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Contract No.: 0SQ77-00170, prepared for National Research Council of Canada

This Note presents a modification of the degree-day method of calculating annual heat requirements. This modified method termed "Net Annual Heat Loss Factor" allows the designers to take more accurate account of factors such as the solar radiation incident on a building surface. House heat loss components calculated by the two methods are compared.

prepared for National Research Council of Canada, préparé pour le Conseil national de recherches du Canada

Le chauffage du sol par l’intermédiaire de tuyaux enterrés modifie profondément les champs de température dans la zone racinaire des plantes. Pour des espèces comme l’iris, la tulipe et le glaïeul, le chauffage se traduit par une accélération de la croissance et du développement des plantes, tant que les futurs organes aériens sont situés sous la surface du sol. Par contre, pour le lis, dont l’apex reste très peu de temps sous la surface du sol, l’effet du chauffage du sol est pratiquement nul ; l’influence du chauffage du sol est donc directement liée aux caractéristiques de croissance des plantes. Sur le plan de la qualité des plantes, on observe un antagonisme entre la qualité et la précocité., Soil heating by means of buried pipes greatly modifies the temperature range in the root zone of plants. In the case of iris, tulip and gladiolus, soil heating leads to an acceleration of growth and development of the young plants, as long as the top of the stem remains below the soil surface. Soil heating has practically no effect on lily, whose stem stays only a short time below the soil surface. The influence of soil heating depends mainly on the growth characteristics of the plant. An opposition between quality and earliness has been observed.

A program designed to simulate the performance of a multi- row finned-tube heat exchanger during cooling and dehumidification is presented. It is limited to the simulation of circular tube banks (four rows or more) fitted with either circular or continuous flat fins. The input data to the program are the pertinent physical dimensions and thermal characteristics of the heat exchanger, together with the inlet conditions of the moist air and the chilled water. The air and chilled water outlet conditions, the sensible and latent heat loads, and the wet and dry surface areas are calculated for each set of input data.

In December 1977, an air-source heat pump was installed in one of the Mark XI energy conservation research houses in Ottawa, Canada. The system was purported to incorporate a number of features recognized as important in a northern climate heat pump. Monitoring of system performance began in December 1978 and was completed in May 1980. During this period, the heating energy supplied and consumed by the system under both normal operation (in response to the house load) and steady-state conditions (artificially induced load) was measured. Information on the frequency, duration and energy consumption of the defrost cycle was also recorded. This Research Note reports on the results of this study.

Contract No. 0SR77-00140, prepared for National Research Council of Canada

Contract No. 0SX79-00079, prepared for National Research Council of Canada

Experiments were performed to determine the net energy contribution of a domestic water system to the internal heat gain of a house. Four water usage profiles and two cold water supply temperatures were considered. For a typical water consumption schedule, it was found that, apart from the hot water tank standby losses, heat gains to the house from water usage are very small.

Contract No. 0SX80-00062, prepared for National Research Council of Canada

An effective, cheap and simple heating device was designed by INRA (Orléans) to prevent flower frost damages in outdoor controlled crosses. It consists of a small electrical resistance which is inserted in each individual pollination bag. A field experiment conducted on larch trees showed that not only the number of living flowers is significantly increased after a frost period but also the number of full seeds per cone., De manière à éviter les dégâts de gelée lors des croisements contrôlés en champ,l'INRA d'Orléans a mis au point un système de chauffage individuel des sacs de pollinisation. Il s’agit d’une résistance électrique que l’on glisse dans les sacs. Une expérience conduite dans un parc à clones de mélèzes a montré l’efficacité du système ; il permet à un coût très réduit, d’augmenter significativement non seulement le nombre de fleurs vivantes après une période de gel sévère, mais aussi le nombre de graines pleines par cone.

A study was carried out on energy consumption in a number of Saskatchewan homes where natural gas and electricity are used for cooling, lighting, water and space heating and other domestic needs. Particular attention was given to energy use for space heating. In some parts of Saskatchewan, the Saskatchewan Power Corporation provides both natural gas and electricity to homes. Their records of consumption in about 1000 Regina homes in five districts within the city were used in this study. Annual average consumptions per house were found for each district. These ranged from 200 GJ (55 MW.h) to 235 GJ (65 MW.h). The rate at which purchased energy (natural gas plus electricity in these houses) is used varies with the season of the year, primarily owing to space heating requirements. When purchased energy consumption is plotted against heating degree-days, the relationship is usually nearly linear. The slope of this line and its ordinate intercept constitute an energy consumption characteristic for the house. This characteristic is affected by a variety of factors, including the heat loss characteristics of the house, the furnace efficiency and solar heat gain., Shelter : Proceedings of the 91st Annual Meeting of the Engineering Institute of Canada: 15 May 1977, Jasper, Alb., Canada

Contract No. 0SX83-00004, prepared for National Research Council of Canada

L'auteur a évalué les méthodes d'installation et la fiabilité des pompes à chaleur. Les appareils étudiés sont modèles commerciaux qui ont été installés par des entrepreneurs locaux dans des maisons construites dans la région d'Ottawa entre juin 1978 et mai 1982. Dix-huit installations ont été contrôlées en 1981-1982, et vingt-trois l'année suivante. Au cours de cette periode de deux ans, on a dû effectuer 0,54 correction par année-appareil.

