The Installer: Maximum efficiency heat generation systems in the rehabilitation of Building AA79

AA79 has obtained LEED® Platinum pre-certification for Core & Shell for energy efficiency and environmental sustainability, the highest level of sustainability certification awarded by the US Green Building Council.

Currently there are very few buildings with this certification worldwide, one of them is the AA81 building, which belongs to the same developer company, which obtained a 97-point rating, achieving first place in Europe and second in the world. This accreditation evaluates the sustainable strategies of office buildings according to their location, innovation, water consumption, energy efficiency, CO₂ footprint, air quality and materials management.Viessmann has manufactured and supplied the autonomous heat generation equipment containing the hot water boilers and the Vitosol solar thermal collectors for this unique building, whose installation project has been carried out and its implementation on site directed by Úrculo Ingenieros Consultores SA. This large restored building is well known in Madrid, it was the Telefónica I+D Headquarters, it is located next to the M30 next to the N-II highway and its main access is via Emilio Vargas street nº 4. It currently has more than 22,000 m² spread over seven floors above ground, with an open-plan distribution, excellent natural lighting, an active ventilated façade in extra-clear multilayer glass, with exterior and interior automatic blinds. It has technical floor,High-efficiency LED luminaires with minimum electrical consumption and reduced thermal load and point-to-point control system, with the most cutting-edge technology in telecommunications. It is a comfortable building, equipped with all the important services demanded by the people who currently work inside it (more than 1,500 people): kitchen, dining room, cafeteria, meeting rooms, shops, etc. Some characteristics of the modern facilities, to achieve great energy savings are its condensing boilers, magnetic levitation chillers, heat and cold emitters by induction system with passive cold beams that guarantee silent, efficient and very comfortable air conditioning, with inductors. and convectors.The primary air conditioning is carried out with Air Treatment Units equipped with heat and cold batteries. Renewable energy production is carried out with thermal and photovoltaic solar collectors for electrical self-consumption. It has a gray and rainwater recovery system for use in toilets and garden irrigation, achieving savings of more than 1,400 m³ of drinking water each year. The autonomous Viessmann Vitomodul-UTC heat generation equipment is responsible for providing the necessary heating in the building, it is located on the roof of the building and its enclosure is made of specific materials for outdoor installation. Contains the condensing boilers, with all the control and safety equipment necessary for an autonomous operating system.The boilers installed inside are two equal boilers, for Natural Gas fuel, Vitocrossal 300-635 kW model. These condensing boilers have a fumes-water thermal exchange body made of AISI 316-Ti Stainless Steel, for operation with variable water supply temperatures according to the outside temperature curve, without a low return temperature limit value, with a seasonal efficiency of 109%. referred to the PCI of the fuel. They contain a large volume of water, to achieve optimum modulating operation of your Weishaupt burners. For operation with variable water supply temperatures according to the outside temperature curve, without a low return temperature limit value, its seasonal efficiency being 109% referred to the PCI of the fuel.They contain a large volume of water, to achieve optimum modulating operation of your Weishaupt burners. For operation with variable water supply temperatures according to the outside temperature curve, without a low return temperature limit value, its seasonal efficiency being 109% referred to the PCI of the fuel. They contain a large volume of water, to achieve optimum modulating operation of your Weishaupt burners.

The heat generation equipment is located on the roof of the building and is made of specific materials for outdoor installation. WMG-ZM series installation that performs electronic combustion control with low emissions. They incorporate Vitotronic digital electronic regulation, with LON protocol for easy integration into the centralized management system. Under the design conditions of the project, the boilers work with very low water supply and return temperatures, achieving permanent condensation of the water vapor contained in the combustion gases, with the transfer of latent heat to the system. The temperatures of the combustion gases are very low, always below 70 ºC, minimizing thermal losses due to sensible heat in the fumes. By keeping the bodies of the boilers at a low temperature, thermal losses due to radiation and convection are also reduced, achieving great energy savings. The solar thermal installation to support the heating of the DHW, with a reduction in the energy consumption of the heat pump with CO₂ refrigerant, consists of eleven high-performance Viessmann solar collectors of the Vitosol 200T-SP2A vacuum tube type with a unit surface area of ​​3.19 m², with heat-pipe technology, mounted on the roof in a completely horizontal position, with a 25º inclination of the absorber and with South orientation. The radiation absorber plate that contains each glass tube has a copper tube inside which is a specific fluid with a very low boiling point, which carries out the condensation and evaporation process, releasing energy in dry contact to the installed duotec exchanger. in the tube connection box and through which the heat carrier fluid from the solar primary circuit circulates. Within each glass tube the vacuum has been made, to minimize thermal losses by convection from the absorber plates to the outside. This building-mounted solar installation provides more than 60% of the annual energy demand for heating domestic hot water. The control system installed in the building is of the BMS centralized technical management type, with EMS energy consumption management by water and energy meters, with more than 24,000 control points in the facilities to guarantee maximum energy savings with the best comfort for people. z Weishaupt burners with Vitotronic perform electronic combustion control with low emissions. The solar installation mounted in the building contributes more than 60% of the annual energy demand for heating domestic hot water. This building-mounted solar installation provides more than 60% of the annual energy demand for heating domestic hot water. The control system installed in the building is of the BMS centralized technical management type, with EMS energy consumption management by water and energy meters, with more than 24,000 control points in the facilities to guarantee maximum energy savings with the best comfort for people. z Weishaupt burners with Vitotronic perform electronic combustion control with low emissions. The solar installation mounted in the building contributes more than 60% of the annual energy demand for heating domestic hot water. This building-mounted solar installation provides more than 60% of the annual energy demand for heating domestic hot water. The control system installed in the building is of the BMS centralized technical management type, with EMS energy consumption management by water and energy meters, with more than 24,000 control points in the facilities to guarantee maximum energy savings with the best comfort for people. z Weishaupt burners with Vitotronic perform electronic combustion control with low emissions. The solar installation mounted in the building contributes more than 60% of the annual energy demand for heating domestic hot water. The control system installed in the building is of the BMS centralized technical management type, with EMS energy consumption management by water and energy meters, with more than 24,000 control points in the facilities to guarantee maximum energy savings with the best comfort for people. z Weishaupt burners with Vitotronic perform electronic combustion control with low emissions. The solar installation mounted in the building contributes more than 60% of the annual energy demand for heating domestic hot water. The control system installed in the building is of the BMS centralized technical management type, with EMS energy consumption management by water and energy meters, with more than 24,000 control points in the facilities to guarantee maximum energy savings with the best comfort for people. z Weishaupt burners with Vitotronic perform electronic combustion control with low emissions. The solar installation mounted in the building contributes more than 60% of the annual energy demand for heating domestic hot water. z Weishaupt burners with Vitotronic perform electronic combustion control with low emissions. The solar installation mounted in the building contributes more than 60% of the annual energy demand for heating domestic hot water. z Weishaupt burners with Vitotronic perform electronic combustion control with low emissions. The solar installation mounted in the building contributes more than 60% of the annual energy demand for heating domestic hot water.

Cipriano Colino

Viessmann Business Engineer