, Faculty of Architecture Electric Power Demand of Buildings COMPLEX 1 & DIPLOMA Design Aid András Majoros, Emil Vetési, Levente Filetóth Edited by Levente Filetóth 2014 February
TABLE OF CONTENTS CALCULATION AND DESIGN TASK 3 DELIVERABLES 3 1. PROBABLE ELECTRIC POWER SUPPLY OF THE BUILDING 4 1.1. TRANSFORMER STATIONS 6 1.2. BACKUP AND EMERGENCY POWER SUPPLY SYSTEMS 9 1.3. PHOTOVOLTAIC PANELS 12 2. CALCULATING THE ELECTRIC POWER DEMAND OF THE PROJECT 13 2.1. ELECTRIC POWER DEMAND OF NON- RESIDENTIAL BUILDINGS 13 2.2. ELECTRIC POWER DEMAND OF RESIDENTIAL- TYPE BUILDINGS 17 3. REQUIREMENTS OF ELECTRIC SWITCH- ROOMS 18 Épületek villamos ellátása, KOMPLEX 1. és DIPLOMA tervezési segédlet 2.
Calculation and Design Task The goal of the electric power demand calculations are to forecast the method of the electric supply of the building and to design and determine the corresponding required electrical utilities. The following is an approximate electric power demand calculation. The actual, realized electric power demand of the building may differ up to approximately 25% compared to the results calculated here. At the early design stages we do not have detailed and precise information about the building to perform more accurate calculations. The purpose of this electrical calculation is to determine the probable electric supply method and to forecast the area and the number and the area of the corresponding electric switch-rooms, battery rooms, transformer rooms or to host diesel power generators, etc. Deliverables Please complete the following, specific tasks throughout the semester: 1. Describe the probable method of the electric power supply of the building (this should be determined by the preliminary submission of the design project). 2. Calculate the electric power demand of the building. 3. Determine the number and size of the rooms and areas required for the electric power supply. Please indicate these rooms in the architectural design documentation. Please submit the lighting design deliverables as part of the "Building Energetics and Services" booklet. Épületek villamos ellátása, KOMPLEX 1. és DIPLOMA tervezési segédlet 3.
1. Probable electric power supply of the building The probable electric supply method of the building depends on: the expected sum of the simultaneous electric power demand, and the site and the surroundings of the building. The site of the building usually determines its electric power infrastructure and supply methods. The electric power infrastructure depends on the building density of the plot (downtown, suburbs, rural, etc.). The structure and the density of the plot determine the electrical power demand [kw/km 2 ] of the area, which forecasts the probable electrical infrastructure as well. The electrical devices in the buildings are utilizing 0.4 kv (400/230 V) network. The power network is underground cable network in case of dense downtown areas and air cable network supported by columns in case of suburbian and rural areas. This electrical network is always supplied by a transofrmer. The transformer supplied by a mid-range electrical network: in dense, downtown areas the transformer is supplied by a 10kV electric power network, this is a so called 10/0.4 kv transformer. In such areas the low- and mid-power electrical networks are underground cable infrastructures, in suburbian and rural areas the transformer is supplied by a 20kV air-cable power network, this is a so called 20/0.4 kv transformer. In such areas the low- and mid-power electrical networks are open air cable infrastructures supported by columns. The electric power demand of the building may vary between the range of a couple of 10kW and couple of 100kW, depending on the size and the function of the building. If the specific power demand of the building is relatively small, it can be considered to provide the electric power supply using the available 0.4 kv underground- or overhead line network. In such case the existing electric network must have adequate free capacity to supply the demand of the new building. The actual value of this realtively small demand might vary depending on the location and on the building in the practice such information must be provided by the corresponding electric authorities. Épületek villamos ellátása, KOMPLEX 1. és DIPLOMA tervezési segédlet 4.
When developing the semeseter design projects, we consider, that the required electric power demand can be provided using the 0.4 kv network, if the forecasted electric power consumption of the building is bellow: 200 kw in case of downtown area, 100 kw in case of suburbian, rural area. Red text: 20kV air cable; Blue text: 0,4kV air cable; Green text: Phone, TV cable The location and cable interface of the transformer may vary, the actual power supply solution depends on the type of the mid-range electric power network and the proposed location of the transformer station (inside or outside of the building). The followings must also be considered and elaborated when deciding about the power supply of the building: 1.1. Forecast the necessity of a transformer station: if a transformer station is requied, its location and charactersitics must be considered when creating a transformer station inside or outside of the building, 1.2. Decide about emergency and backup power supplies, 1.3. Consider using renewable energy (sun, wind or water) to generate electricity. Épületek villamos ellátása, KOMPLEX 1. és DIPLOMA tervezési segédlet 5.
