Heat pumps – Voltmax Energy Solutions in Luxembourg

Q: Why Choose a Heat Pump?

Unlike conventional heating systems that generate heat, heat pumps transfer heat between the inside and outside of your home. This process makes them significantly more efficient, providing both heating in winter and cooling in summer.

Q: Why a Heat Pump is the Right Choice?

While heat pumps require an initial investment and optimal insulation, the long-term benefits far outweigh these concerns. Modern heat pump technology ensures effective heating even in colder climates, and government incentives in Luxembourg significantly reduce installation costs. Furthermore, with their ability to provide both heating and cooling, along with lower energy consumption and minimal environmental impact, heat pumps are a future-proof solution for homeowners.

Increasing Self-Consumption in a Home in Luxembourg

Piotr Porębski — Fri, 05 Jun 2026 07:43:13 +0000

Self-consumption is the portion of energy produced by a photovoltaic system that is used on site in the home instead of being exported to the grid. The higher the self-consumption, the more electricity is actually used for your own needs: powering household appliances, heating, hot water or charging an electric car before there is any need to buy energy from outside. Why is this so important? Because self-consumption directly affects bills and the sense of control over energy costs. Instead of relying on the rate at which exported energy will be settled, you use it immediately at the moment it is produced. As a result, the PV system is used more effectively and electricity costs become more predictable. Photovoltaics and an energy storage system can help increase self-consumption, while simple solutions can deliver a very strong practical effect.

Why does a home have low self-consumption without an energy storage system?

A home without an energy storage system often struggles with low self-consumption. This is because photovoltaics are most effective around midday, while typical household consumption increases in the morning and evening. During the day, residents are usually away from home, and the main appliances run only briefly or not at all. In the evening, the situation reverses: cooking, laundry, lighting, electronics and heating cause energy demand to rise, while PV production drops to zero.

Low self-consumption is usually not a problem of a poor installation, but rather a mismatch between two profiles: when electricity is produced and when it is needed. As a result, surplus energy appears around midday and is exported to the grid, while later – when the home uses more electricity – energy is drawn from the grid again.

An energy storage system as a tool for increasing self-consumption

An energy storage system solves the most common problem of home photovoltaics: electricity is produced during the day, while the highest consumption often occurs only in the afternoon and evening. A battery makes it possible to store surplus production during sunny hours and use it later, when the PV system is no longer generating. This keeps more energy in the home and increases self-consumption. A storage system does not make the PV installation produce more electricity; it simply helps make better use of what has already been produced, reducing the amount of energy exported to the grid and increasing the share of electricity used on site. The result is usually lower grid consumption in the evening and more predictable bills.

The subject of backup power also often comes up. This is important because self-consumption and backup are two different functions: one is designed to reduce bills, while the other is intended to maintain power supply during an outage. They can work together, but usually require appropriate settings, such as keeping a reserve of energy in the battery for emergencies.

How to size an energy storage system for a home without overpaying?

The best way to start sizing an energy storage system is by looking at two simple things: how much electricity from the PV system is produced as surplus during the day, and how much energy is used after sunset, when the PV system stops generating. It is this evening and night-time consumption that determines whether the battery actually has energy to deliver and how much it will improve self-consumption.

A storage system that is too small usually fills up quickly on sunny days, while further surplus energy is still exported to the grid, so the effect of the battery may be limited. On the other hand, a storage system that is too large can operate inefficiently most of the time, because in a typical home there is not always enough surplus energy to fully charge and then use it. In that situation, you are paying for capacity that is rarely used. That is why the best approach is to match the storage system to the real rhythm of the home: when household members are at home, which appliances run in the evening, whether there is a heat pump, electric vehicle charging, water heating, and what the usage habits are. In practice, the goal is to find a capacity that regularly charges during the day and has a meaningful amount of energy to deliver in the evening, without oversizing the investment.

Photovoltaics + heat pump - how to use electricity from the roof?

A heat pump can significantly increase self-consumption because it is one of the largest energy consumers in the home. The key is to shift part of its operation to the hours when photovoltaics generate the most electricity, instead of leaving everything until the evening. This means more roof-generated electricity is used on site and less energy has to be purchased from the grid later. The simplest and very effective example is heating domestic hot water around midday. The DHW cylinder then acts as a buffer: the heat pump uses PV electricity, and hot water remains available later when production drops. Similarly, in transitional seasons, gentler operation during the day can be scheduled so that the home maintains a comfortable temperature without sudden evening peaks. In practice, this is done through sensible schedules and control priorities – when water should be heated, when the system should work harder and when it should operate more calmly. It is important, however, not to pursue self-consumption at the expense of household comfort. The best result comes from settings that increase the use of PV energy while still maintaining thermal comfort and a stable indoor temperature.

PV + EV - how to charge a car with the help of photovoltaics?

Charging an electric car with the help of photovoltaics makes sense when it happens during production hours, not only in the evening. The best tool for this is a wallbox, which is a home charger for an electric vehicle mounted on a wall or post and permanently connected to the electrical installation. It allows you to set charging schedules and control power in a much more predictable way than a standard socket. In practice, the car charges around midday, when the PV system produces the most energy, instead of drawing electricity from the grid when the sun is no longer generating.

Adjusting charging power to the current surplus from the installation also makes a big difference. Instead of charging at maximum power and drawing the missing energy from the grid, it is better to match the charging speed so that as much electricity as possible comes from the roof. This approach increases self-consumption and usually delivers a better result over the course of a month, even if a single charging session takes a little longer.

Automation and energy metering have the greatest impact here – in other words, information about how much electricity the home is currently using and how much real surplus is available from the PV system. When the system can see this data, it can intelligently manage car charging: speeding it up when there is plenty of sun and slowing it down when the home starts using more energy. As a result, an EV becomes one of the best ways to increase self-consumption, especially in homes where the car is often parked at home during the day.

When does an energy storage system make sense, and when is it better to skip it?

