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We conducted a re-analysis of data supplied by the New Buildings Institute and the US Green Buildings Council on measured energy use data from 100 LEED certified commercial and institutional buildings. These data were compared to the energy use of the general US commercial building stock. We also examined energy use by LEED certification level, and by energy-related credits achieved in the certification process. On average, LEED buildings used 18-39% less energy per floor area than their conventional counterparts. However, 28-35% of LEED buildings used more energy than their conventional counterparts. Further, the measured energy performance of LEED buildings had little correlation with certification level of the building, or the number of energy credits achieved by the building at design time. Therefore, at a societal level, green buildings can contribute substantial energy savings, but further work needs to be done to define green building rating schemes to ensure more consistent success at the individual building level. Note, these findings should be considered as preliminary, and the analyses should be repeated when longer data histories from a larger sample of green buildings are available.

The principal reason for introducing (and extending) daylight saving time (DST) was, and still is, projected energy savings, particularly for electric lighting. This paper presents a literature review concerning the effects of DST on energy use. Simple estimates suggest a reduction in national electricity use of around 0.5%, as a result of residential lighting reduction. Several studies have demonstrated effects of this size based on more complex simulations or on measured data. However, there are just as many studies that suggest no effect, and some studies suggest overall energy penalties, particularly if gasoline consumption is accounted for. There is general consensus that DST does contribute to an evening reduction in peak demand for electricity, though this may be offset by an increase in the morning. Nevertheless, the basic patterns of energy use, and the energy efficiency of buildings and equipment have changed since many of these studies were conducted. Therefore, we recommend that future energy policy decisions regarding changes to DST be preceded by high-quality research based on detailed analysis of prevailing energy use, and behaviours and systems that affect energy use. This would be timely, given the extension to DST underway in North America in 2007.

Behavioural models derived from on-going field studies can provide the basis for predicting personal action taken to adjust lighting levels, remedy direct glare, and save energy in response to physical conditions. Enabling these behavioural models in advanced lighting simulation programs, such as DAYSIM and the Lightswitch Wizard, allows for a more realistic estimate of lighting use under dynamic conditions. The current downside of these approaches is that the whole building energy impact of manual changes in blind settings and lighting use, including its effect on heating and cooling requirements, is not considered. A sub-hourly occupancy-based control model (SHOCC), which enables advanced behavioural models within whole building energy simulation, is presented. The considered behavioural models are the Lightswitch2002 algorithms for manual and automated light and blind control, while the investigated whole building energy simulation program is ESP-r. The enhanced functionality is demonstrated through annual energy simulations aiming at quantifying the total energy impact of manual control over lights and window blinds. Results show that building occupants that actively seek daylighting rather than systematically relying on artificial lighting can reduce overall primary energy expenditure by more than 40%, when compared to occupants who rely on constant artificial lighting. This underlines the importance of defining suitable reference cases for benchmarking the performance of automated lighting controls. Results also show that, depending on the proportion of buildings occupants that actively seek out daylighting, reduced lighting use through automated control may not always produce anticipated savings in primary energy for indoor climate control. In some cases, reduced lighting use is shown to even increase primary energy expenditure for indoor climate control, trimming down initial primary energy savings in lighting alone. This reveals the superiority of integrated design approaches over simpler daylighting guidelines or rules of thumb.

This paper reports on two experiments conducted in the same office laboratory. As part of a larger experiment, 58 participants worked for a day under one of two lighting designs. The first design used ceiling-recessed parabolic luminaires only; the second design employed the same parabolic ambient lighting, with the addition of an angle-arm task light. Participants had no control over the lighting until the afternoon, when they were offered dimming control over the ambient parabolic lighting; participants with task lighting were also permitted to move the arm location. During the day participants performed a variety of simulated office tasks, as well as completing a number of questionnaires on mood, satisfaction, and discomfort. There was no main effect of lighting design on questionnaire outcomes, however, task lighting was associated with performance improvements on some tasks. Interestingly, provision of a task light did not lower participants' preferred ambient light output. The second experiment, with 31 participants, followed up on this final point. Again, ambient lighting was provided by ceiling-recessed, parabolic luminaires, and participants were provided with a task light. For two task light types (angle-arm and luminous shade) at three different levels of output (0%, 50%, and 95%), participants used a dimmer to select their preferred level of ambient lighting. Increasing task lighting did reduce chosen ambient light output, but the reduction in lighting power was small, and only about the same as the power drawn by the task light. Results suggested that participants did not dim ambient lighting further because they preferred to maintain illumination on non-task surfaces, and to avoid extreme luminance ratios.

