Brever, a regional player for almost 30 years, is a reliable partner in the manufacture and installation of windows, doors and gates. With a focus on quality, flexibility and customer satisfaction, the company employs 48 people and offers tailor-made solutions encompassing design, assembly and after-sales service.
Idea
A sustainable building for energy efficiency and respect for the environment
The company wanted to build an innovative and sustainable infrastructure, reducing its environmental impact while optimising its operations. The main objective was to create a space combining offices, a showroom and warehouses, while incorporating ecological solutions and regional materials, and working to make the building energy efficient.
Design
Local materials and innovative technologies
The initiative focused on the construction of a sustainable building, incorporating the following criteria:
Local materials: use of wood, exposed concrete and black steel from regional suppliers.
Efficient energy systems: underfloor heating, high-quality insulation, a high-efficiency heat pump and passive cooling.
Innovative equipment: solar protection glazing, customised ventilation with electronic humidity control, and night-time cooling system.
Results
Saving energy and strengthening the regional economy
The new building, opened in December 2023, offers:
Reduced emissions: lower energy consumption thanks to efficient heating/cooling systems and high-performance insulation
Greater regional impact: local sourcing to support the regional economy
Increased comfort: improved indoor air quality and temperature for employees and customers.
Efficient heating system – Heat pumpBuilding air management system
Keller Minimal Windows is a global player renowned for its innovative, high-quality aluminium window and door systems.
At the heart of Keller’s philosophy is a commitment to sustainable business processes and approaches. The company is constantly pushing architectural boundaries while minimising its environmental impact. Its aluminium systems are designed to deliver reliable, long-lasting performance.
Since 2020, Keller has been part of the AluK group, a world leader in aluminium systems, combining family expertise with financial strength. Despite its international presence, Keller retains a personalised and flexible approach, with made-to-measure production based in Luxembourg.
Idea
Reducing carbon footprint while ensuring a sustainable product
Keller is committed to reducing its carbon footprint while maintaining the excellence of its top-of-the-range windows. This ambition is based on several principles:
Eco-responsible materials: giving preference to materials from suppliers who comply with environmental standards
Optimising production processes: reducing waste and energy consumption
Sustainable logistics: minimising environmental impact through reusable packaging and more environmentally-friendly means of transport
Design
Carrying out a carbon audit of the entire value chain
Carrying out a full carbon audit enables us to identify the precise sources of emissions at each stage of the process, from product design to delivery. This carbon footprint is more than just a diagnosis. It provides a strategic basis for implementing concrete, measurable solutions.
Implementation
The stages of the carbon footprint
The implementation of the carbon footprint assessment was structured in several phases:
Analysis of activities: identification of the sources of direct emissions (production, energy consumption, etc.) and indirect emissions (suppliers, transport, end-of-life products, etc.)
Data collection: precise compilation of the information needed to assess the overall impact
Report and recommendations: a detailed report was drawn up, highlighting the main areas for reduction and proposing concrete measures to minimise the carbon footprint.
Results
The results of the carbon footprint on the company’s sustainable development
This assessment has made it possible to implement concrete solutions, such as:
The use of materials with a low carbon footprint
Increased energy efficiency in production facilities
Optimised logistics to limit transport-related emissions.
This analysis and the resulting actions illustrate Keller’s commitment to responsible production and actively contributes to the ecological transition, while guaranteeing top-of-the-range products.
The Hotel Belle Vue in Vianden offers eco-friendly accommodation in the heart of the Luxembourg Ardennes. With 60 comfortable rooms, a wellness area including an indoor swimming pool and sauna, and a restaurant celebrating regional cuisine, it is a destination of choice. Sustainability and energy savings are at the heart of the hotel’s vision, with environmentally-friendly solutions used to reduce the hotel’s carbon footprint.
Idea
Working with all teams on the transition to sustainability
For several years now, the hotel has been actively involved in the transition to energy independence from fossil fuels. This commitment reflects the managers’ vision: to create a welcoming and environmentally-friendly environment, while providing guests with an experience that is both relaxing and sustainable.
Design
Combining heating systems: an integrated, sustainable solution
The heating system at the Belle Vue hotel is based on a multi-component design, designed to maximise energy efficiency while reducing the carbon footprint. Its core element is a 60 kW solar thermal system, complemented by a wood chip boiler, fuelled by local resources to promote short circuits and sustainable management of regional materials.
The solar thermal system captures the sun’s energy to provide heat for all the systems. Large-capacity thermal storage tanks store the heat produced and ensure its continuous availability. Finally, the system incorporates a heat recovery process, using waste heat from the refrigeration compressors to improve overall efficiency and reduce energy losses.
Implementation
A lasting impact beyond the hotel
To meet the specific needs of the hotel, this integrated system has been carefully deployed to ensure optimum performance in all seasons. The wood chip boiler takes care of most of the needs in winter, while the solar thermal system plays a crucial role on sunny days. The thermal storage tanks ensure continuity of service, even in the event of fluctuations in production. Furthermore, the local heating network established means that several neighbouring buildings can also benefit from this sustainable energy. This implementation demonstrates not only the hotel’s desire to reduce its operating costs, but also its commitment to responsible sharing of energy resources.