An energy storage system makes sense primarily when surplus energy from photovoltaics appears regularly during the day, while the home still has significant consumption in the evening and at night. In that situation, the battery actually stores energy and later delivers it, so self-consumption increases in a noticeable way. The second case is the need for backup power – then the storage system is chosen not only for lower bills, but also for comfort and safety, provided that the system is properly configured.

There are, however, homes where a storage system is not the first step. If you already use most of the energy during the day, for example because you work from home, have high real-time consumption, charge your car at midday or run the heat pump mainly during electricity production hours, self-consumption can be high even without a battery. In this scenario, proper automation often delivers a greater effect: schedules, wallbox control, heating DHW at midday and settings that shift consumption to sunny hours. If there are large surpluses and evening consumption is also clearly noticeable, a storage system makes sense. If surpluses are small or the home already uses most of the production on site, it is better to start with control settings and adjusted habits, and only consider a storage system as the next step.

How does Voltmax help increase self-consumption at home?

Voltmax helps increase self-consumption at home by matching the entire system to how the household actually uses energy. We select photovoltaics, an energy storage system and a wallbox based on the consumption profile, taking into account heat pump operation and the times when the highest loads occur in the home. As a result, the installation is not oversized and the storage system does not operate without real benefit.

A large part of increasing self-consumption comes down to the right control settings, which is why our goal is to configure energy-use priorities: first the home, then the energy storage system, and then car charging or exporting energy to the grid. We also set a backup reserve if this is important, as well as DHW and EV charging schedules, so that as much energy as possible is used during production hours. The installation conditions of the storage system are equally important: we select the location with temperature, ventilation and service access in mind, as this affects stable system operation.

Finally, we commission and configure the installation so that it works predictably and does not require manual supervision every day. If you are interested, we will prepare a proposal tailored to your energy use and goals, and then choose the settings so that self-consumption increases in practice, not just on paper. Contact us.

The post Increasing Self-Consumption in a Home in Luxembourg appeared first on Voltmax Energy Solutions in Luxembourg.

Can a Heat Pump Work as an Air Conditioner?

Piotr Porębski — Thu, 28 May 2026 07:59:45 +0000

A heat pump has become a popular device that is increasingly found in homes. It performs very well on cold days, when it helps heat the building, but during hot weather the effects of using the unit in the opposite direction can vary. Much depends on how the home distributes cooling. Cooling through a water-based system, such as underfloor heating, ceiling cooling or fan coil units, works differently from air-based cooling, such as a traditional split or multi-split air conditioning system. The latter is also a heat pump, just a different type. The chosen solution affects not only how quickly the temperature drops, but also whether the air is dehumidified, how noticeable the airflow is, and what level of comfort you get in the bedroom or living room. So can a heat pump work as an air conditioner? When is a reversible system a better choice than traditional air conditioning?

What is a reversible system in heat pumps?

A reversible system in a heat pump means that the device can reverse the direction of the refrigeration cycle. Instead of taking heat from outside and transferring it into the home, in cooling mode it removes heat from inside the building and transfers it outdoors. As a result, the same system can provide heating in winter and cooling in summer, provided the home is able to distribute that cooling effectively.

Active vs passive cooling

Heat pump cooling can work in two ways: actively or passively. Active cooling means that the heat pump uses the compressor and reverses the cycle in the same way as an air conditioner — it removes heat from the home and releases it outside. This provides a more noticeable cooling effect, but it also involves higher energy consumption because the compressor is operating during this time. Passive cooling is mainly found in ground source heat pumps. Instead of intensive compressor operation, it uses the naturally lower ground temperature as a cooling source, while electricity is needed mainly to run the circulation pumps and controls. The effect may be gentler than with active cooling, but it is a very economical and stable solution, especially during longer periods of warm weather.

Cooling a home with a heat pump

Cooling a home with a heat pump is most often done through a water-based system, the same one that is used for heating in winter. In practice, cooling can be distributed through underfloor heating, wall or ceiling installations, as well as through fan coil units. Each of these solutions works slightly differently: large surfaces such as the floor or ceiling cool gently and evenly, while fan coil units can react more quickly and provide a more noticeable effect because they operate with forced air circulation. In homes designed with a heat pump and low flow temperatures in mind, underfloor cooling is the most common solution. Ceiling or wall cooling is more often used where the investor plans summer comfort from the very beginning and wants cooling without airflow. Fan coil units, on the other hand, are chosen when stronger cooling is expected or when underfloor cooling does not provide a sufficient effect, especially in rooms with high heat gains, such as attics or rooms with large glazing.

When is a reversible system better than traditional air conditioning?

A reversible heat pump system makes the most sense when the home is already prepared to operate at low temperatures, for example with underfloor heating, ceiling heating/cooling or fan coil units. In this configuration, you can achieve cooling that is quiet and discreet because it does not rely on strong airflow in the room. For many people this is a major advantage, especially in bedrooms or in spaces where they dislike the feeling of moving air. This solution also works well when you prefer a gentle temperature drop and your comfort depends on stable indoor conditions.

If you have a ground source heat pump, passive cooling becomes an additional option. It uses the natural coolness of the ground — energy consumption is very low because the compressor does not need to operate. This is an ideal solution when you want to achieve a longer-lasting cooling effect.

A reversible system also has an advantage where you want to combine cooling with home automation and manage temperature in a more integrated way. You can set zones, schedules and priorities depending on the weather and whether household members are present, and sometimes also link operation with photovoltaics so that cooling runs when energy is cheapest or available from your own production. As a result, cooling becomes part of one coherent home comfort system.

When will traditional air conditioning be better?

Traditional split or multi-split air conditioning will be the better choice when you want fast, clearly noticeable cooling, especially during heatwaves or after returning to a hot home. Its major advantage is also air dehumidification. In summer, this function significantly improves comfort and helps reduce the feeling of stuffiness. This system works particularly well in rooms with high heat gains, such as attics, sunny living rooms or rooms with large glazing. In such spaces, underfloor or ceiling cooling may be too gentle and too slow to respond. If your priority is a strong cooling effect, humidity control and a predictable result, traditional air conditioning will usually be the safer choice.

