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De Altis: a circular and energy-neutral sports complex
De Altis: a circular and energyneutral sports complex
De Altis. The new, multifunctional sports complex in Rijswijk named after the place in ancient Greece where the prizes for the best athletes of old Olympus were made. In Rijswijk, it is ‘the’ place where residents can play sports and exercise both indoors and outdoors, and meet each other. The sports complex is constructed to be fully circular, whereby recycled materials have been utilised. The complex is also fully energy neutral. 100% renewable energy is used, and 0% fossil fuels. But what does this involve, technically?
Responsible for design, procurement, and delivery Iv-Bouw as EPC partner was involved from start to finish in the realisation of this sports complex. Jaco Mooijaart, Head of Department of Electrical Engineering and Mechanical Engineering, explains: “The municipality of Rijswijk issued a request that roughly stated: we have a budget of 13.5 million euros, and for this, we would like at least two connected sports halls with a clear height of seven and nine metres, a weights room, dance/budo hall and two catering establishments. Together with project developer OLCO and AGS Architects, Iv-Bouw presented a plan for an energy-neutral building. We won the tender because of the appearance, the proposed parking solution, and the expected energy consumption of our plan. Iv-Bouw as EPC partner assumed the risk-bearing responsibility for designing all electrical and building installations, purchasing the systems, and the installation and delivery thereof. Iv-Bouw devised all technical installation designs and purchased the installations from various parties. As EPC partner, we were also ultimately responsible for the implementation.”
Using the space smartly De Altis is a multifunctional sports complex with an appearance unique to Rijswijk. The complex has a total floor area of 6,150 m2. It consists of two large sports halls that can be used for volleyball, basketball, badminton, and physical education, among other sports and activities. In addition, there is a weights room for strength training, a large budo hall, and two sizeable catering facilities linked to the stands. A parking garage with an area of 2,400 m2 has been realised beneath part of the complex. A smart solution whereby extra space has been created at the front of the terrain for outdoor sports such as running and boot camp activities and room for future residential construction.
Applications for a self-sufficient building The roof of De Altis contains no fewer than 1,100 solar panels, covering almost the entire (high) roof. In addition, the shaded roof areas were given a green roof – with moss and sedum plants. An advantage of this is that green roofs provide a buffering function and cool the building with the rainwater retained by the moss and plants. The application of many solar panels is just one of the sustainable measures used in this new sports complex.
An ATES installation contributes to optimal self-sufficient energy generation.
A Heat and Cold Storage (ATES - Aquifer Thermal Energy Storage) installation was applied for the heating and cooling of the building. Heat is also recovered in the building from the return ventilation air. Therefore, the cooling of the rooms and the ventilation air is achieved without using the heat pumps but instead with cold water from the subsurface. The ATES installation satisfies the building’s requirements for optimum heating and cooling, whereby a maximum temperature of 23 degrees will be achieved inside the sports halls during the summer months. Jaco: “An all-electric energy supply with as much as possible self-generated energy is the most future-proof solution. We, therefore, advised the application of an ATES installation instead of a heat pump. The ATES installation was installed in the ground to a depth of approximately 225 metres. The effect on energy consumption in the spring and summer, when cooling instead of heating is required, is that the electricity consumption for cooling with an ATES installation is 85% lower than with air heat pumps. This is because an ATES installation only requires energy for pumping, and the compressor for the heat pump does not have to be running to produce cooling. A beneficial solution for the number of operational hours and thus the lifespan of the heat pumps.”
How the Heat and Cold Storage system works The energy for heating rooms is generated by heat pumps that exchange energy with groundwater. The heat pumps upgrade the heating energy extracted from the subsurface to an operating temperature of 45 degrees Celsius. By extracting heating energy from the subsurface, the groundwater cools. This cold groundwater is then used during the summer months for cooling rooms. Therefore, cooling for the rooms and the ventilation air is freely available without having to use heat pumps. Exchanging energy using groundwater takes place at a reasonably constant groundwater temperature. The heat pumps are designed to work optimally at this temperature, and the efficiency of these pumps (SCOP) is high. Conversely, heat pumps that exchange energy using outside air typically have a much lower SCOP value.
The building can be optimally heated and cooled with the ATES installation.
A comfortable indoor temperature The sports halls are heated and cooled through climate panels. This is similar to a radiator on the ceiling and consists of a steel plate over which pipes run. In this case, the steel plate is perforated and becomes hot or cold depending on the season. An advantage of radiant panels is that they can maintain a room’s temperature during the nighttime hours, thus eliminating the need for fans, which again saves energy. Another advantage is that they react considerably faster than underfloor heating to varying loads (such as the number of people occupying the room). When a greater number of people occupy a hall, it naturally becomes warmer, and the radiant panels cool the room to the desired temperature.
The same applies the other way around. This is how the radiant panels ensure a comfortable climate for sports and exercise.
The building is equipped with a control system that regulates all climate equipment and ensures that the energy sources are used optimally. As a result, only the rooms in use are climatised. The control system is easy to operate for the building management, and all controls can be organised as desired. The installation is also equipped with an energy module. By way of an energy consumption trend analysis, omissions in technical installations, such as incorrect setpoints or incorrect operational times, can be identified.
Ventilation The building’s air conditioning units are equipped with high-efficiency energy recovery. To limit the transportation of ventilation air, the quantity per occupied area is regulated according to the CO2 content. By aligning the ventilation quantities to the required volume of air, the energy consumption of the fans in the air conditioning units is limited. In addition, the air conditioning units are situated close to the demand areas, which means the ductwork is relatively short and limited.
Sustainable lighting All fixtures in the sports complex have been realised with LED lighting. To limit energy consumption as much as possible, the lighting in each room is activated through presence detection. All lighting is switched off at fixed times via a sweep switch. The lighting is fully dimmable and automatically dims according to the type of use. For example, when the location is used for physical education purposes during the daytime, the lighting is set to 300 lux, for regular sports 500 lux and 750 lux for top-end sports.
An extremely leakproof building Jaco: “A fun fact that doesn’t have much to do with the technical installation work of Iv-Bouw, but which does influence the energy consumption of the building, is that the building is extremely leakproof. This means that hardly any air escapes through, for example, cracks and seams in the building’s exterior envelope. The legal requirement for leakproofness is a qv10 value of 0.4. Our team aimed for a value of 0.3 for De Altis. But because of the fine architectural detailing and the attention given to this during the implementation, it appeared after a test that De Altis boasts a leakproofness of 0.15, which is extremely leakproof. As a result, almost no outside air enters through the building’s exterior envelope, which results in lower energy consumption.”
Rightly proud The new sports complex was completed in April 2021. De Altis was officially opened in May 2021. Alderman of sport Björn Lugthart is proud of the result and rightly refers to it as an asset to Rijswijk. •