GENERAL DESCRIPTION OF THE BUILDING AND PROGRAM
In 2003, the new building of the Cultural Centre that housed a music school and an auditorium theatre was inaugurated. The last phase was to extend the Cultural Centre with a new municipal library, an entities hotel and complementary services for the theatre-auditorium.
An adjacent plot close to the theatre was available for the expansion of the Cultural Centre, a 3.773 m² plot, depressed in relation to the surrounding streets. The original library had insufficient surface to ensure a good library service and all town entities were scattered around the village in different premises.For all these reasons,the new Cultural Centre was designed to accommodate a single library building, an entities hotel, a theatre-auditorium and the school of music.
The overall objectives were to provide the municipality with a library according to the current parameters of a public library, create a hotel of entities to share space and resources in order to optimize surfaces, improve cultural facilities and expandthe municipality premises of the theatre- auditorium with storerooms, dressing rooms and rehearsal rooms.
A hotel of entities has the function of bringing together in one building all cultural institutions, associations, folk groups, sports clubs... that bind civil society of the town. This is to optimize resources and spaces for a rational and effective use of the public budgets. All the entities can use the facilities offered in the building: meeting rooms, offices, restrooms, etc., plus equipment and supplies (phones, copiers, fax machines, computers...)
The new Cultural Centre was build as a single volume of three floors, open to the future square, that houses the program of the entities hotel, the library and the expansion of the dependencies of the auditorium.
Due to the steep incline of the site, the building is partially buried and taking advantage of the slope of the adjacent streets people can access the library and the hotel entities independently and directly from the public space.
The communication between the new and the existing building is possiblefrom to the second floor, from the storerooms of the theatre and the canteen, which acts as a link and as a generator of activity.
The two points of communication between the buildings (new and old volume) generate a courtyard, suitable for meeting place and reading area and which provides lighting apart from connecting the three floors of the building and has the function of visual connection between all parts of the building
The building was built in five consecutive phases, still not finished, remaining the urbanization of the outdoor area, dedicated to public space.
Library The access to the library, by the public square, divides the adults and the children's library through a large triple-height hall that visually connects all the levels of the building.
On the ground floor, in relation to the courtyard and the square, there are the information and borrowing areas, magazines, music and Internet. On the first floor there are a training classroom and the general fund area, opened to a large longitudinal double-height space over the ground floor.
Entities hotel On the first floor, with own access from the side street, there is a multipurpose room and a training classroom, to be shared between the library and the entities hotel, another room and a small storeroom. On the second floor there are two small musical spaces, two more rooms, 6 offices for the entities and another storeroom.
Theatre services On the second floor, the existing theatre additional spaces are expanded with new warehouse, a rehearsal room and a dressing room with bathroom inside. These new units also have a new access direct from the side street.
The building is outlined considering energy efficiency criteria to ensure a reduction in energy demand and good energy efficiency, achieving a high efficiency building.
The facade of the square, facing west, is presented as a double skin and it is set up by double glasses with low emissivity inside and micro perforated folded overlay on the outer layer to ensure sun protection.
The north and south facades, corresponding to the endings of the building are very opaque and made with exposed concrete. The facade facing the inner courtyard is finished with corrugated iron. All opaque enclosures have 16 cm of insulation and thermal bridges are non-existent.
The project began with the objective of achieving a sustainable energy behaviour.
Strategy: 1 - Minimize demands. 2 - Improve the efficiency of the systems. . 3 - Optimize the use and subsequent management.
1 - Minimize demands.
The building, understood as an architectural container, was constructed in order to minimize energy demands, with special attention to the treatment of glass facades and its protections, as well as specific isolates of the roof with 20cm, to improve the certification.
2 - Improving the efficiency of the systems.
The library building has an eco and comfortable air-conditioning that reduces CO2 emissions, which achieves savings of up to 60 % when compared with more conventional systems such as conventional electric heat pumps.
2.1 Geothermal system
The interior of the building is heated by a low enthalpy geothermal system consisting of three major subsystems: - Heat exchanger, which extracts heat from the subsoil or evacuates the heat of the building. - Heat pump, which transfers heat between the heat exchanger of the subsoil and the distribution system of the building. - Distribution System, which distributes heat or cold to the premises depending on the needs.
2.2 Heat exchanger
The heat exchanger has its source buried in a valve, where there is a pumping manifold and a return one, from where 27 wells of 150 meters deep each come up.