This is one of two papers that outlines the methodology used to develop, through computer simulation, skylight design tools for thermal and energy performance of atriums in cold climates. The methodology identified important design alternatives that included skylight and atrium physical variables, and a series of thermal and energy performance outputs that may serve as selection criteria for an energy-efficient design. New prediction models were developed to overcome some computer-simulation limitations, which included models to deal with airflow between an atrium and its adjacent spaces and temperature stratification within an atrium space. The developed airflow network model is a technique used to predict the mutual influence between the atrium and its surrounding spaces without requiring additional geometrical information on the surrounding spaces. The developed temperature stratification model is consistent with airflow network models and the zone concept used in building thermal-simulation programs since it takes into account radiation (overlooked in airflow network models) and convection heat transfer at the same time. This was done through treating fictitious surfaces that separate the thermal zones in a similar way as real surfaces. Fictitious surfaces were assigned a high emissivity, high solar transmittance, high thermal conductivity and convection film coefficient of 10 W / m 2 ° C . These values were found to yield reasonable solar radiation absorption, convection and radiation heat balances for the real surfaces irrespective of the number of the thermal zones. The developed models were integrated into a simulation computer program, and then validated against field measurements of a case study atrium. The predicted indoor temperatures were within ±2°C of the measured ones in both winter and summer days.

This paper presents an analysis of the impact of selected design alternatives on the thermal and energy performance of atriums based on the methodology outlined in the accompanying paper. Computer simulation programs were used to predict the impact of the selected design alternatives on the design performance outputs of atriums. Design alternatives focused on fenestration glazing types, fenestration surface area, skylight shape, atrium type, and interaction of the atrium with its adjacent spaces. Design performance outputs, evaluated with respect to a basecase design, included seasonal solar heat gain, cooling and heating peak loads and annual cooling, heating and total (heating plus cooling) energy. Design tools were developed to quantify the impact of the design alternatives on the performance outputs. The design tools were cast into two-dimensional linear relationships with the glazing U-value and SHGC as independent parameters. The results for the enclosed atriums showed that the annual cooling energy ratio increased at a rate of 1.196 per unit of SHGC ratio and decreased at a rate of 0.382 per unit of U-value ratio. However, the annual heating energy ratio increased at a rate of 1.954 per unit of U-value ratio and decreased at a rate of 1.081 per unit of SHGC ratio. Similar trends were also found for the three-sided and linear atriums. Pyramidal/pitched skylights increased the solar heat gain ratio by up to 25% in the heating season compared to flat skylights. The effect of the skylight shape on the annual cooling and heating energy may be positive or negative, depending on the glazing U-value and SHGC ratios and the atrium type. Atriums open to their adjacent spaces reduced the annual cooling energy ratio by up to 76% compared to closed atrium spaces. However, open atrium spaces increased the annual heating energy ratio by up to 19%.

This paper is one in a series of publications to present partial results of this project. Experimental data and computer simulation comparison of a set of wall specimens are presented together with a summary of the proposed procedure for the determination of the energy rating of insulated walls (WER)., 10th International Conference for Enhanced Building Operation: 26 October 2010, Kuwait

Based on the data collected from December 2006 to November 2008 and field investigations, the energy consumption and indoor environment quality of an energy efficient office building located in Montreal was analyzed, as a preliminary step of developing a high performance office building database. The results show that both climatic conditions and building occupant activities play significant roles in influencing the characteristics of building energy use. At the same time, energy saving measures along with reasonable operation can not only reduce building energy consumption but also greatly contribute to occupants' satisfaction and productivity. Moreover, effective measures to help occupants know about the advanced features of energy efficient buildings are still necessary in order to further reduce energy use and improve indoor environment quality. In addition, the monthly energy use intensity of this building is compared with an energy efficient office building, which was designed to be submitted for LEED (Leadership in Energy and Environmental Design) Gold certification, and the results indicate there is still great potential for energy conservation in this building., The 7th International Conference on Indoor Air Quality, Ventilation and Energy Conservation in Buildings (IAQVEC 2010): 15-18 August 2010, Syracuse, New York, USA

