Annals of Warsaw University of Life Sciences - SGGW Forestry and Wood Technology 85, 2014: 40-44 (Ann. WULS - SGGW, For. and Wood Technol. 85, 2014) The analysis of the energy demand for heating and cooling of the house built on the basis of the traditional Canadian wood-frame construction MARIUSZ CYRANKOWSKI, JACEK WILKOWSKI, PIOTR PODZIEWSKI, KAROL SZYMANOWSKI, DAGMARA CHLUDZIŃSKA Faculty of Wood Technology, Warsaw University of Life Sciences - SGGW Abstract: The analysis of the energy demand for heating and cooling of the house built on the basis of the traditional Canadian wood-frame construction. This study shows calculation of demand for power needed for heating and cooling of a house built in compliance with Canadian wood-frame construction technology. Conducted calculations prove that the house erected by traditional Canadian wood-frame construction technology shows lower demand for thermal power than the brick building, while energy consumption on cooling is higher. Keywords: masonry house, Canadian wood-frame construction, energy effectiveness, demand for thermal power PURPOSE AND SCOPE OF THE WORK The aim of the work is to calculate demand for energy needed to heat and cool single family house built on the basis of traditional Canadian wood-frame construction technology using the simplified hourly method. Calculations were conducted in accordance with PN-EN ISO standard 13790:2009 Appropriable energy properties of buildings. Calculation of energy consumption on heating and cooling. The model was based on the data of typical meteorological year, which are available on the website of the Ministry of Transport, Construction and Maritime Economy for Warszawa-Okęcie weather station. MATERIALS AND METHODS Calculation of energy consumption on heating and cooling were performed using hourly method, which mathematical model is simplification of the image of internal and external environment parameters changes used by building energy simulation. Using this mathematical model it is possible to determine the value of heating and cooling power at any time from 8760 hours of typical meteorological year. The internal space of a building is divided into zones, where the parameters of thermal comfort are to be maintained. Decrease or excess of temperature determines the start of heating or cooling system. Values of internal air temperature are variable and determined at any hour of the year. Determination of the following factors is required for the calculations: heat loss through transparent and opaque partitions, coefficients of heat loss through inner surfaces and coefficient of ventilation heat loss. In the simplified hourly method both heat gains and losses through all the exterior coverings (roof, floor on the ground, doors, windows) are taken into account in view of the heat capacity, internal heat gains from people staying in the appropriable area and from electrical equipment, heat loss by long-wave radiation. The calculations are carried out for each of the 8760 hours of the year based on the Warszawa- Okęcie weather station data. The calculated heat balance determines momentary energy consumption on warmth and cold. Access data to the model were based on the technical data of the building, while the using schedule was drawn up based on a typical daily schedule of a family consisting of four people (Narowski, 2013). 40
Table 1. Technical data of a building erected by Canadian wood-frame construction technology. INITIAL DATA Location Warsaw Orientation S Length 16,24 m Width 7,84 m Number of floors 2,00 - Height of floors 4,33 m External temperature -18,00 C Heat transfer coefficient of the external walls 0,176 W/m²K of the external doors and windows 0,600 W/m²K of the roof 0,123 W/m²K of the floor on the ground 0,148 W/m²K Construction of the building light Ventilation multiplicity of exchanges 0,60 1/h Table 2. Characterisation of a building erected by Canadian wood-frame construction technology. Characteristics of the building Length A 16,24 m Width B 7,84 m Number of floors 2,00 - Height H 8,66 m Cubic capacity 897 m³ Usable area 153,910 m² U s 0,176 W/m²K Computational transfer coefficients U ok 0,600 W/m²K U str 0,123 W/m²K U pod 0,148 W/m²K Multiplicity of exchanges 0,60 1/h Number of persons 4 os. Volume of air exchanged Computational internal temperatures 538,2 m³/h Ө int, H, set 20 C Ө int, C, set 26 C coefficient of air repossession by convexion h is 3,45 W/m2K ratio of partitions to floor A at 4,5 - effective are of thermal mass A m 318,304 m2 heat capacity C m 199312794,56 J/K 41
RESULTS Computational thermal power consumption needed to heat the air for the building erected on the basis of Canadian wood-frame construction technology is 1429,79 kwh higher than for a passive house with enhanced thermal insulation of external partitions, wood-based materials and constructional solutions to reduce heat loss through thermal bridges. The power supplied to the building [kwh]*10-1 Internal air temperature C External temperature Graph 1. Energy consumption in a function of internal and external temperatures of the building erected by Canadian wood-frame construction technology without the use of sunshades (Source: Own elaboration). At the same time the amount of energy required for heating was 648,85 kwh lower than in comparison to the traditional brick building using hollow brick and thermal insulations made of 20-cm thick expanded polystyrene. Table 3. Summary of computational thermal power demand for a house built of wood-frame construction without the use of sunshades. Heating Cooling 4420,43 kwh 11553,46 kwh 28,72 kwh/m 2 75,07 kwh/m 2 42
The power supplied to the building [kwh]*10-1 Internal air temperature C External temperature Graph 2. Energy consumption in a function of internal and external temperatures of the building erected by Canadian wood-frame construction technology with the use of sunshades (Source: Own elaboration). Table 4. Summary of computational thermal power demand for a house built of wood-frame construction with the use of sunshades. Heating Cooling 4459,32 kwh 960,98 kwh 28,97 kwh/m 2 6,24 kwh/m 2 CONCLUSIONS On the basis of the results of the conducted calculations the following conclusions has been drawn: 1. The house built on the basis of the Canadian wood-frame construction shows lower demand for thermal power than the brick house. 2. The house built on the basis of the Canadian wood-frame construction has shown the biggest energy consumption on cooling. REFERENCES: 1. Narowski P., 2013: Procedura obliczania rocznego zapotrzebowania na energię do ogrzewania i chłodzenia, Materiały do ćwiczeń z Fizyki Budynków, Wydział Inżynierii Środowiska Politechniki Warszawskiej 2. Chludzińska D., 2013: Analiza porównawcza zapotrzebowania energetycznego na ogrzewanie i chłodzenie dla różnych typów domów jednorodzinnych. Praca magisterska. Warszawa 3. PN-EN ISO 13790: 2009 Energetyczne właściwości użytkowe budynków. Obliczenie zużycia energii na potrzeby ogrzewanie i chłodzenia 43
Streszczenie: "Analiza zapotrzebowania energetycznego na ogrzewanie i chłodzenie domu wzniesionego w oparciu o tradycyjną technologię szkieletu kanadyjskiego". W pracy obliczono zapotrzebowanie na moc potrzebą do ogrzewania i chłodzenia dla budynku mieszkalnego wzniesionego tradycyjną technologią szkieletu kanadyjskiego. Po przeprowadzonych obliczeniach stwierdzono, iż dom postawiony według tradycyjnej technologii szkieletu kanadyjskiego wykazuje niższe zapotrzebowanie na moc cieplną niż budynek murowany, natomiast zużycie energii na cele chłodnicze jej wyższe. Corresponding authors: Mariusz Cyrankowski, Jacek Wilkowski, Piotr Podziewski, Karol Szymanowski, Dagmara Chludzińska Faculty of Wood Technology, Warsaw University of Life Sciences - SGGW 159 Nowoursynowska St. 02-776 Warsaw,Poland e-mail mariusz_cyrankowski@sggw.pl e-mail: jacek_wilkowski@sggw.pl e-mail: piotr_podziewski@sggw.pl e-mail: karol_szymanowski@sggw.pl 44