1.1. Transformer stations In dense, downtown areas where the transformer is supplied by a 10 kv electric power network: inside the building in a transformer room, outside of the building in a dedicated, prefabricated, uni-body transofmer station. In suburbian and rural areas where the transformer is supplied by a 20 kv overhead line network: as a column transofmator placed in a public area, outside of the building in a dedicated, prefabricated, uni-body transformer station (in such case a 20kV cable connection is required between the transofmer and the building), inside the building in a transformer room (in such case a 20kV cable connection is required between the transofmer and the overhead line network). Transformer stations outside the building (above ground and underground) Column transformer stations Épületek villamos ellátása, KOMPLEX 1. és DIPLOMA tervezési segédlet 6.
The main sizes of a 630 kva-es transformer: 140 x 95 x 160 cm, weight: 2000 kg. Please consider the following rules when designing a transformer station inside the building: the transformer station must be located on the ground floor or on the first basement level, the transformer station must be located on the external building envelope (one of the walls of the station must be ab external wall), the floor area of a station is about 10 m 2, the internal headroom of the station must be at least 2,6 m. If the transformer station is located on the ground floor only one external door must be provided towards the exterior of the building. If the transformer station is located on the first basement level, a 1,4 m wide service well must be provided to access the station from the outside. Besides the service well, an internal door must also be provided to be able to access the transformer station from the inside of the building. Floor plan schemes of a 630 kva transformer station (must be located on the ground floor or on the first basement level of the building, along an exterior wall) Épületek villamos ellátása, KOMPLEX 1. és DIPLOMA tervezési segédlet 7.
Floor plan and section sketch of a 630 kva transformer station Épületek villamos ellátása, KOMPLEX 1. és DIPLOMA tervezési segédlet 8.
1.2. Backup and emergency power supply systems Depending on the function of the building, and the possible danger caused by the absence of electric power provided from the grid (hospitals, concert halls, factories, airports, fire stations, etc.), a backup and/or an emergency power supply might also be necessary. These are the main criterias to be considred when deciding about emergency and backup power supply systems: the power demand of those electric devices must be calculated that requires backup power, the maximum allowed time duration must be determined that is allowed between the power failure of the grid and the initialization of the backup system (how long can de building be without electric power: only milliseconds, or a couple of minutes?). Based on the above criteria, there are two main type of power backup systems batteries and diesel-engine powered generators. Batteries must be used if it is important to provided uninterrupted power supply (UPS) for the building. Diesel power generators require about one minute initilazation time. Diesel engine powered generators Épületek villamos ellátása, KOMPLEX 1. és DIPLOMA tervezési segédlet 9.
Floor plan and section of a diesel powered generator room located inside the building Épületek villamos ellátása, KOMPLEX 1. és DIPLOMA tervezési segédlet 10.
These are the main rules to consider when designing a diesel-engine powered generator: the generator can be located inside the building or outside, as a standalone unit, if it is inside the building, it is recommended to locate the generator close to the external building shell (easier maintenance, noise, exhaust gases, etc.) the noise of the generator, the diesel fuel tank and the heavy weight of the engine must all be considered. Approximate room size of a diesel generator inside the building: 20 kva unit: 4 m x 6 m, openings cca.: 1,8 m 2, 1600 kva unit: 5 m x 12 m, openings cca.: 10 m 2. The following tables presents various battery types and their corresponding sizes and weights. Power [VA] Dimensions [mm] Weight [kg] A H B m 600 430 630 160 49 1000 430 630 160 49 1600 430 630 160 49 2200 550 630 160 63 3000 550 630 160 63 Power [kva] Dimensions [mm] Weight [kg] A H B m 50 1200 2200 800 1000 80 1200 2200 800 1100 120 1200 2200 800 1300 170 1200 2200 800 1500 Batteries must have a well ventilated, dry room where the temperature is between +5 and +30 C. A battery charging station must also be located in a separate room, next to the batteries. The charging station requires about 1,5 m 2 room. Épületek villamos ellátása, KOMPLEX 1. és DIPLOMA tervezési segédlet 11.
1.3. Photovoltaic panels Photovoltaic - or PV - panels can be used to use the renewable solar energy to generate electric power. The typical "cell" size of the PV systems are cca. 125x125 mm. These cells are usually forming a "panel", ready to be installed on the building. PV systems ususally generate 12V or 24V direct current (DC), therefore a so called "inverter" must also be installed to provide 220V (or 110V), 50Hz alternating current (AC). PV panel installation examples The capacity of the PV panels determined by the number of installed PV panels: Sizes of a typical PV panel: cca. 80 cm x 150 cm, Thickness: cca. 4-6 cm, Weight: cca. 15-30 kg. Generated electricity: 160-280 W/panel. In Hungary it is recommended to install PV panels oriented towards the South, with an approx. 45 degrees inclination/ PV panel installed on a pitched roof with tiles covering Épületek villamos ellátása, KOMPLEX 1. és DIPLOMA tervezési segédlet 12.