Peak demand for electricity in North America is expected to grow, challenging electrical utilities to supply this demand in a cost-effective, reliable manner. Therefore, there is growing interest in strategies to reduce peak demand by eliminating electricity use, or shifting it to non-peak times. This strategy is commonly called “demand response”. In households, common strategies are time-varying pricing, which charge more for energy use on peak, or direct load control, which allows utilities to curtail certain loads during high demand periods. We reviewed recent North American studies of these strategies. The data suggest that the most effective strategy is a critical peak price (CPP) program with enabling technology to automatically curtail loads on event days. There is little evidence that this causes substantial hardship for occupants, particularly if they have input into which loads are controlled and how, and have an override option. In such cases, a peak load reduction of at least 30% is a reasonable expectation. It might be possible to attain such load reductions without enabling technology by focusing on household types more likely to respond, and providing them with excellent support. A simple time-of-use (TOU) program can only expect to realise on-peak reductions of 5%.

L'étude sur la ventilation mixte de l'IRC-CNRC est d'autant plus importante que la ventilation et la climatisation représentent jusqu'à 50 % de la consommation énergétique d'une habitation et qu'elles ont un impact direct sur la santé et le confort des occupants. La ventilation naturelle a pour inconvénients ses échanges d'air frais excessifs ou insuffisants, lesquels entraînent irrémédiablement des déperditions d'énergie de chauffage ou de refroidissement. Plus facile à contrôler, la ventilation mécanique permet de récupérer la chaleur et de filtrer l'air, mais elle présente l'inconvénient de fonctionner à l'électricité et de contribuer ainsi aux émissions de gaz à effet de serre. Dans ce contexte, la ventilation mixte, qui associe les avantages de la ventilation mécanique et de la ventilation naturelle, apparaît comme une solution susceptible de réduire l'énergie utilisée pour ventiler les bâtiments., Also available in English: Use of vents and stacks for natural ventilation

The research is important because ventilation and air-conditioning can account for up to 50% of residential energy consumption, while having a direct impact on occupant health and comfort. Natural ventilation may result in too little or too much fresh air exchange, and may waste energy in heating or cooling a space. Mechanical ventilation is easily controlled and enables heat recovery and filtration but it consumes electrical energy and thereby promotes greenhouse gas emissions. Hybrid ventilation, combining the advantages of both natural and mechanical ventilation, may offer a way to reduce the energy used for building ventilation., Aussi disponible en français: L'utilisation d'évents et de conduits d'évacuation en ventilation naturelle

Aussi disponible en français: Les codes modèles nationaux traiteront de l'efficacité énergétique dans les bâtiments

A study was conducted in cubicle workstations occupied by individuals conducting their regular office duties. The workstations were lit by dimmable direct-indirect luminaires controlled via DALI protocol by occupancy sensors in each luminaire and personal controls located on the occupants' computer screens. The energy use and power demand attributable to the lighting controls were compared to those of a conventional lighting system previously in place. The occupants' opinion of the DALI system was also examined. Despite a low frequency-of-use, the personal controls were mentioned by 75% of the occupants as a feature they appreciated having. In contrast, only 30% of the occupants liked the occupancy sensors. Despite the fact that the DALI system had an installed lighting power density 50% higher than the conventional system, with both controls in operation it saved 32% in daily energy use. This shows that lighting power density does not uniquely define energy performance. Time-of-use, which is strongly linked to controls, is critically important., Lux Europa 2009, 11th European Lighting Conference: 09 September 2009, Istanbul, Turkey

We report the savings realized by the use of lighting controls across a college campus in southern Ontario, Canada. The campus had an extensive lighting system of addressable dimming ballasts, controlled and monitored centrally. Of the 2295 luminaires from which we recovered data, 87 were controlled by 62 photosensors; these were in rooms that also featured a manual control system (wall switch/dimmer/preset scenes) and occupancy sensor. The site was monitored from mid-April to mid-July, 2008. Substantial energy savings were realised by the control system, though savings varied greatly by control type, room type, and by day. Manual use of wall switches and switching by occupancy sensors contributed most to savings. Meaningful additional savings were contributed by dimming, either by a photosensor or use of preset scenes. We provide a detailed breakdown of the savings by control and room type. Note that in a large space occupant sensors/wall switches affected all luminaires, whereas photosensors affected only those luminaires close to windows or skylights., Lux Europa 2009, 11th European Lighting Conference: 9 September 2009, Istanbul, Turkey

