Cost effective alternatives to building energy management systems

The revolution in the student accommodation sector over the last decade has provided practically every university town with developments that offer a real home from home experience for their occupants. Draughty halls of residence with wafer thin mattresses are now few and far between. With 2.8 students vying for each room, demand is high and providers are enticing freshers with comfortable, well-appointed accommodation that includes superfast broadband, private bathrooms, their own cooking facilities, gyms, pools and even cinema rooms. To make moving in even more attractive many offer all-inclusive packages that include utility bills.

Great news for the students who don’t need to worry, at the end of the month, whether they have sufficient funds for the gas, water and electric bill. But, for an energy manager trying to balance the books, giving free reign, to a building full of students with control over their own environmental temperature, can prove to be a headache!

There are building energy management systems that provide excellent features to manage the use of energy across these types of buildings, but these call for serious capital expenditure and can be disruptive to install. Often, they are too big for the job – the proverbial sledgehammer to crack a nut. At the other end of the scale are wall heaters with built in thermostatic controls.  Most can be set and then locked, the intention being to restrict the length of time a higher temperature can be held, however, the average undergrad will soon work out or google search, that holding the button for three seconds gives them full access to ‘set the controls for the heart of the sun!’

Occupying the middle ground are intelligent thermostatic controls that are programmed locally. Most commonly they are connected to electric panel heaters or fluid-filled radiators but they can also control ‘wet’ systems.

The benefit of a thermostat that isn’t part of the heater is that they monitor temperature more accurately and the combination of a no-control heater and the thermostat is more cost effective than an integrated heater/control. An added benefit is that if either part malfunctions, only the heater or the thermostat needs replacing, as opposed to an expensive integrated unit.

Thermostats such as the ecostat2 range from Prefect controls operate the 3-stage student profile – Setback, Boost and Frost modes. Setback mode keeps the room at a predetermined temperature often 18-20°C. If the occupant requires more heat, they simply press the ‘up’ button which activates Boost mode, this raises the temperature for a set period of time, commonly 22°C for 45 minutes. When the time has elapsed, the programme reverts to Setback temperature. If the button isn’t pressed again for a set period, often 12 hours, Frost mode engages which reduces energy input but maintains the room temperature at a level that avoids frost or damp, often 10°C.

The 3-stage profile ensures energy is only used when required.

The range of thermostats includes, units for corridors or communal areas that have no user controls; units with Boost/off user control; and PIR models, which when set to absence detection will cut short the Boost mode if the occupant leaves the room during operation. All models feature open-window detection.

Heaters can only operate when fitted with the patented EnergyLock key which is supplied with the thermostat, making the system fully Lot20 compliant. A dedicated handset is used to programme the thermostats with time and temperature details. When programming is complete each unit is locked, meaning adjustments can only be made by authorised personnel.

All responsible accommodation providers are painstakingly looking at how to achieve their net-zero targets. Reviewing the control of unnecessary energy use could be the remedy for that headache.

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