Result
Predictability of thermal cover
The hotel benefits from a stable and predictable energy supply thanks to a combination of solar energy, heat recovery and wood from local sources. This approach guarantees sustainable thermal cover and reduces dependence on external suppliers and fluctuations in energy prices, offering a high degree of autonomy. This innovative energy system prepares the hotel to meet future challenges, while strengthening its economic position. It also makes a significant contribution to protecting the environment and reducing the hotel’s carbon footprint.
The project involves fitting professional kitchen extractor hoods with heat recovery systems on the exhaust air fan. This recovery can be performed in three different ways:
via an air-to-air recuperator integrated into the hood which propels the preheated air into the kitchen (integrated compensation).
via a separate air-to-air recuperator which also allows the make-up air to be preheated through a plate heat exchanger.
via an air/water heat recovery unit to pre-heat domestic hot water
The company will be able to save an estimated 70-100% on heating consumption in the kitchen, and around 50% on domestic hot water production, by installing this technology, which has been on the market for over 5 years. However, implementing this measure can be complex with a medium-to-long-term return on investment, and requires the temporary shutdown of production during the technical installation stage.
Replacement and centralisation of cold production units with a variable speed compressor
The project consists in fitting cold rooms and/or freezers in the butcher shop with cold air curtains to prevent warm air flows from entering cold rooms and freezers when their doors are opened.
By installing this technology, which has been available on the market for over 5 years, the company can save on its electricity bills by an estimated 10%. This measure is rather easy to implement and would entail a medium-to-long-term return on investment. Implementing this measure does not require production shutdown during the technical installation stage.
Replacement and centralisation of cold production units with a variable speed compressor
A refrigeration cycle works by drawing heat from the evaporator and discharging it to the outside (condenser). The project’s idea consists in recovering this heat to be discharged to preheat domestic hot water (DHW), which is necessary in every restaurant. The exchanger is placed between the compressor and the condenser of the cooling unit.
In practice, recovery can be implemented in three different ways:
Via external exchanger: an exchanger is connected on one side to the compressor outlet and on the other to the hot water tank (partial recovery).
Via internal exchanger: a “desuperheater” through which the refrigerant flows are inserted at the bottom of the hot water tank upstream of the condenser.
Via condensation water collector: all the refrigerant is condensed inside the hot water tank (total recovery).
By installing this technology, which has been available on the market for more than 5 years, the company can save significantly on its energy bills, and even cut its hot water consumption, which will result in reducing its carbon footprint (the benefits will depend on the initial mode of domestic hot water production). However, implementing this measure can be complex and taking into account energy costs alone may not be sufficient for a return on investment. It also requires temporary production shutdown during the technical installation stage.
Replacement and centralisation of cold production units with a variable speed compressor
In a restaurant, the cold room’s refrigeration cycle is often subject to variations in operation.
The air evaporator is influenced by the climate of the room it cools (opening and closing of doors, loading of food, etc.) while the condenser also depends on the climate through the outside temperature.
The project consists in replacing small production units supplying cold rooms with a main, centralised cold production unit, controlled with a frequency variation on the refrigeration compressor motor.
By installing this technology, which has been available on the market for more than 5 years, the company can save up to 15% on its electricity bills and reduce its carbon footprint. However, implementing this measure can be complex and requires the temporary shutdown of production during the technical installation stage. But the return on investment will be fast thanks to the savings achieved.
Smart climate control is performed on a large set of building data over long periods to identify malfunctions and savings opportunities, while enabling the user to assess the effectiveness of corrective measures that are taken.
This technology is suitable for hotels with manually controlled technical equipment such as heating, ventilation, and air conditioning.
Setting up this new technology will allow the company to save energy, while slightly reducing its carbon footprint. This measure is simple to implement with a medium-to-long-term return on investment and it does not require shutdown of production during the technical installation stage.
Building management system (BMS) is an interface which remotely controls electronic and mechanical systems in one or more buildings. In particular, BMS takes care of the remote control of the hotel’s heating, ventilation and air conditioning systems, which consume a lot of power.
This technology is suitable for existing hotels wishing to retrofit a BMS system, as well as new buildings where BMS is implemented from the design stage.
The company will be able to make substantial energy savings and reduce its carbon footprint by installing this technology, which has been on the market for over 5 years. This measure is quite simple to implement, even if there is a medium-to-long-term return on investment and it requires a partial shutdown of production during the technical installation stage.
Decentralisation of domestic hot water production with or without thermodynamic water cylinder
The project consists in separating the hot water production system from the heating system. This can be done in two ways:
through partial decentralisation in summer, by adding a small boiler to heat the domestic hot water. It will allow to shut down the main boiler in summer but will still be connected to the hot water system. Decentralisation can also not be total if the domestic hot water production system is separate, either following the installation of a thermodynamic water cylinder operating at high temperature (advantage of the COP on electricity consumption linked to the production of DHW compared to an electric boiler)
through the installation of a boiler sized to cover the DHW requirement, or the installation of suitable electric boilers with storage capacity to limit power demand peaks.
This technology is particularly suitable for hotels with a high demand for domestic hot water. Setting up this new technology will allow the company to save energy, while reducing its carbon footprint. However, implementing this measure can be rather complex with a medium-to-long-term return on investment, and requires the temporary shutdown of production during the technical installation stage.