This paper describes a parametric assessment of energy usage budgets for selected building envelope assemblies. The simulation study was conducted as part of a project to develop building envelope assemblies that are energy efficient and durable under extreme cold outdoor climates and indoor conditions typically found in these climes. Energy costs in northern Canada are high especially in the Arctic where communities are accessible only by air or boat or ice roads. Energy efficiency is therefore a primary objective here however this objective must be balanced with transportation and construction costs, which are also high. The objective of the simulation study was to compare the energy performance of proposed high performance wall assemblies with typical baseline wall assemblies. Four high performance walls were compared with two baseline walls, one a wall typical of low latitude regions, and the second a typical arctic wall assembly. Seven locations were selected for analysis, 2 representing western, 2 representing central, and 3 representing eastern arctic conditions. Three buildings were simulated, a fully detached home, a middle unit of a multiunit residence, and an end unit of a multiunit residence. A model for estimating the change in energy consumption with changes in wall thermal conductance was developed. Obviously the most highly insulated wall system exhibits the best performance with respect to space heating consumption. Recommending a wall type was outside the scope of this study but within the scope of the larger project. The objective of this work was to provide a method to easily determine change in space heating consumption due to a change in wall construction, which can then be used as the basis for a total life cycle assessment of the proposed walls., The Fourth International Building Physics Conference: Energy Efficiency and New Approaches: 15 June 2009, Istanbul, Turkey

The need to reduce energy use as part of a strategy to alleviate environmental stresses is widely accepted. Buildings are big end-users of energy; buildings account for 20-40% of the energy demands in developed nations, and the rate of new building construction in developing nations is accelerating. To reduce the impact that buildings have on the environment, the need for them to use as little energy as possible while still providing a satisfactory indoor environment is critical. The green building movement may be an effective catalyst for this, and various green building rating schemes are now in the marketplace worldwide. Certified 'green' commercial buildings exhibit higher real-estate values, presumably reflecting expectations for reduced operating costs, and improved organizational productivity through better indoor environments for employees. However, the higher market value cannot be maintained in the long run if these buildings do not deliver their expected benefits. The early generations of 'green' certified commercial buildings have now been occupied for several years, and it is time to explore whether these 'green' buildings are living up to expectations in objective terms. This paper reviews several of the post occupancy evaluations (POEs) that have been performed. A limited number of POEs are available in the public domain, making it difficult to draw solid conclusions. However, early trends suggest that green buildings on average seem to be delivering reduced energy use, however a large spread in performance is often observed meaning that individual buildings do not always perform as expected. Occupant satisfaction with some aspects of the indoor environment appears to have improved compared to conventional buildings, but there are areas where expected improvement trends are not realized. This paper provides some possible explanations for the observed performance, and describes a new, Canadian-led, research project that aims to explore these issues further., 3rd International Conference on Smart and Sustainable Built Environments: 15 June 2009, Delft, the Netherlands

This paper describes a parametric assessment of energy usage budgets for selected building envelope assemblies. The simulation study was conducted as part of a project to develop building envelope assemblies that are energy efficient and durable under extreme cold outdoor climates and indoor conditions typically found in these climes. Energy costs in northern Canada are high especially in the Arctic where communities are accessible only by air or boat or ice roads. Energy efficiency is therefore a primary objective here however this objective must be balanced with transportation and construction costs, which are also high. The objective of the simulation study was to compare the energy performance of proposed high performance wall assemblies with typical baseline wall assemblies. Four high performance walls were compared with two baseline walls, one a wall typical of low latitude regions, and the second a typical arctic wall assembly. Seven locations were selected for analysis, 2 representing western, 2 representing central, and 3 representing eastern arctic conditions. Three buildings were simulated, a fully detached home, a middle unit of a multiunit residence, and an end unit of a multiunit residence. A model for estimating the change in energy consumption with changes in wall thermal conductance was developed. Obviously the most highly insulated wall system exhibits the best performance with respect to space heating consumption. Recommending a wall type was outside the scope of this study but within the scope of the larger project. The objective of this work was to provide a method to easily determine change in space heating consumption due to a change in wall construction, which can then be used as the basis for a total life cycle assessment of the proposed walls., Fourth International Building Physics Conference: Energy Efficiency and New Approaches: 15 June 2009, Istanbul, Turkey

In this article we present research on the thermal effects of shading devices in cold-climate houses, which we hope will provide valuable supplemental information to the lighting designer. In Canada, the energy demand for residential heating and cooling accounts for 62% of the total energy of average homes. Although the overall cooling energy demand is much lower than that for heating, some highly-populated areas experience a peak demand for electricity on summer afternoons. Effective solar shading devices such as exterior movable insulating shutters and interior highly-reflective shades may reduce residential energy demand for heating and cooling and improve thermal conditions near windows.