How to choose a home cooling solution?

When choosing a home cooling solution, it is worth starting with a simple question: what do you expect in summer as a guarantee of comfort? If you value silence, no airflow and a gentle reduction in temperature throughout the home, water-based cooling makes the most sense, whether through underfloor, wall or ceiling systems, or fan coil units. If, however, you want a fast effect during hot weather, clearly cooler air and dehumidification, a more predictable choice will be air-to-air conditioning in the form of a split or multi-split system. And if you have a ground source heat pump, it is worth checking passive cooling, as it can provide stable, gentle cooling with low energy consumption.

To make the comparison easier, here is a short overview of the most popular options:

Solution	Comfort and speed	Dehumidification	Condensation risk	Noise	Installation cost	Typical effect
Underfloor cooling	Gentle, slower	Usually limited	Higher, requires dew point control	Very quiet	Low if the system already exists	Gentle temperature reduction, stable comfort
Fan coil units	Faster than underfloor cooling, more noticeable	Possible, depending on the model and settings	Lower than with underfloor cooling, but condensate requires drainage	The fan is audible	Medium	More noticeable room cooling, better response to heatwaves
Split air conditioning	Fastest effect	Yes, as standard	Low during use	Indoor airflow is audible	Medium to higher	Strong cooling and dehumidification, good temperature control

How does Voltmax help choose cooling with a heat pump or air conditioning?

Voltmax helps select a cooling solution that suits the home and provides real relief in summer. We start by assessing the building and its heat gains, meaning what heats the interiors the most: glazing, sun exposure, the attic, insulation and how the rooms are used. Based on this, we propose the right solution: water-based cooling through an existing installation, fan coil units where more power is needed, or traditional split air conditioning when fast results and dehumidification matter most.

Control is also an important element: we select operating settings, humidity control and protection against condensation so that cooling is safe and predictable. We then handle installation, commissioning and system configuration so that the devices operate stably, without unnecessary fluctuations and without disappointment during the hottest days. We will be happy to prepare a cooling proposal tailored to your home and the way you use it. Contact us!

The post Can a Heat Pump Work as an Air Conditioner? appeared first on Voltmax Energy Solutions in Luxembourg.

Luxembourg Heating Cost Comparison 2026

Piotr Porębski — Sat, 07 Mar 2026 17:46:32 +0000

Heating prices in Luxembourg in 2026 are a topic that raises many questions — especially since the rates for gas, electricity, oil, or pellets alone do not show the full picture. In practice, the actual costs are determined not only by the fuel price, but also by the efficiency of the heating appliance and fixed charges, which can significantly affect the final bill. That is why we compare heating sources using a common denominator: the cost of 1 kWh of useful heat, meaning the heat that actually reaches the home. This approach makes it possible to compare different forms of heating fairly. Based on current reference data for Luxembourg, we show which solutions are the most cost-effective in everyday use. We also explain why the same heating source can be cheaper for some users and more expensive for others — and which factors matter most here. If you are planning to modernize your heating system or simply want to better understand your bills, this comparison will help you make a more informed decision.

Reference fuel prices

Heating costs in Luxembourg can vary significantly not only because each energy source has a different price, but also because different heating systems “produce” different amounts of heat from the same energy. That is why simply comparing the “price of gas” with the “price of electricity” can be misleading.

Below, we compare the most popular heating sources in Luxembourg (gas, electricity, heating oil, pellets). We examine how much 1 kWh of actual heat in the home costs and what the annual bill may amount to for typical demand.

The fairest comparison is the cost of 1 kWh of useful heat (that is, the heat that actually warms the interior). This is important because:

resistive electric heating converts 1 kWh of electricity into about 1 kWh of heat,

a gas/oil boiler has losses and usually delivers less than 100%,

a heat pump can, under favorable conditions, “produce” 3–4 kWh of heat from 1 kWh of electricity (this is the so-called seasonal efficiency/SCOP).

In the calculations, we assume typical seasonal efficiencies:

gas (condensing): about 92%

oil: about 88%

pellets: about 88%

heat pump: SCOP about 3.2 (in reality it is often 3–4, depending on the system and temperature)

Gas (household tariff 01/01/2026 – SUDgaz Classic, prices excluding 8% VAT)

gas: 0.4455 €/m³ + network: 0.2202 €/Nm³, taxes: 0.00108 €/kWh + 0.00912 €/kWh CO₂, fixed charges including 8.69 €/month (network access) + a service fee depending on capacity (e.g. 5 €/month for <10 kW)

calorific value of gas (SUDenergie): 10.2 kWh/m³

Heating oil

official price in Luxembourg (10/02/2026): 0.867 €/l (TVA incl.)

energy in 1 liter (typically): ~10 kWh/l

Wood pellets

example price of bulk pellets with delivery: from 373.22 €/t – it is worth remembering that the price depends on the quantity

example price of bagged pellets in a store (Hornbach LU): 6.79 € / 15 kg

energy in pellets: ~4.8 kWh/kg

Comparison of the cost of 1 kWh of heat depending on the heat source

The cost of 1 kWh of heat from different sources, calculated “after efficiency” of the appliance and based on the reference data above.

Heat pump (SCOP ~3.2): ~0.081 €/kWh of heat
(assuming that 1 kWh of electricity gives about 3.2 kWh of heat; in reality it may be better or worse).

Bulk pellets (about 373 €/t): ~0.088 €/kWh of heat

Condensing gas (with typical fixed charges): ~0.10 €/kWh of heat

Heating oil (0.867 €/l): ~0.099 €/kWh of heat

Bagged pellets (6.79 €/15 kg): ~0.107 €/kWh of heat

Resistive electric heating: ~0.258 €/kWh of heat (because 1 kWh of electricity ≈ 1 kWh of heat)

In practice, this means that under current market conditions in Luxembourg, a heat pump and pellets purchased on favorable terms (in bulk) are most often the most cost-effective options, while resistive electric heating is usually the most expensive option to operate.