The wells provide, in the initial tranche, of 8 linear metres of steel pipe to ensure the stability of the ground during drilling tasks. The collectors are 125 mm diameter and are fitted with hydraulic balancing valves Setter trim control with bypass. All the hydraulic circuit is filled with a mixture of water with pure monoethylene glycol, so that the final mixture freezing set between -15 ° C and -18 ° C. Once filled and placed the probes, the remaining space between the probes and the walls of the neighboring land is filled with a GeoticMortermaterial, injected from the bottom of the hole to ensure full filled, ensuringa thermal conductivity of λ ≥ 1 W / mK .
2.3 Heat Pump Production of cooling/heating is achieved using 2 units of high efficiency geothermal heat pumps,CLIVET brand, WSHN- XEE 452, for indoor installation of 120 KW in nominal terms, with the following benefits in working conditions:
- Cooling capacity. 139 KW with water 7/12 ° C - condensing at 35 /30 º C - Heating capacity. 121 kW with water 45/40 ° C – evaporating at 0/-3 º C - A 4-pipe system for simultaneous and independent production of cold and heat.
These units, with a self-controland self-regulation in its interior, maintaintwo reservoirsof inertia at constant temperatures: one of heat with water at 45 ° C and another of cold water at 7 ° C. The surplus of heating/cooling produced by heat pumps will go to the geothermal hydraulic circuit.
The high COP of the heat pump allows considerable energy savings and efficiency.
With this system of heating generation we managed to comply with the HE-4 section of the Technical Building Code without placing solar thermal collectors for SHW production, since the necessary energy supply is achieved with the use of the renewable energy of the geothermal system.
2.4 Distribution circuits
The cooling/heating pipes are distributed according to the following independent circuitry:
- Cold distribution circuit for primary air conditioners - Cold UTAs distribution circuit for indoor air treatment - Primary circuit of underfloor heating - Heat distribution circuit for primary air conditioners - Heat UTAs distribution circuit for indoor air treatment
The circulator pumps installations are located on the roof.
The whole building has units of local air treatment, which receive and distribute the treated primary air of the units placed on the roof.
The double height ground floor hosts the most special space of the building, the Library.
The room height of the library makes necessary the use of the underfloor heating, to provide adequate comfort to the users without heating such a huge volume, improving the efficiency of the system.
From the roof, where the technical room, the heat distribution circuit go out and will arrive to the underfloor heating lockers on the ground floor. The control points and the start circuits under the floor are placed in cabinets.
Each circuit, associated with a control area, will have a two-way motorized valve to open/close the passage of fluid to the circuit area in terms of the thermal requirements of each zone detected by probes.
2.5 Air Treatment
The indoor air conditioning system of the building consists of 4 units of primary air treatment , in the cover, incorporating regulatory heat recovery sections and have a yield of 70 %. There are sorting filters Eurovent EU-4 , EU- 6 and EU-8 as well as battery heat exchanger with a three-way valve for regulation.
Each areas or rooms are provided by climate control, UTA, for a final treatment. The two-parts system with primary and terminal air conditioners, allow the optimization of consumption energy and more stable temperatures of pumping and extraction.
All pipes made with galvanized sheet are sized to provide a constant load loss. The fans are provided to overcome the higher worst loss taking into account the terminal elements of diffusion.
All grilles/diffusers as well as branch lines to each AHU (Air Handling Unit), have their corresponding damper to flow adjustment in order to control independently each of the areas of the building or premises. This control allows a perfect balance with a consequent energy saving.
The air distribution ducts provide thermal insulation for not to exceed the 4% of heat loss of the transported power, being that enough to prevent condensation.
The central regulation and control of the entire heating and ventilation, as well as DHW is in the technical area of the roof.
3.-Optimising the use and subsequent management .
The building has a management system to control all the parameters that enable a comprehensive facilities management and adaptation to seasonal variations (summer mode/winter mode), as well as the use timetable and maintenance schedule.
The distribution of air conditioners allows proper adjustment of primary airflow and consumption. All equipment for processing primary air are equipped by frequency controllers for the final adjustment of the air flow. That makes possible minimizing theconsumption with the proper implementation of the system and its subsequent maintenance.
The management system has 53 analogue inputs and 28 digital ones, as well as 10 analogue outputs and 150 digital ones. The system is capable of driving most systems, using the start/stop fans, circulator pumps and production equipment.
Consequently, that allows the design and subsequent programming of all “on” switch, adjusting opening and closing times.
All field elements allow appropriate management of each seasonal period and the energy needs of each space according to their use temperatures, allowing a rationalization of energy and a corresponding improvement in energy efficiency.