This paper describes a prototype desiccant evaporative cooling system (DEC) and presents its performance in term of indoor humidity control and energy efficiency. Experimental and simulation results show that the desiccant evaporative cooling system can achieve better humidity control and acceptable comfort conditions. The simulation results show that the desiccant cooling system is especially well suited for areas of the country with a high latent load. However the study identified a series of improvement measures to undertake in order to improve the energy efficiency of the unit., 12th Canadian Conference on Building Science and Technology: 06 May 2009, Montréal, Québec

Hydrogen is seen as an energy carrier of the future and significant research on hydrogen generation, storage and utilization is accomplished around the world. However, an appropriate intermediate step before wide hydrogen introduction will be blending conventional fuels such as natural gas, oil or diesel with hydrogen and follow up combustion through conventional means. Due to changes in the combustion and flame characteristics of the system additional research is needed to access the limits and the impact of the fuel mix on the combustion systems performance. The hybrid system consists of a 5 kWel electrolyzer and a residential 15 kWth high efficiency gas fired furnace. The electrolyzer was integrated with the furnace gas supply and setup to replace 5–25% of the furnace natural gas flow with hydrogen. A mean for proper mixing of hydrogen with natural gas was provided and a control system for safe system operation was developed. Prior to the start of the field trial the hybrid system was investigated in laboratory environment. It was subjected to a variety of steady state and cycling conditions and a detailed performance and optimization analysis was performed with a range of hydrogen/natural gas mixtures. The optimized system was then installed at the Canadian Centre for Housing Technologies (CCHT) Experimental research house. The energy performance of the hybrid system was compared to the energy performance of an identical high efficiency furnace in the Control research house next door.

On utilise depuis plusieurs années les dispositifs de contrôle de l'admission de la lumière du jour afin d'éviter le réchauffement excessif des intérieurs résidentiels. Cependant, il n'existe que peu d'études qui quantifient de façon significative les avantages réels de ces dispositifs., Also available in English: Solar shading devices save energy in houses

Window shading devices have been used for many years to prevent overheating of houses. Few studies have been done, however, to quantify the benefits in a meaningful way., Aussi disponible en français: Des économies d'énergie grâce aux dispositifs pare-soleil pour fenêtres résidentielles

This article describes the characteristics and operation of a prototype DEC system and presents results of tests carried out on a system to assess its performance in term of humidity control and energy efficiency.

As one objective of the International Energy Agency's Energy Conservation in Buildings and Community Systems Programme Annex 42, detailed Canadian household electrical demand profiles were created using a bottom-up approach from available inputs, including a detailed appliance set, annual consumption targets and occupancy patterns. These profiles were created for use in the simulation of residential cogeneration devices to examine the issues of system performance, efficiency and emission reduction potential. This article describes the steps taken to generate these 5-min electrical consumption profiles for three target single-family detached households – low, medium and high consumers, a comparison of the generated output with measured data from Hydro Quebec, and a demonstration of the use of the new profiles in building performance simulations of residential cogeneration devices.

Aussi disponible en français: La CCCBPI ajoutera l'efficacité énergétique des maisons aux objectifs du Code national du bâtiment

Cet article présente les résultats d'expériences menées au Centre canadien des technologies résidentielles, ayant pour objet de comparer la performance de deux (2) types de stores ou toiles pour fenêtres résidentielles : à volet roulant pour extérieur et à enroulement automatique pour intérieur., Also available in English: Window shadings reduce residential cooling energy

This article presents results of experiments at the Canadian Centre for Housing Technology comparing the performance of two types of window shadings for houses: exterior rollshutters and interior blinds., Aussi disponible en français: Des pare-soleil pour réduire l'énergie de refroidissement de votre maison

Ce numéro traite des résultats d'un projet de recherche consacré aux effets de deux types de vitrage à haut rendement (gain solaire faible et gain solaire élevé) sur la consommation d'énergie des résidences.

