For many housing associations and property owners, energy optimisation has gone from being a technical detail to a central part of the property's finances. As district heating prices rise, operating costs grow and energy-efficiency requirements sharpen, it is no longer enough to react only when something feels wrong. The property needs to be followed up, controlled and optimised continuously.
That applies to the heating system above all. A badly set heating curve, an unnecessarily high supply temperature or large temperature differences between apartments can quickly become expensive for an association. At the same time, residents want an even and comfortable indoor climate. Nobody wants to pay for overheated apartments, but nobody wants to freeze either.
This is where energy optimisation makes the biggest difference. With PropSaver, Nordic Propeye's solution for energy optimisation, we help housing associations and property owners use heat more precisely through smart control, indoor sensors and digital follow-up. The goal is the right temperature with less unnecessary energy use.
What is energy optimisation?
Energy optimisation means that the property's energy systems are adjusted, controlled and followed up so that energy is used as efficiently as possible. In a multi-dwelling building this often covers heating, ventilation, hot water and common electricity, but for most associations the heating system is the biggest and most pressing issue.
A common misconception is that energy optimisation is just about lowering the temperature. It is not. Done right, energy optimisation is about giving the building the right amount of energy at the right time, based on actual data from the building.
That can mean the heating system takes into account, for example:
- the current indoor temperature in different parts of the property
- outdoor temperature and weather forecasts
- solar gain and wind
- how quickly the building responds to temperature changes
- differences between apartments, floors and facades
- how the heating curve, supply temperature and flows are set
The Swedish Energy Agency describes operational measures in multi-dwelling buildings as continuous work, where existing heating and ventilation systems need to be correctly set for the building's conditions and the residents' needs. That is also where many associations have the greatest potential: not necessarily in major rebuilds, but in better measurement, control and follow-up of the systems already in place.
Energy optimisation and energy efficiency: what is the difference?
The two terms are often used together, but they do not mean quite the same thing.
Energy efficiency is the broader concept. It can cover larger technical measures such as additional insulation, window replacement, ventilation work, heat pump installations or other investments that reduce the building's energy demand.
Energy optimisation sits closer to daily operations. It is about making existing systems work smarter through better data, better control and continuous follow-up.
For an association, energy optimisation can therefore be a natural first step in a larger energy-efficiency effort. Before making big investments, it pays to know how the building actually behaves. Where is the building running too warm? Where do comfort problems arise? How does the building respond to cold, sun and wind? Which settings drive unnecessarily high energy use?
With the right data it becomes easier to prioritise the right measures, and to avoid spending money on the wrong things.
Why has energy optimisation become so important for associations?
The short answer: heat has become a bigger and bigger cost issue.
According to the Nils Holgersson report on district heating 2025, district heating prices rose by an average of 9.2 percent between 2024 and 2025. That followed a 15.2 percent increase in 2024 and 7.8 percent in 2023.
For housing associations, this means heating has a growing impact on monthly fees, maintenance plans and long-term finances. Even modest percentage savings have a large effect when applied to one of the property's biggest operating costs.
At the same time, buildings account for a large share of Sweden's energy use. Boverket notes that the construction and property sector accounts for a significant share of the country's energy use, with heating as a central item. In multi-dwelling buildings, district heating is also the dominant form of heating.
That makes the heating system one of the most relevant places to start when an association wants to cut its energy costs.
The problem with traditional heating control
In many multi-dwelling buildings, the heating system is still controlled primarily by the outdoor temperature. The system reads how cold it is outside and sends out heat according to a preset heating curve.
That can work reasonably in theory, but in practice buildings are more complex.
Two apartments in the same building can have completely different conditions. A corner apartment can get colder when the wind blows. An apartment with large south-facing windows can be warmed by the sun even on a cold winter day. An older building can have a wider temperature spread between apartments, while a newer one can retain heat longer than the control system expects.
If the heating system only considers the outdoor temperature, it misses what is actually happening inside the building. The system then risks sending out more heat than the building needs. That leads to unnecessarily high heating costs, while some residents may still feel the temperature is not right.
That is why a heating system needs more signals than just the weather outside the facade. It needs to understand the building's actual indoor climate.
How smart energy optimisation works in practice
The foundation of smart energy optimisation is to measure, analyse and control. Only with reliable data from the building can you understand what needs adjusting.
With temperature sensors in apartments and common areas, owners and boards get a clearer picture of the indoor climate. Instead of relying on individual fault reports or manual checks, temperatures can be followed continuously and patterns spotted over time.
That makes it possible to discover, for example:
- apartments that often run too warm
- apartments at risk of getting too cold
- imbalance between different parts of the property
- unnecessarily high supply temperature
- incorrect control settings
- deviations that would otherwise be discovered late
When the data is connected to smart control, the heating system can be adjusted more precisely. That can mean optimising the heating curve, controlling on indoor temperature, factoring in weather forecasts or using AI-based analysis to predict how the building will respond.
With Nordic Propeye and our PropSaver service, all property data is gathered in one digital platform, making it easier to follow developments, identify deviations and make decisions based on actual operating data, not guesses.
How much can an association save with energy optimisation?
The size of the saving always depends on the building's conditions. An older building with large temperature differences, poor balancing and a high supply temperature often has different potential than a newer building with already well-functioning operations.
That is why savings should be discussed credibly. Most properties save 10–20 percent of their heating costs with modern energy optimisation. Boverket highlights follow-ups of buildings where settings were corrected and systems optimised, showing energy use reduced by between 5 and 35 percent. It is a wide range, but it shows that operational optimisation can have a large effect when done systematically.