Example annual heating cost for a house

If a building uses about 15,000 kWh of heat per year (heating + part of the hot water demand – depending on the standard of the house), the approximate costs may look as follows:

Source	Annually (15,000 kWh of heat)
Heat pump (SCOP 3.2)	~1,209 € / year
Bulk pellets	~1,325 € / year
Heating oil	~1,478 € / year
Condensing gas	~1,506 € / year
Bagged pellets	~1,607 € / year
Resistive electric	~3,870 € / year

What has the biggest impact on the result? 4 factors that change heating costs

First, building insulation and the supply temperature of the system are of huge importance. A heat pump is most cost-effective where the house has reasonable thermal insulation and the heating system operates at low temperatures (e.g. underfloor heating or large radiators). Then the SCOP increases and the cost of 1 kWh of heat decreases.

Second, in the case of gas, fixed and network charges matter. Even if gas itself looks attractive when converted per m³, the bill is increased by the network component, taxes, and fixed monthly items.

Third, not all pellets are equal – what matters is whether you buy them in bulk or in bags, and how much you can order at one time. The difference in price per ton often amounts to hundreds of euros over a season.

Fourth, in the case of electricity, variability results from how charges and support mechanisms are structured. In Luxembourg, there have been significant changes and state interventions concerning elements of the energy bill from 2026 onward.

Which form of heating should you choose in Luxembourg if you are looking for a long-term solution?

If you want the lowest possible heating costs over the long term, then in many cases a heat pump is the winner, because it works like an energy “multiplier”: you pay for 1 kWh of electricity and get several kWh of heat.
Additionally, in practice it is often combined with photovoltaics, so part of the energy for heating (especially during transitional periods) may come from your own roof, which stabilizes costs.

Gas and oil are still sometimes chosen where the priority is the simplicity of replacing a heat source “1 to 1,” and the building has a higher supply temperature while system modernization is limited. Pellets, in turn, are interesting for people who want a “physical” fuel and have space for storage, but it is important to remember about delivery logistics, storage space, and fuel quality.

RTL TODAY also recently discussed the long-term benefits. You can read the findings of the Danish study here.

Energy prices in Luxembourg - key conclusions in 2026

If we compare the actual cost of 1 kWh of heat, rather than fuel prices alone, then in Luxembourg a heat pump and pellets (especially bulk) are usually the best options, while resistive electric heating is usually the most expensive to operate. Gas and oil can be comparable in terms of cost, but the final bill depends on fixed charges, tariffs, and the efficiency of the appliance.

How can Voltmax help with choosing heating and lowering bills?

If you want to compare heating costs in Luxembourg using the example of “your home,” you will reach sensible conclusions the fastest when you calculate the actual energy consumption and check how the system will perform under your conditions. Voltmax can help you with this: we prepare preliminary calculations (heat demand, annual kWh, projected bills), select the right equipment (e.g. heat pump and accessories, system modernization, solutions for low supply temperature), and if you are planning to combine heating with photovoltaics, we match the system so that it actually lowers heating and electricity costs over the year.

In practice, it looks like this: based on data about the building (floor area, insulation standard, type of radiators/underfloor heating, previous bills, comfort preferences), we prepare a comparison of scenarios, e.g. gas vs. heat pump, pellets vs. heat pump, and the “heat pump + photovoltaics” variant. Thanks to this, you compare not only the fuel price, but the actual cost of 1 kWh of heat and the annual heating cost for your case. Additionally, we help you go through the topic of subsidies and formalities – so that the whole thing is calculated not “by eye,” but according to current rules and real figures.

Worried about noise or vibrations from a heat pump? Contact us to design a neighbor-friendly system.

The post Luxembourg Heating Cost Comparison 2026 appeared first on Voltmax Energy Solutions in Luxembourg.

Heat pumps that are neighbor-friendly – noise, vibrations, and placement

Piotr Porębski — Sat, 14 Feb 2026 17:43:49 +0000

A heat pump is a device that generally does not bother anyone—it is not too loud, so it should not cause conflicts. However, in certain situations its placement and installation can be quite troublesome and negatively perceived by residents of nearby homes. It does not matter whether the device is branded and exceptionally high-quality—if it stands in a corner between walls (here the sound strongly reflects and carries) or too close to the property boundary—such a device can be annoying. We are in the same situation if our heat pump operates under the bedroom window—ours or the neighbor’s. You could say the installation behaves like a small “speaker” for the surroundings. Besides the fan noise, the unit may produce other sounds, such as humming or transmitting vibrations into the building structure. The problem can intensify at night—when it is quiet outside, even a moderate sound becomes much more audible, and additionally on frosty days the device’s operation can be more intense.

The good news is that most modern devices are already quite quiet and do not exceed the level of a normal conversation. In most cases, noise issues can be eliminated without “expensive tricks”. You just need to think of the heat pump as a device that must be wisely integrated into the property: choose the right location, ensure vibration damping, and avoid creating conditions in which sound will be amplified.

Which heat pumps are quieter, and which require more attention?

Whether a heat pump is quiet or loud depends primarily on where the sound source is located. The loudest will be devices that perform most of their work outdoors. This way we can hear the compressor and the fan working in the open air. Heat pumps enclosed in technical rooms will behave much more quietly. The devices that require the most attention are those that have an outdoor unit. It is the most audible to the surroundings—this applies to both air-to-water and air-to-air heat pumps. Ground-source heat pumps, on the other hand, do not need an outdoor fan—their operation takes place mainly inside the building. Here, proper soundproofing of the technical room and correct decoupling of vibrations from the floor and walls are important.

A separate category includes systems with several units, also called cascades. Here, there may be a risk of sound adding up from each unit. More often, there is also a situation in which one unit goes to higher speeds while the others operate steadily and calmly. It is important to prepare the design of the system layout and its control well.