This Update discusses the results of a research project that examined the impacts of two types of high-performance window glazing (low solar heat gain and high solar heat gain) on energy consumption in residential applications.

This paper provides an experimental evaluation of the efficiency of an ERV for a range of summer temperatures in Ottawa Canada, including humid summer days. The evaluation was achieved using the twin houses at the Canadian Centre for Housing Technology (CCHT), and their 'side-by-side testing' to measure the real impact of the installation of the ERV. Significant electrical energy savings and improved indoor humidity control were achieved., 5th Windsor Conference: Air Conditioning and the Low Carbon Cooling Challenge, July 27, 2008, Windsor, UK

69th Annual Convention of the Canadian Psychological Association: 12 June 2008, Halifax, N.S.

When applying computer simulation tools in practice uncertainties abound, for example in material properties and boundary conditions. To facilitate the quantification of the effects of uncertainties, the differential, factorial and Monte Carlo methods have been implemented within a simulation tool, ESP-r. These methods require multiple simulations to extract statistical measures of model uncertainty. An alternative approach is to embed uncertainty considerations within the simulation tool's algorithms. The principle advantages of this approach are that the uncertainty is quantified at all times and therefore requires only a single simulation. Coupled with this, it is possible to take control action based on the prevailing effects of uncertainties. This paper details the mathematical techniques required to integrate uncertainty considerations within the energy conservation equations when applied to the simulation of buildings. A comparison is made between the use of this novel approach and traditional mechanisms of assessing uncertainty.

This article describes NRC-IRC software programs which help provide users with the capabilities to calculate sophisticated light, materials emissions and acoustics impacts on indoor environments at the design stage. They also enable designers and manufacturers to create products achieving the higher level of performance sought by developers, owners and occupants. They also help facility managers operate interior spaces that maximize the comfort, productivity, health, and safety of occupants.

The prospect of installing energy efficiency measures in buildings leaves some people afraid that they will ?freeze in the dark?. Surveys of employers show that they are reluctant to make changes that they fear could adversely affect employee performance and satisfaction. Fortunately, present-day technology exists that can satisfy occupants and their employers and reach energy-efficiency targets also. This presentation, based on NRC-IRC field and laboratory research, will show how advanced controls and other technologies can add to occupant comfort and satisfaction, while also saving energy and reducing peak demand., Better Buildings 2007: 25 April 2007, Winnipeg, Manitoba

The question: 'How large an effect can changing the glazing system's solar heat gain characteristics have on the overall energy consumption of a house?' can be posed by energy analysts, homeowners and glazing specialists alike. In an effort to quantify such an effect, two sealed, low emissivity, insulating glazing systems (with different solar transmission properties) were evaluated in a side-by-side experiment involving twin-houses, comparing their respective effects on house heating energy consumption (i.e., natural gas for space heating and electricity for air distribution) in a cold climate. This research project was conducted at the Canadian Center for Housing Technology (CCHT) located on the National Research Council Campus in Ottawa. This facility consists of two R-2000 houses that are very nearly identical in every aspect, and are fully instrumented, 11th Canadian Building Science and Technology Conference: 22 March 2007, Banff, Alberta

When electricity demand has the potential to exceed supply, brownouts or blackouts may occur. Utilities may take steps to deliver additional power, or to reduce demand. The latter case may involve commercial buildings shedding load when prompted by the electrical utility. We reviewed the literature on the effect of steady changes (ramps) in temperature and illuminance from electric light on occupants. On balance, our findings suggest that load shedding typical of current suggested practice is a reasonable response to peak power emergencies., The 2006 ACEEE Summer Study on Energy Efficiency in Buildings: 13 August 2006, Pacific Grove, California