In PropSaver, the heating system is optimised on the building's actual indoor temperature. Data from temperature sensors gives the association a better basis for controlling heat precisely, instead of relying only on outdoor temperature or fixed settings. PropSaver also factors in weather forecasts, adapting the heating control to how the building is expected to respond over time. The saving is always unique to each property and its conditions.
Why energy optimisation becomes a board question
For an association, energy optimisation is not just a technical question. It is an economic and strategic one.
When district heating prices rise, the association's operating budget is hit directly. Unmanaged, those costs risk leading to higher fees, postponed maintenance or less financial room to act.
At the same time, residents expect the board to work actively on both cost control and sustainability. Energy optimisation becomes a way to show responsibility: for the finances, for comfort and for the property's long-term value.
It also gives the board a better basis for decisions. With digital follow-up it becomes easier to track the effect of measures, spot deviations and communicate clearly with members.
Energy optimisation, submetering and smart building control
Energy optimisation works best when seen as part of a larger digital ecosystem for the property. Heat, water and electricity are connected, both technically and economically.
That is why Nordic Propeye also provides IMD Electricity and IMD Water. With IMD Electricity, the association cuts electricity costs through shared electricity and individual metering, while IMD Water makes it possible to bill residents for their actual water use.
Together, energy optimisation, IMD Electricity and IMD Water give better control over the property's operating costs, and better data behind them. Energy optimisation helps the association steer shared heating more efficiently, IMD Electricity removes unnecessary electricity costs tied to separate subscriptions, and IMD Water brings fairer billing and lower water use.
Further reading: see our guides on how shared electricity with submetering works in an association and what IMD Water means for housing associations.
Which rules and requirements should an association know about?
Energy optimisation also grows in importance as requirements on building energy performance evolve.
Boverket states that buildings let with a right of use, such as tenant-owner apartments and rentals, must have a valid energy performance certificate. The certificate is valid for ten years and shows, among other things, the building's energy performance.
At EU level, the revised Energy Performance of Buildings Directive, EPBD, has sharpened the direction for energy efficiency across the building stock.
For an association this means energy optimisation is not only a way to manage today's costs. It is also a way to prepare the property for tomorrow's requirements.
How an association gets started with energy optimisation
A good start is a clear picture of the current state. That is not just about reading energy invoices, but about understanding how the building actually behaves.
The next step is identifying which measures create the most value. In some buildings that means installing temperature sensors and creating a better overview. In others, more advanced control, forecast-based control or AI-based optimisation may be relevant.
The point is that the solution should be adapted to the building. Energy optimisation is at its best when it builds on real operating data and is followed up over time.
What should you look for when choosing a solution?
When an association evaluates an energy-optimisation solution, it pays to ask concrete questions:
- What data is collected from the property?
- Can the system measure actual indoor temperature?
- How often is the data updated?
- Can the system identify deviations?
- Do the board and the property manager get a clear overview?
- Can the solution be combined with the existing heating system?
- Can the saving be followed up over time?
- How secure is the communication between sensors and platform?
With PropSaver, Nordic Propeye helps associations and property owners understand and optimise the property's heating operations. Wireless temperature sensors, digital follow-up and smart control let the heating system be optimised on actual indoor temperature and weather forecasts. That gives you better control over operations, a clearer basis for decisions and better opportunities to cut unnecessary energy use.
Summary: energy optimisation makes the property smarter
Energy optimisation is about using data, sensors and smart control to cut unnecessary energy use without hurting comfort. For housing associations and property owners it is a concrete way to meet rising district heating costs, gain better control of the operating budget and create a more even indoor climate for residents.
When the heating system is controlled more precisely, the building can use less energy where it is not needed, and at the same time deliver better comfort where it actually is.
At Nordic Propeye we help associations and property owners take the step from reactive operations to smart, data-driven building control. With temperature sensors, digital follow-up and energy optimisation it becomes easier to make the right decisions, track the effect and future-proof the property.
Frequently asked questions
What is energy optimisation in a housing association?
Energy optimisation in a housing association means the property's energy systems are measured, controlled and adjusted to cut unnecessary energy use. It often centres on optimising the heating system using indoor sensors, operating data and smart control.
What is the difference between energy optimisation and energy efficiency?
Energy efficiency is a broader concept that can cover both operational measures and larger investments. Energy optimisation focuses more on improving how existing systems are controlled and used day to day.
How much can an association save with energy optimisation?
The saving depends on the building's condition, heating system, control and earlier measures. Most properties save 10–20 percent of the heating cost, and Boverket highlights examples where optimised systems cut energy use by 5–35 percent. For an individual association, the potential always needs to be assessed against the building's actual conditions.
Do we need to replace the heating system to optimise?
Not necessarily. Many measures are about better measurement, balancing, follow-up and control of the existing system. That is why energy optimisation can often be a first step before larger investments become relevant.
Does energy optimisation work in older buildings?
Yes, often very well. Older buildings tend to have larger variations in temperature and operations, so better measurement and control can have a clear effect.
Can energy optimisation improve the indoor climate?
Yes. When the heating system is controlled on actual indoor temperature, it becomes easier to bring down rooms running too warm, spot cold zones and create a more even indoor climate.
Why are temperature sensors important?
Temperature sensors make it possible to understand how the building actually feels indoors. They give the board and the property manager a better overview and make it possible to optimise the heating system on real temperatures, not just outdoor weather.
Does it work with a heat pump?
Yes. The control sits on the heating substation and works whether the building is heated with district heating, a heat pump or a combination.
What happens if the internet goes down?
The heating substation keeps working locally with its latest settings, so the building is never left without heat or control.