Contract No. 0SX80-00062, prepared for National Research Council of Canada

The operation of heat pumps for residential space heating is described. The air-to-air heat pump is able to compete economically with electrical resistance heating systems. From a "prime" energy use point of view, it can raise the over-all efficiency of electrical heating from 28 to 42 per cent. If the seasonal performance factor could be improved, in this case by 35 per cent, the air-to-air heat pump would be more resource energy efficient than conventional oil and gas furnaces. Other heat pump systems, listed below, require further investigation to assess their potential for residential application: (i) ground source heat pump, (ii) solar-assisted heat pump, (iii) "ice-maker" heat pump. Important factors that need to be considered in the use of heat pumps are: (i) initial cost to the consumer, (ii) system reliability, (iii) load factor and time of peak demand on the electrical utility., L'auteur décrit l'utilisation des pompes à chaleur pour le chauffage des locaux résidentiels. La pompe à chaleur air-air est capable de concurrencer économiquement les systèmes de chauffage à résistance électrique. Du point de vue de l'utilisation "efficace" de l'énergie, les pompes à chaleur peuvent faire passer le rendement général du chauffage électrique de 28 à 42%. Si le facteur de l'efficacité saisonnière pouvait être amélioré, dans le cas présent de 35%, les pompes à chaleur air-air seraient plus efficaces en termes énergétiques que les systèmes conventionnels à l' huile et au gaz. Les autres sytèmes de pompes à chaleur, é numérés ci-dessous, méritent une étude plus poussée quant à leurs applications résidentielles possibles: i) pompe à chaleur utilisant l'énergie géothermique, ii) pompe à chaleur utilisant l'énergie solaire comme appoint, iii) pompe à chaleur pour la réfrigération. Les facteurs importants qui doivent être considérés dans l'utilisation de ces pompes à chaleur sont: i) le coût au départ pour le consommateur, ii) la fiabilité du système, iii) les facteurs de charge et les périodes de crête du réseau électrique.

Contract No. 11SQ.31040-6-0746-VII, prepared for National Research Council of Canada

Contract No. 079-007, Contract No. CS155-9-4404, prepared for National Research Council of Canada

The heat balance in a house depends on heat inputs and heat losses. By combining measured fuel consumptions for the furnace and hot water system with estimated heat gains from occupants, solar radiation, and electrical appliances, total useful space heat inputs were estimated as a function of outdoor temperature. Heat losses were also calculated as a function of outdoor temperature. From the resulting graphical relationships, estimates were made of heating system efficiencies. Changes in the fuel consumption- outdoor temperature relationship are given for several houses to which insulation was added. In two cases, addition of RSI 2 insulation to the attic and RSI 1.5 to basement walls (previously uninsulated) reduced fuel consumption by about 30%.

Contract No.: 1SX78-00103, prepared for National Research Council of Canada

DSS File No. 01SX.31155-2-4437, prepared for National Research Council of Canada

Submitted by Chromalox Canada, Inc., prepared for National Research Council of Canada, Division of Building Research, Contract Report: 0SX78-00058: D.S.S. File Number: 05SX.31155-8-4419

A mathematical model is developed to perform row-by-row simulation of finned-tube heat exchangers during cooling or cooling and dehumidification processes. Numerical solution of this model gives the air, water and tube surface temperature and the air specific humidity after each row of tubes along the coil depth., Sixth International Heat Transfer Conference: 1978-08, Toronto, ON, Canada

illus. 27 ref.; National audience

In a study of the energy consumption of apartment buildings, conducted under contract for the Division of Building Research, the possible effects of infiltration were given close scrutiny, since there seemed to be some major differences between these buildings and similar ones with other occupancies. This field study was aimed at establishing whether these differences existed in practice, and in particular if stack effect causes significant variations in the heating requirements of apartment units according to their location in tall buildings. Indications are that stack effect is suppressed in tall apartment buildings when supply and exhaust fans are running, and that the corresponding effect on heating consumption is weak or negligible depending on building height.

Utilization factors for internal heat gains have been derived from an hour-by-hour computer simulation using actual weather data for 11 Canadian locations. Curves are presented for conditions of constant room temperature and for allowable temperature rises of 2.75 and 5.5 degrees C. For houses with a ratio of internal gains to reference heat loss of less than 0.4, all internal gains can be utilized to offset thermal losses. In addition, the application of the utilization factor method is extended to calculation of heating energy reuirments of other buildings such as apartments, schools and offices.