The first fuel cell (FC) in a residential application in Canada was tested at the Canadian Centre for Housing Technology (CCHT). A 5kW second-generation solid oxide fuel cell manufactured in Canada was run for 1587 hours during the late winter and spring of 2005. Modifications to one of the CCHT houses allowed heat from the FC to be used for space heat and hot water, and electricity to be sent to and from the grid. This project demonstrated the performance of a residential FC combined heat and power (CHP) system, and examined residential CHP integration issues such as thermal storage, grid connection, and optimal FC size. Data collection included the FC's natural gas use and outputs of electricity and heat, electricity to and from the grid, heat to space heat and hot water, and supplementary heat (natural gas) required. The efficiency with which the FC generated electricity (DC & AC) and heat were measured, and found to agree with the manufacturer's specifications. The average measured efficiencies of the fuel cell, in terms of the lower heating value (LHV) of natural gas, are: DC electrical: 46.6%, AC electrical: 24.7%, and thermal: 27.6%. Combining AC and thermal yields an overall efficiency of 52.3%., ACEEE Summer Study on Energy Efficiency in Buildings 2006, American Council for an Energy Efficient Economy: 13 August 2006, Pacific, Grove, CA., U.S.A.

Aussi disponible en français: Effets prouvés de l'éclairage d'appoint sur les employés de bureau et sur la consommation d'énergie

Behavioural models derived from on-going field studies can provide the basis for predicting personal action taken to adjust lighting levels or remedy direct glare in response to physical conditions. SHOCC, a sub-hourly occupancy-based control model, provides building energy simulation programs, such as ESP-r, access to advanced behavioural models, such as the Lightswitch2002 algorithms intended manual and automated lighting systems. The effectiveness of the approach is demonstrated through annual energy simulations aiming at quantifying the total energy impact of manual control over lights and window blinds. Results show that by enabling manual control, as opposed to using predefined lighting profiles for core zones, total primary energy expenditure is reduced by as much as 62%. This underlines the importance of defining suitable reference cases for benchmarking the performance of automated lighting controls. Results also show that reduced lighting use through automated control may not always produce anticipated savings in primary energy for indoor climate control; in some cases, reduced lighting use is shown to even increase primary energy expenditure for indoor climate control, trimming down initial primary energysavings in lighting alone. This supports the use of integrated approaches rather than simple guidelines in designing lighting solutions., Buildings Simulation 2005, August 15, 2005, Montreal, Quebec, Canada

The purpose of this project is to establish inter-dependence of lighting on the overall energy usage in housing. Based on the inter-dependence effects, the overall impacts of compact fluorescent lamps (CFL) in housing applications can be evaluated., Ce projet a pour but de déterminer l'interdépendance entre éclairage et consommation d'énergie primaire dans les logements. Il est possible d'évaluer l'incidence globale des lampes fluorescentes compactes (LFC) dans les applications liées au logement en se fondant sur les effets de l'interdépendance.

This report presents the results of several window shading experiments conducted at the Canadian Centre for Housing Technology (CCHT) research centre located in Ottawa, Canada, to identify a testing procedure for window shading products. The results provided an overview of the order of magnitude of the energy effects that can be expected from shading devices in a residential dwelling in Ontario in the summer and winter, and formed the basis for recommendations for an experimental procedure to be used in future research projects involving the testing of shading devices at CCHT.

This paper suggests a method how to predict electric lighting energy savings for photocell controls in daylit spaces taking manual blind control into account. The method predicts lower but supposedly more 'realistic' lighting energy savings than conventional simulation approaches. On the other hand, predicted savings are larger than those predicted by ASHRAE 90.1 power adjustment factors. The method is demonstrated in a hypothetical open plan office in Calgary, Canada. A comparative simulation study is presented using DOE.2 and the RADIANCE-based daylighting analysis tool DAYSIM. Simulation results were found to differ substantially between DOE2 and DAYSIM even in the absence of venetian blinds. These discrepancies were attributed to the underlying simulation algorithms and sky models. Despite these differences, both simulation programs yielded energy savings more than twice the static 10% allowed for by ASHRAE 90.1 power adjustment factors for on/off control., The ESIM 2004 Conference: 10 June 2004, Vancouver

This paper provides a background review of models predicting occupancy, occupancy-sensing control and manual environmental control, and outlines their current addition to whole building energy simulation, in particular ESP-r. It deals with how occupancy-related input data models are defined and used in whole-building energy simulation., The CIB Conference 2004: 02 May 2004, Toronto, Ontario

Daylighting is believed to reduce lighting energy needs for atrium ground floors and adjacent spaces. This study investigated this hypothesis by monitoring the daylight contribution and electric lighting consumption of two atrium buildings. One was equipped with a photocontrolled continuous dimming lighting system. The other was equipped with a photocontrolled automatic on/off lighting system. The daylighting performance was evaluated based on the daylight contribution to the indoor illuminance and the amount of electrical lighting displaced by daylighting via the daylight-linked lighting control systems.

