amount of energy wasted by a room occupant changing the climate control settings can be significant. The resulting energy savings will also contribute to reduced whole-life costs. Because these controls are a plug-and-play solution that simply fit onto existing systems, the cost of retrofitting them is minimal.
An additional method of reducing running costs, and therefore potentially reducing whole-life costs, is to consider using a remote monitoring service. A good remote monitoring service should be able to predict malfunctions by constantly monitoring and analysing data from equipment so that any abnormalities can be picked up at an early stage. In this way, failures can be prevented and possible downtime costs minimised.
At Daikin, we firmly believe that an integrated climate-control system should help to reduce a building’s whole life costs. Our online tool daikincity.co.uk, shows how significant energy savings can be made when a fully integrated approach to climate control system design is fully utilised.
