Gas and electricity prices have exploded due to the energy crisis. Even the VUB cannot avoid tightening its belt to pay its energy bills. Julien Blondeau knows how to keep your energy consumption under control, both for an organisation and an employee. He is an energy expert at the Thermodynamics and Fluid Mechanics Group research group at VUB, and the Joint Research Groupe BRITE (Brussels Institute for Thermal-fluid systems and clean Energy) at VUB-ULB . "It is painful, but it is also a great opportunity to learn to use energy more sustainably," he said.

While studying civil engineering, Julien Blondeau was fascinated by thermodynamics, the science of energy conversions. "I was able to apply this science in industry before becoming a professor. I can now pass on that practical experience to the university. Thermodynamics has a lot of concrete, technical impact on energy generation, but it also asks a lot of philosophical questions, which I find even more fascinating."

In his research group, they are engaged in research projects on renewable energy, among other things. "I myself mainly study the sustainable production of heat and electricity, for example using green fuels such as hydrogen or biomass, and the optimal development of heat networks."

What can we as employees do to bring down costs for the VUB?

"It is the fastest way for an organisation to save on energy: encourage employees to adjust their behaviour. First of all, we can already turn down the thermostat. That quickly saves five to 10 per cent in costs per degree. How much exactly, depends on the building and the outside temperature."

"They are small actions that can save you a lot in total. Closing taps properly. Don't use lights and heating when not needed. When you ventilate the room: heating off. Doors closed. Turn off appliances. And a smart one: work all together in 1 classroom. Preferably in as small a room as possible."

"Of course, as an organisation you should then also turn down the heating centrally, at least if you also heat centrally."

"Together, you can then cut back considerably on heating. It won't save the world, but at least 10 to 15 per cent savings should be possible. Especially in older buildings, heating takes up a large part of energy costs."

Of course, you also need to keep the heat inside.

"Then it's all about insulation. For that, in practice, it makes a lot of difference whether you heat an old or new building. Old buildings are often lousy insulated. In new buildings, heat production accounts for only 20 per cent of total energy consumption due to poor insulation. At home in a - often older - private house, the figure is much higher, around sixty-seventy per cent. For the VUB, I estimate that at least half of the total energy consumption serves to heat the buildings. Because energy bills are so high now, as an institute you won't be eager to invest. But putting money into thermal insulation certainly pays off in the long run."

It's 2022: can modern technology also contribute?

"That brings us to smart appliances: sensors, timers, LED lighting, thermostatic taps. There is indeed a lot to gain from these. Especially if you apply them correctly. Take wireless and mobile thermostats, for example, you have to be very deliberate about placing them in the right places. Namely, where work is done such as in a lab, and not in the mess hall or corridor."

Energy bills are already high, but can additional investments on top of that now pay off?

"Many small investments can add up to quite a lot. Require departments to buy more modern, sustainable appliances. Green refrigerators, dishwashers, printers, PC/s with an A-label already make money. The purchase price should not be the only deciding factor. So trade in that noisy, dirty table frigo for a new, fuel-efficient fridge. With that, you can also get rid of eco-cheques nicely. There will be plenty of people in the team who don't know what to do with eco-vouchers."

 "Precisely because the energy bill is paid centrally, there are often not enough incentives for the employee to think about this and make the right decision. So while there is none: do it for the VUB and the environment! It saves our university a significant amount of energy."

We also have special locations at the uni.

"We have very specific situations, such as a swimming pool and labs. Of course, a swimming pool always has a peppery bill, because those huge amounts of water have to be heated and filtered. You can't stop for a weekend with that. In fact, starting up again takes a lot of time and energy. What you can do in a swimming pool and in all sports facilities, however, is turn off the hot water for the showers when they are not being used, for instance at night. The hot water for the showers can be turned off when the sports facilities are not being used. And the temperature can go down, maybe even off. You can sport yourself warm, though.

"The labs are another story. There is a lot to gain there too. An energy expert can do a scan to see whether a lab is being heated efficiently and whether the equipment there is still energy efficient. That can yield a lot.

Wouldn't it be better to send all employees home to work there?

"That would be a bit cynical. Because then you turn the costs on the employees. At home, you turn on the stove too. But on the other hand: in the current situation, many people already work at home several days a week. So if you agree on some fixed days for working from home, you can turn down the heating at universities considerably on those days.

Getting through this autumn and winter will not be easy

"It is painful, but it is also a great opportunity to learn to use energy more sustainably. Even without this huge price hike, we need to learn to use energy differently. Mankind is carelessly using raw materials and plundering our planet, with all the consequences that entails. Besides innovations around energy production and the smart use of renewable energy sources - solar, wind, biomass, hydropower, etc. - reducing our energy consumption is the best way to leave the world in a clean way for the next generation."