In the table below, we present a summary of how the different types of heat pumps differ from each other:

Type of heat pump	What can you usually hear?	Where does the problem appear?	What most often helps?
Air–to–water	fan noise, compressor operation; sometimes a temporary increase during defrosting	corners and recesses by walls, spots under windows, façade mounting that transfers vibrations	a good location (no reflections), stable foundation + vibration isolation, night settings and calmer controller operation
Air–to–air	fan + compressor in the outdoor unit; variable operation depending on load	small plots, close to the boundary, placement in a “corridor” between buildings; audibility at night	sensible location, vibration decoupling, avoiding covers that block airflow, optimally set night mode
Ground-source	mainly sounds from the technical room (compressor, accessories); usually little outside	vibration transfer to slabs/walls, overly “rigid” mounting in the boiler room, too close to bedrooms inside the house	good internal mounting (decoupling), attention to the acoustics of the technical room, proper routing of pipes
Cascade (multiple units)	sound addition from multiple sources; one unit may periodically operate louder	tight development, limited installation space, unfavorable control (frequent “boosting” of speeds)	acoustics-oriented layout design, spacing units out in the area, good control and schedules, possible screening solutions where they make sense

dB level in the catalog vs real noise

In catalogs that contain descriptions of heat pump models, we can often find information about how quiet a given model is. Phrases about a silent mode or the famous wording “super silent” are repeated. However, it is worth remembering that in the catalog we find information about a device that operated under specific conditions. There is no guarantee that on your property it will operate just as quietly. This causes many disappointments, because two heat pumps with similar data in the documentation can in practice operate completely differently. This depends primarily on the location and surroundings, but also on the installation method.

A parameter in the catalog is not the same as the real noise at the place where we are. The perception of loudness is influenced by many factors, such as the distance from the noise source, the direction of the fan discharge, and the surroundings. Sound most often reflects when the outdoor unit stands close to a wall, is located in a corner, or in a narrow passage between two buildings-such conditions work like a megaphone, amplifying the noises produced by the device. It is worth remembering that it is not the pump that works louder-rather, the conditions cause the sound to carry farther or be concentrated in one direction.

The time of day also has a huge impact on how we perceive the sounds produced by a given heat pump model. During the day, background noise—cars driving, people talking, or other city sounds—masks the noise coming from the device. At night, most of these sounds disappear, so the body perceives the heat pump’s operating sound much more clearly. Additionally, during colder nights the device may operate more intensively. All of this means that what during the day seems practically inaudible may bother us at night.

Where does the noise in a heat pump really come from?

A heat pump is a source of various sounds that can appear during different stages of the device’s operation. One day we will not hear it even for a moment, and another day the humming during its operation will catch our attention. In heat pumps, most often three noise sources are involved.

The first is the fan in the outdoor unit—in the case of air-source heat pumps. It produces a steady sound of air noise that resembles a stronger air blow. The fan itself is quite quiet, but the placement of the device plays a big role here. If the pump stands too close to a wall, in a corner, or in a place with restricted airflow—we may encounter audible noise that over time turns into whistling or vibrating. This is caused by the fact that the air reflects and swirls.

The second source of noise is the compressor, which is the heart of the device. The sound coming from it is low, resembles humming, and is particularly audible during changes in speed. The loudness of the compressor’s operation is usually not a problem. The problem arises when vibrations transfer to the structure, which causes the sound to spread through the building. Sometimes this noise can also appear inside the building. The house begins to act like a resonant box and the device’s loudness becomes problematic.

The third source of noise can be moments when the heat pump does not operate evenly. A good example here is the operating cycle called defrost, i.e., defrosting. It activates in cool and humid weather, which causes the device to temporarily change the way it operates. It can increase the speed of both the fan and the compressor. Additionally, there may be sounds related to condensation, dripping, or cracking. It does not last long, but if it occurs at night, it can be noticed.

The moment when it becomes louder than usual

Most often the device starts to operate louder in the case of frost and defrosting-then the heat pump briefly changes its operating mode, can increase speeds, and the sound becomes more audible. This happens especially at night. The second moment is operation at high power-after a break in heating, the house must warm up quickly to reach a specific temperature. Unfavorable controller settings can also unnecessarily increase noise emissions.

Where should you install a heat pump?

The installation location, or the device itself, is not the problem when it comes to emitting noise. Avoid placing the pump in recesses, between walls, or in corners. These are places that act like a resonant box. The noise is amplified, and the fan noise carries more easily in one direction. If the sound additionally encounters an obstacle such as a wall or a fence, it can reflect and come back, which seemingly increases the noise—we feel that the sound is louder even though the device is operating the same.

It is also worth thinking through the location in relation to windows, especially in the bedroom. The sound produced by the heat pump disappears during the day, but at night it can be distinct. It is therefore good to plan placing the heat pump at an appropriate distance from the house and not necessarily on the side where the windows to our rest room are located. Let us also remember the well-being of our neighbors—try not to place the device in such a way that the noise coming from it disrupts their peace.

Here are a few points worth remembering when choosing the installation location for a heat pump:

avoid recesses and corners, because they amplify sound;

position the device so that there is no hard wall opposite it that will reflect the noise;

pay attention to the direction of the air discharge—it must not be directed toward your windows or the neighbor’s;

plan a stable base that limits vibrations;

ensure condensate drainage so that in winter ice does not form under the unit.

Two places where the pump will almost always be louder

There are two heat pump placements that practically guarantee that noise will start to bother us when using the device.

The first is placing the unit under a bedroom window. The sound has a very short distance to travel, and at night the pump’s noises become very burdensome. The second place is a corner or the space between walls, the so-called recesses and corridors between buildings. In this case, the noise does not spread naturally—it reflects off hard surfaces and is amplified. Additionally, restricted airflow can cause the device to run at higher speeds, which also increases audibility.

Vibrations and mounting vs sound transmission

In heat pump noise, what is often the most irritating is not the sounds that are heard outside the building, but those that appear inside the house. We are talking about micro-vibrations generated by the outdoor unit—specifically by the compressor and rotating components. If the installation is done “rigidly”, the building transmits the vibrations further. They turn into a hum that can be felt in rooms inside the house.