High visual demand: 20 W/m2, such functions and rooms would be: exhibition rooms, cosmetics, etc. A [m 2 ]: sum of floor areas of the rooms having similar visual demand. 2.1.2. HVAC & Mechanical systems The building or building parts might be equipped with heating, ventilation, air conditioning and similar systems and/or equipment (pumps, engines and motors, etc. are connected to HVAC), their overall power demand is: P HVAC : please refer to the electric demand chapters of the heating, ventilation, water-supply, air-conditioning design aid, also available as a PDF download from the department website. 2.1.3. Technology & Equipment The overall electric power demand of all other technological electric devices and equipment in the building must be also considered and calculated (electric cookers, elevators, computers, coffee machines, etc.), their overall power demand is: P technology : please develop a detailed list of all electric devices and equipment of the building to determine their power demand with the help of the consultant. The following table lists some typical electric devices and equipment, you may use these values and also add project specific devices elements if necessary! Épületek villamos ellátása, KOMPLEX 1. és DIPLOMA tervezési segédlet 14.
Buffet and tea-kitchen Coffe and tea maker 0,7 1,2 Grill 0,7 1,0 Microwave owen 0,5 2,0 Toaster 0,8 1,6 Cattle 2,0 2,5 Turmix machine 0,4 Fridge 0,2 Air exhauster 0,2 0,3 Deep freezer 0,5 Generic kitchen Dishwasher 3,5 5,0 Freezer 0,2 Kitchen robot machine 0,2 0,6 Grill 0,8 3,3 Meat grinder 1,0 Other equipment 2,0 3,0 Indutrial kitchen Electric cooker 5,0 12,0 Dishwasher 3,0 8,0 Electric boiler 12,0 Electric frier 5,0 Freezer 0,5 Dishwasher 3,0 8,0 Freezer cupboard 0,8 1,2 Other equipment 3,0 6,0 Elevators, escalators Hydraulic elevator (max. 30 m), residential building 7,0 28,0 Hydraulic elevator (max. 30 m) public building 10,0 75,0 Wire-suspended elevator (max. 30 m) residential building 2,0 8,0 Wire-suspended elevator (max. 30 m) public building 3,0 25,0 Wire-suspended elevator without machinery room (max. 9 m) 2,2 Elevator without machinery room (max. 9 m) 1,1 Small industrial elevator (250 kg) 1,2 1,5 Panorama elevator (1250 kg) 25 31,0 Industrial elevator (2000 kg) 5,0 7,0 Escalator (max. 40 m) 7,0 90,0 Escalator (max. 150 m) 5,0 20,0 Hospital elevator (2500 kg) 6,0 8,0 Most of the elevators require an additional, standalone machinery room with specific location. Please ask your consultant for further details! Épületek villamos ellátása, KOMPLEX 1. és DIPLOMA tervezési segédlet 15.
Doctors' examination room Dentist chair 0,2 0,5 Dentis X-Ray 2,0 Hand and gloves cleaner 0,02 Mobile X-Ray 13-15 Light therapy equipment 0,1 0,2 X-Ray viewer 0,05 Water cleaner 0,05 Hospital Surgeon small equipment 0,7 0,8 Lab drier 0,5 1,0 Labor equipment 0,1 1,2 Air handling devices 0,1 0,2 Diagnostic X-Ray 55,0 Surgeon equipment 8 10,0 Swimming pool Hydro-pool (3-5 person) 2,5-6,0 Sauna (3-5 person) 4,5 Hydro-pool (6-8 person) 6,5-8,5 Sauna (8-12 person) 22,0 Hydro-pool with heater +3,0-5,0 Sauna with heat-sinker 6,0 Solarium 9,0-11,0 Infra sauna 1,5-2,5 Finnish-sauna (2-3 fő) 3,0 Other equipment Washing machine 2,2 3,3 Sewing machine 0,1 2,0 Washing machine with drier 3,3 Hair drier 0,4 2,0 Drier 2,1 3,3 Vacuum cleaner 0,2 1,6 Office and IT equipment Smoke, fire alarm and similar systems (smoke, fire, secutiry, etc.) 0,5-5,0 Consumer electronic devices (tv, video, CD/DVD-players, speakers, etc.) 0,1-10,0 Security systems 0,5-2,5 Projetors 0,2-0,6 Computer systems (computer, scanner, printer, etc.) 0,6 1,2 Épületek villamos ellátása, KOMPLEX 1. és DIPLOMA tervezési segédlet 16.
2.2. Electric power demand of residential-type buildings The electric power demand of residential buildings and other buildings with residential units (such as hotels or hospitals) can be determined using a slightly different manner. This calculation method can be used for building having at least one residential unit. Such buildings can be divided into two main parts: Residential units: their electric power demand is P residential, and Non-residential areas: their power demand is on-residential. In case of residential units we do not investigate and calculate all the electric devices and equipment in detail, but we consider these units as one single equipment and we determine its power demand using statistical data with the help of the following formula: P residential = P residential units + on-residential. where: P residential = e unit n P unit, where n: the number of the flats or residential units, P unit : the electrical demand of the residential unit: unit with electric cooker: 11,04 kw, unit without electric cooker: 6,9 kw, hotel room: 2,3 kw, weekend house: 3,3... 7,36 kw. e unit : simultaneity coefficient: e unit = e = 0, 2 + 0,8 n on-residential : please read chapter 2.1. for further details. Épületek villamos ellátása, KOMPLEX 1. és DIPLOMA tervezési segédlet 17.