Summer arrives, the weather warms, flowers bloom, all is good with the world!

But, for students in our universities, it’s exam season mid-May to mid-June. Four weeks of cramming. Then, Relax! Nothing more can be done. Pack the car, and head off for a well-deserved break, away from it all. A long summer to recover, before for some, it will all begin again in September.

While there are no students around, accommodation providers take the opportunity to deep clean, maintain and refurbish their properties.

There are close to 1.7million rooms nationwide, a formidable community. Spread across the country, they number a population twice that of Birmingham.

It takes a lot of energy to maintain comfortable environments for this many rooms, and the pressure on providers to meet net-zero and decarbonisation targets is immense.

The burning issue is that generally, the people consuming the energy are not directly responsible for paying the bill. In my experience this is apparent in the way the temperature of rooms is regulated. With little or no control on many heaters, the thermostat is set to maximum, where it will remain all year. Should it become too hot, the window is opened for airflow while ‘the heater rotates the meter’!

For Energy Managers this is frustrating, to say the least. The budget for energy use is their responsibility but they have no control over consumption.

I was particularly excited a few weeks ago, when a customer shared with me data showing energy use from 2017 to present day. It was interesting because UWE had installed a Building Energy Management System during the pandemic. The reason for my excitement is that it showed ‘before and after data’ which is very difficult to come by as a third party.

The BeMS replaced a reasonable control system that had been installed when the campus was built in 2006, but fresh pressure, on reduction of energy use, led to a search for even greater control, hence the Irus installation.

With a cursory glance, the figures told a predictable story of month-on-month energy savings.

Digging deeper into the heating season of October to March, I took a 3-year average consumption, 2017-2019, to mitigate for unusual weather peaks and troughs. I then compared this with 2022, (ignoring 2021 as it was disrupted by lockdowns and unusual occupancy patterns). The total reduction is 22%. Project this forward to the coming year, with a tariff of 16.5 pence per kWh, and this amounts to a significant £147,819.


The total reduction is 22%. Project this forward to the coming year, with a tariff of 16.5 pence per kWh, and this amounts to a significant £147,819.


Savings can be attributed to PIR detection of occupier absence from rooms and the reduction of input when windows are opened. If the control that was replaced hadn’t had the pre-set 45-minute boost button time feature, I estimate the saving would have been closer to 30%.

But the surprising element that emerged from this complete dataset was what happened in the non-heating season, specifically May through August. During this 4-month period, the weather is warmer, and less heating is required. The occupation of rooms is greatly reduced due to the summer holidays and a lot of rooms being empty for most of June-September.

Compare summer consumption (2017-19) with 2022 and worst case 45,476kWh, and best case, 72,346 kWh of completely unnecessary energy use was avoided.

Most attention is rightly focussed on the autumn and winter seasons, but it pays dividends to be aware of energy being used during warmer months. With a centrally controlled system that is easy to universally adjust, summer profiles can be tweaked, resulting in even greater savings.