The first mistake that should be ruled out is improper seating/foundation. The pump stands on an unstable base, on a light structure, a thin slab, or paving that “moves”, or—worse—on façade brackets without proper vibration decoupling. The result can be that instead of a gentle whoosh you get amplified vibrations at specific frequencies, causing a troublesome, tiring hum transmitted to walls and slabs. To silence this sound, changing the device settings is often not enough—the base and mountings need to be corrected.

The second mistake is poorly selected vibration isolators—either there are none at all, or they are chosen randomly, for example they are too hard or too soft, or simply set incorrectly. In this way, the isolators act like a spring, and the device starts to operate like a swing. This can contribute to one of two scenarios: vibrations can go into the building, causing them to be heard inside, or the unit falls into vibrations that outside sound like buzzing.

The third mistake is vibration bridges in the installation, for example pipes, brackets, or penetrations made rigidly. Even if the heat pump is positioned correctly, vibrations can travel through pipes and mountings into the building structure, resulting in humming—whether in the bedroom or in the living room.

Heat pumps in Luxembourg - what are the requirements?

In Luxembourg there is no golden rule for the entire country that defines one location for the outdoor unit and how far from the fence it should be. The overriding requirements are those defined by a given municipality, i.e., local building regulations (RBVS) and their interpretation. It is at the municipal level that provisions most often appear regarding technical devices outdoors and permissible noise levels. In many municipalities, what matters is what can be heard at the property boundary, not what is presented in the catalog. Therefore, before installation it is worth checking the requirements where you live.

In case of questions from a neighbor or the authorities, it is worth preparing a simple set of documents that will answer most questions. First—noise parameters according to the manufacturer. Second—a plan of the unit’s placement on the plot with marked distances from the boundary and windows. Third—a short description of what has been done to reduce noise. Such measures include proper seating/foundation and all anti-vibration solutions.

Don’t worry about noise, use Voltmax services

Noise when using a heat pump is not the norm. It is usually the result of incorrect placement or vibration transmission. However, a properly selected device and an appropriate location on the property can make the heat pump work excellently-heating the house and not drawing attention to itself.

At Voltmax, we advise on choosing a solution for a specific building. We plan the installation location so as not to direct sound toward windows and neighbors’ houses. During installation we pay attention to the smallest details, such as stable seating/foundation, vibration damping, and correct routing of the system. These are details that later guarantee satisfaction. We also help prepare documentation in a basic version, which in Luxembourg makes the heat pump installation process easier.

If you decide to install a heat pump in your home-contact Voltmax. Describe your house and plot to us, and we will suggest which solution will be acoustically safest and how to plan the installation so that everything goes smoothly and without stress.

Worried about noise or vibrations from a heat pump? Contact us to design a neighbor-friendly system.

The post Heat pumps that are neighbor-friendly – noise, vibrations, and placement appeared first on Voltmax Energy Solutions in Luxembourg.

Thermal Modernisation in Luxembourg: A Smart Way to Cut Bills

Voltmax — Wed, 02 Jul 2025 12:18:39 +0000

Introduction

In a time of rising energy costs and growing environmental awareness, improving your home’s energy efficiency matters more than ever. For homeowners in Luxembourg, thermal modernisation is a practical way to cut energy use, lower bills, and stay comfortable all year.

To begin with, you can start by insulating walls and roofs, upgrading heating systems, or installing solar panels. The good news? Luxembourg doesn’t just support these efforts—it helps fund them.

Moreover, with generous grants at both the national and local levels, energy renovation has never been more accessible. Whether you own a house, duplex, or apartment, it’s not just a green choice—it’s a smart financial move.

In this case, thermal modernisation delivers both environmental and economic benefits. What’s more, it increases the long-term value of your home.

In this guide, we’ll show you what thermal modernisation involves, why it matters, and how to get started. Let’s explore how to make your home warmer, greener, and more cost-efficient—step by step.

Renovating your home in Luxembourg: where energy savings begin

Every energy-saving journey starts with the home itself. In Luxembourg, energy-focused renovation isn’t just about aesthetics or property value—it’s about making your space more affordable, comfortable, and efficient.

High heating bills or outdated systems are common problems, but a smart renovation can fix them and bring long-term benefits. The government of Luxembourg actively promotes thermal renovation as part of its national climate and energy strategy.

Projects like insulation, window replacement, and heating upgrades can reduce energy use and turn your house into a low-consumption home. Moreover, renovation doesn’t have to happen all at once. Many homeowners start with small steps and upgrade gradually.

As a result, generous grants, expert advice, and a growing number of skilled contractors have made starting your renovation easier than ever.

Stopping heat loss: the real problem in older buildings

Older buildings in Luxembourg often come with character — nevertheless, they also hide energy leaks. Many homes built before modern insulation standards lose heat through walls, roofs, windows, and even floors.

In some cases, more than half of the heating energy escapes through the building envelope. This doesn’t just make homes colder in winter and hotter in summer — it also drives up energy bills.

Heat loss also increases your home’s environmental footprint. What’s more, many homeowners don’t realise how much energy they’re losing until they look closely at their usage.

Thermal imaging and energy audits are great tools to find the weak spots. Once identified, you can take focused action — starting with insulation and sealing.

Fixing heat loss in older buildings isn’t just about comfort. On the contrary, it’s the foundation of any successful energy renovation. Without it, even the best heating system or solar panels won’t work as intended.

Insulating walls, roofs and floors to keep the heat inside

Proper insulation is one of the most effective ways to stop heat loss and reduce energy use. In particular, this is true in Luxembourg’s varied climate.

Without good insulation, even the most advanced heating system will struggle to keep your home warm in winter or cool in summer. Walls, roofs, and floors are the most common areas where heat escapes. As a result, upgrading their insulation can lead to noticeable energy savings.

External wall insulation can cut heat loss by up to 25%. Roof insulation alone can prevent up to 30% of thermal energy from escaping.