The paper reviews ongoing Canadian activities related to utilization of solar energy for heating buildings. These include the formation of the Solar Energy Society of Canada, Inc.; a study on the feasibility of solar heating in Canada conducted in Canada by the University of Waterloo; and the initiation of six solar-heating demonstration projects under the Canadian Urban Demonstration Program. New activities reviewed are the $550,000 Federal funding program for encouraging solar heating in buildings; the forthcoming solar-heated Senior Citizen Home sponsored by the Province of Ontario; and the ongoing construction of privately-funded solar-heated homes. International activity on solar energy utilization is reviewed for comparison with the Canadian level of effort.

Based entirely on computer simulation, this study was carried out to determine the effect of the heat storage capacity of a building on its annual heating requirements. Specifically, the annual energy requirements were computed for a large office building and for a single-family house for three Canadian annual weather cycles and for a range of building interior and exterior wall thermal storage capacities. The study indicates that the thermal storage capacity of a building has a relatively small influence on the annual energy requirement for heating., Proceedings of the 2nd International CIB Symposium on Energy Conservation in the Built Environment : Session 2: 1979, Copenhagen, Denmark

This report contains a review of current solar-heating systems, a comparison of the economic competitiveness of solar-heating with conventional methods, and some guidance on the decisions that must be made in selecting a solar-heating system., Aussi disponible en français : Chauffage Solaire des Bâ timents au Canada

Contract No. 0SX78-00109, File No. 02SX.31155-8-4424, prepared for National Research Council of Canada

Information about the natural gas and electricity consumption, size, age, and style of construction was obtained for 1,478 houses in the city of Regina. Slope- intercept relationships between natural gas consumption and electricity consumption versus heating degree-days were determined for each house. Calculations were made to find the variation of energy consumption with several house characteristics. The variation in the slopes of the natural gas consumption versus heating degree-days was also studied. Variations with house size, and within several groups of nominally identical houses, were found.

Contract No.: OSR82-00026, prepared for National Research Council of Canada

illus. 3 ref. ; Traitements thermiques - communications; National audience

Contract No. 0SX800-00148, prepared for National Research Council of Canada

The need for a simple method for estimating the heating energy requirements of houses is widely recognized. An important aspect of such a method is the ability to estimate the amount of solar energy collected and used to offset heat losses. This note presents a simple method for calculating the heating energy requirements of direct-gain passive solar houses. The method is incorporated into a graphical procedure that can be easily used during the design process to optimize the amounts of south window area and thermal mass storage. It is applicable to the complete range of housing types, from high-mass direct-gain to low-mass sun- tempered. Sample calculations are included.

by Acres Consulting Services for the Division of Building Research, National Research Council of Canada, Contract No. 0SR77-00145, DSS File No. 20SR.31155-7-4427-2

Contract No. OSQ76-00149, prepared for National Research Council of Canada

Contract No.: 09SX.31155-0-4415, prepared for National Research Council of Canada

A report by W. L. Wardrop and Associates Ltd. for submission to the National Research Council, Division of Building Research, Contract No. OSR77-00143

The operation of heat pumps for residential space heating is described. The air-to-air heat pump is able to compete economically with electrical resistance heating systems. From a "prime" energy use point of view, it can raise the over-all efficiency of electrical heating from 28 to 42 per cent. If the seasonal performance factor could be improved, in this case by 35 per cent, the air-to-air heat pump would be more resource energy efficient than conventional oil and gas furnaces. Other heat pump systems, listed below, require further investigation to assess their potential for residential application: (i) ground source heat pump, (ii) solar-assisted heat pump, (iii) "ice-maker" heat pump. Important factors that need to be considered in the use of heat pumps are: (i) initial cost to the consumer, (ii) system reliability, (iii) load factor and time of peak demand on the electrical utility.

Also available in English: Research and Development on Extended Range Water Source Heat Pumps ; Report OS D77-09039

National audience; La méthode présentée permet de calculer les degrés-jours mensuels quelle que soit la température de base avec un écart-type d'erreur de l'ordre de 3 degrés-jours. Elle s'applique également aux degrés-jours de climatisation.

Seasonal Performance Factors between 1.5 and 2.4 were obtained when five water source and one ground source heat pump system were monitored for a designated period. These systems were located across Canada and, in some cases, all or a portion of the domestic hot water (DHW) requirements were also supplied by the heat pump systems. All systems operated satisfactorily without any major problems, providing substantial savings on energy bills for heating and DHW.

This article outlines a "modified" bin method for predicting heating energy requirements of residential air-source heat pumps. An illustrative example compares the proposed method with that recommended by ASHRAE. The results are then compared with the actual monitored heating energy requirement of a house identical to the one considered in the example. The "modified" bin method prediction is much closer to the observed consumption than the result of the standard ASHRAE method.