Floor insulation — especially above garages or unheated cellars — adds extra protection and comfort. Altogether, these improvements deliver the best results. Fortunately, Luxembourg offers strong financial support for such projects. National and local subsidies cover a large part of the cost.

What’s more, with efficient materials and clear energy standards, professional insulation is now a reliable way to save energy and reduce your bills.

Replacing windows and heating systems for better efficiency

Old windows and inefficient heating systems are major obstacles to a truly energy-efficient home. In many Luxembourgish buildings — especially older ones — single-glazed or poorly sealed windows let valuable heat escape.

Outdated boilers and electric radiators also waste energy without providing consistent comfort. Replacing windows with double or triple-glazed models and insulated frames helps keep the heat in and the cold out.

These thermal modernisation upgrades also improve soundproofing and indoor comfort year-round. Moreover, switching to high-efficiency systems, like air-to-water or geothermal heat pumps, can cut energy use by up to 50%.

The cost may seem high at first. However, Luxembourg’s financial support schemes make these upgrades more affordable. In fact, when done together, window and heating system upgrades can unlock extra bonuses through national renovation programs.

Most importantly, they help your home stay efficient and reduce its environmental impact.

Adding solar panels to boost efficiency and cut electricity costs

Once your home is well insulated and your heating system is upgraded, the next step is often solar power. To put it another way, installing photovoltaic (PV) panels lets you generate clean electricity and lower your energy bills.

Solar energy is especially attractive in Luxembourg, where the government offers generous incentives. Modern solar panels are efficient, long-lasting, and adaptable to most roof types and building sizes.

As a matter of fact, by producing electricity at home, you not only save money — you also protect yourself from future energy price hikes. Pairing PV systems with heat pumps or EV chargers can further reduce your carbon footprint.

All in all, this combination offers a powerful step toward energy independence. Eventually, in many cases, homeowners recover their investment within 8 to 12 years.

You might also like: Heat pumps that are neighbor-friendly – noise, vibrations, and placement

Available grants in Luxembourg for energy renovation projects

Homeowners in Luxembourg benefit from a wide range of financial incentives that make energy renovation more affordable. The main support scheme, Klimabonus, covers up to 62.5% of eligible costs for thermal modernisation works like insulation, heat pumps, window replacement, or solar panels. This applies when the energy class improves by at least two levels.

In addition, other programs include Enoprimes (from energy suppliers), low-interest climate loans, and a reduced 3% VAT for older homes. In some municipalities, you can also get local top-up grants covering 10–20% of your renovation costs.

A state-funded energy audit is partly reimbursed, making expert advice easier to access. As a result, these supports can reduce the total cost of deep renovation by up to 60–70%, especially when upgrades are combined.

Your step-by-step plan for a thermal modernisation and more efficient home

Starting an energy renovation project can feel overwhelming. However, in Luxembourg, there’s a clear path to follow.

The first step is to schedule an energy audit with a certified expert, often subsidised by the state. This evaluation will show where your home is losing energy and what to fix first.

After that, create a renovation plan based on the audit. Many homeowners begin with insulation—walls, roof, and floors—then move on to windows and heating systems. Once energy loss is reduced, you can add solar panels to generate clean electricity and save even more.

With this in mind, at Voltmax, we support you every step of the way. From the energy assessment to planning, installation, and grant applications—we handle it all. With the right partner, going green has never been easier or more rewarding.

Conclusions

Thermal modernisation is more than just a home improvement trend in Luxembourg. It’s a long-term investment in comfort, savings, and climate responsibility.

Every upgrade—from insulation and heating to solar power—brings you closer to an efficient, sustainable home. Luxembourg has one of the best grant systems in Europe, making it easier than ever to take action. And you don’t have to do it alone.

At Voltmax, we guide you through the entire process. We help you make the right decisions, secure available subsidies, and complete your renovation with confidence.

A warmer, greener, and more cost-efficient home is not only possible—it’s within reach.

Lower your energy bills with smart thermal modernisation. Fill in the form and get a free audit with expert advice on subsidies in Luxembourg

The post Thermal Modernisation in Luxembourg: A Smart Way to Cut Bills appeared first on Voltmax Energy Solutions in Luxembourg.

Heat Pump Installation in Luxembourg: Costs, Benefits, and Government Incentives

Voltmax — Fri, 14 Feb 2025 10:24:22 +0000

Why Choose a Heat Pump?

As homeowners search for more energy-efficient and environmentally friendly heating solutions, heat pumps are becoming increasingly popular. Unlike conventional heating systems that generate heat, heat pumps transfer heat between the inside and outside of your home. This process makes them significantly more efficient, providing both heating in winter and cooling in summer.

With rising energy costs and growing environmental concerns, heat pumps offer a viable alternative to traditional heating systems. This guide will help you understand their benefits, types, costs, and key considerations, allowing you to make an informed decision for your home.

Advantages of Heat Pumps

1. Energy Efficiency and Cost Savings

Heat pumps move heat rather than generate it, requiring much less energy than traditional heating systems such as furnaces and boilers. This results in reduced energy consumption and lower utility bills. Although the initial installation cost is higher, the long-term savings on energy expenses often make up for the investment.

2. Environmentally Friendly Solution

By utilizing natural heat sources from the air, water, or ground, heat pumps significantly reduce reliance on fossil fuels and lower carbon emissions. This makes them a sustainable choice aligned with global climate initiatives.

3. Year-Round Comfort

Unlike conventional heating systems, heat pumps provide both heating in winter and cooling in summer. This dual functionality eliminates the need for separate air conditioning systems, reducing overall energy consumption.

4. Improved Indoor Air Quality

Since heat pumps do not rely on combustion, they do not produce harmful byproducts such as carbon monoxide. Additionally, they help regulate humidity levels and filter indoor air, creating a healthier living environment.

5. Low Maintenance and Longevity

Compared to traditional heating systems, heat pumps require less maintenance and have a longer lifespan. With proper care, they can operate efficiently for 15 to 20 years, providing reliable heating and cooling with minimal upkeep.

6. Government Incentives in Luxembourg

Luxembourg offers government programs supporting heat pump installations to promote energy efficiency and reduce CO₂ emissions. One key initiative is PRIMe House, which provides subsidies for ecological heating technologies.

For details on available subsidies, conditions, and application procedures, visit the official website of the Luxembourg Environmental Administration. These programs make investing in a heat pump more financially attractive while contributing to environmental protection and reducing energy costs.

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Types of Heat Pumps

Choosing the right heat pump depends on your home’s needs and environmental conditions. Here are the main types:

1. Air-to-Air Heat Pumps

- Extract heat from outdoor air and transfer it inside.
- Provide heating in winter and cooling in summer.
- Ideal for moderate climates and easy to install.

2. Air-to-Water Heat Pumps

- Capture heat from the air to heat water, which then circulates through radiators or underfloor heating.
- Suitable for homes with existing water-based heating systems.

3. Water-to-Water Heat Pumps

- Utilize groundwater as a heat source, offering high efficiency.
- Require a stable water source and professional installation.

4. Geothermal Heat Pumps

- Harness underground heat, maintaining consistent performance regardless of air temperature.
- Higher installation cost but long-term savings due to efficiency.

Installation Costs and Savings

1. Upfront Costs

The cost of installing a heat pump varies based on type, home size, and system complexity. Homeowners can expect costs ranging from €25,000 to €50,000, covering equipment, components, and labor. Geothermal systems tend to be more expensive due to excavation requirements. Additional expenses may include system integration with existing heating infrastructure and potential electrical system modifications.

2. Government Incentives in Luxembourg

To encourage homeowners to invest in energy-efficient heating systems, the Luxembourg government offers financial support through the PRIMe House program. The available subsidies depend on factors such as the type of heat pump, the home’s energy efficiency, and whether the installation is part of a renovation or new construction.

Available Subsidies:

New Constructions: Grants are available based on the energy classification of the building.
Renovations: Up to €8,000 is available for air-to-water and geothermal heat pumps, depending on system efficiency and home insulation.
Energy Bonus for Low-Income Households: Additional support is available for financially constrained households.
Zero-Interest Eco Loans: Homeowners can apply for interest-free loans to cover upfront installation costs.

To apply, homeowners must:

Submit a request to the Administration de l’Environnement before starting installation.
Ensure the system meets approved efficiency standards.
Provide proof of installation by a certified contractor.

3. Long-Term Savings

Despite the initial investment, heat pumps significantly reduce energy bills. Their high efficiency leads to lower monthly heating costs compared to traditional heating systems. Over time, homeowners recoup their investment through reduced energy consumption. Additionally, their long lifespan and minimal maintenance further contribute to long-term savings.

Recommended reading: How a Photovoltaic Installation Works

When a Heat Pump Installation May Not Be Suitable

Heat pumps are a modern and ecological heating solution, but there are situations where they may not be the best option:

1. Poor Building Insulation

If a home has significant heat losses due to inadequate insulation, a heat pump may not operate efficiently. In such cases, improving insulation should be a priority before installation.

2. Extreme Climatic Conditions

In areas where temperatures drop below -25°C for extended periods, air-source heat pumps may struggle to provide sufficient heating. Additional heat sources may be required.

3. Space Constraints

Ground-source heat pumps require sufficient space for horizontal or vertical collectors.
Air-source heat pumps need proper airflow, requiring adequate clearance from walls and obstacles.

4. Utility Room Limitations

The internal unit of a heat pump requires a dedicated utility or technical room with sufficient space for additional components such as a domestic hot water tank or heat buffer. Depending on the model, the unit can take up approximately 0.4 m² of floor space, and certain models require a minimum room volume of 4.1 m³ to 8.2 m³ to accommodate the refrigerant safely.

Furthermore, proper ventilation and accessibility for maintenance must be considered when choosing a location for the installation. If space is limited, alternative solutions, such as compact models or external installation, may be necessary. Ensuring adequate room for all necessary components will contribute to the heat pump’s efficiency and longevity.

5. Short-Term Property Use

If the building is only used temporarily (e.g., short-term rental or pending sale), the investment may not pay off within the expected timeframe.

Before installation, it is advisable to consult a professional for a technical and economic assessment tailored to your specific needs.

Addressing Concerns: Why a Heat Pump is the Right Choice

While heat pumps require an initial investment and optimal insulation, the long-term benefits far outweigh these concerns. Modern heat pump technology ensures effective heating even in colder climates, and government incentives in Luxembourg significantly reduce installation costs. Furthermore, with their ability to provide both heating and cooling, along with lower energy consumption and minimal environmental impact, heat pumps are a future-proof solution for homeowners.

Why Choose Voltmax Sarl for Your Heat Pump Installation?

At Voltmax Sarl, we specialize in heat pump installation, ensuring maximum efficiency and compliance with Luxembourg’s energy regulations. Our services include:

Expert Consultation: A thorough home assessment to recommend the best heat pump solution.
Professional Installation: We follow industry standards and best practices to optimize performance.
Energy Efficiency Optimization: Proper placement and fine-tuning for peak efficiency and savings.
Certified Technicians: Our team undergoes continuous training to stay updated with the latest technology.
Warranty & Support: We provide post-installation support, maintenance, and guarantees.

Contact Voltmax Sarl Today

Phone: +352 661 444 831
Email: info@voltmax.lu
Get a Free Consultation: Fill out the form on our website to explore your options!

Make the Switch to a Heat Pump Today!

Investing in a heat pump is a smart choice for home comfort and environmental responsibility. Voltmax Sarl is here to help you transition smoothly. Contact us today!

Curious how much you could save with a heat pump in Luxembourg? Reach out today and let’s explore the costs, benefits, and incentives tailored to your home

The post Heat Pump Installation in Luxembourg: Costs, Benefits, and Government Incentives appeared first on Voltmax Energy Solutions in Luxembourg.