This experiment was conducted in a mock-up office space in a laboratory. 118 participants worked for a single day under one of four lighting designs. They had no control over the lighting until the last half of the afternoon, when all participants were offered some form of individual dimming lighting control. During this working day they completed a variety of simulated office tasks (not analysed in this report, but to be reported later), as well as completing a number of questionnaires. The experiment was designed to address several research questions with direct relevance to office lighting practice. We looked at preferences for particular lighting designs, particularly designs that provide higher levels of vertical illuminance. We were also interested in whether local/task lighting sources reduced the demand for ambient lighting. We also examined whether providing individual dimming control over luminaires was beneficial., Cette expérience a été menée sur un modèle en vraie grandeur de surface de bureaux dans un laboratoire. Cent dix-huit (118) participants ont travaillé pendant une seule journée sous un de quatre éclairages différents. Ils n'avaient aucun moyen de commander l'éclairage jusqu'à la seconde moitié de l'après-midi, lorsque tous les participants se sont vu offrir une forme quelconque de commande de l'intensité de l'éclairage. Au cours de la journée de travail, les participants ont exécuté diverses tâches de bureau simulées (non analysées dans le présent rapport, mais qui doivent faire l'objet d'une communication ultérieure), en plus de remplir un certain nombre de questionnaires. L'expérience visait à aborder plusieurs questions de recherche directement pertinentes à la pratique en matière d'éclairage des locaux à bureaux. On a jeté un coup d'oeil aux préférences pour des modèles d'éclairage particuliers, surtout ceux qui offrent des niveaux plus élevés d'éclairement lumineux vertical. On était également intéressé à savoir si les sources d'éclairage local ou de tâche réduisaient la demande pour de l'éclairage ambiant. On a aussi examiné la question de savoir s'il était avantageux de permettre à chaque personne de commander l'intensité des appareils d'éclairage.

The COPE (cost-effective open plan environments) project investigates the effect of open-plan office design on the indoor environment and on the occupant satisfaction with that environment. COPE is sponsored by a consortium of North American public and private-sector organizations and relies on field, laboratory and simulation studies to address designaspects like acoustics, lighting quality, indoor air quality, operating costs and energy efficiency. This paper describes the influence of various design variables on the daylight availability and electric lighting requirements in open plan office spaces using the RADIANCE-based annual daylight simulation method DAYSIM. To make simulation results more reliable a manual and an automated blind control strategy have been considered. Five climatic centers which represent the ambient daylight conditions of 186 North American Metropolitan Areas have been identified. For these five climatic centers over 1000 officesettings have been investigated which feature varying external shading situations, glazing types, facade orientations ceiling designs and partition arrangements. The daylight performance of the offices was expressed in terms of their daylight autonomy distributions and energy savings for an ideally dimmed lighting system. The simulation results reveal, that the daylight availability in peripheral offices allowsfor electric lighting energy savings between 25% and 60% for an ideally commissioned, dimmed lighting system depending on the underlying blind control strategy. 2 nd row offices receive considerably less daylight even though a reduced partition height and increased ceiling reflectances can double electric lighting energy savings up to 40%., Conference Proceedings of the 2002 Summer Study of the American Commission for an Energy Efficient Environment (ACE): 18 August 2002, Pacific Grove, CA., U.S.A.

This paper presents the results of a pilot study to quantify the effect of daylight-linked lighting control systems on office building electrical lighting consumption. The study investigated the impact of various configurations of manually-operated venetian blinds on the performance of a commercial photo-controlled continuous dimming lighting control system. It was based on monitoring two side-by-side occupied offices over a one-year period to assess electric energy consumption and the space illumination as a function of blind slat angle and retraction area., 5th European Conference on Energy-Efficient Lighting - Right Light 5: 29 May 2002, Nice, France

The belief that individual control leads to beneficial behavioural outcomes underlies many recommendations to install individual controls for workplace lighting, temperature, and ventilation in workplaces. The present experiment compared the work performance and satisfaction of 47 office workers who were given choices concerning workplace lighting (CS) with age- and sex-matched partners (PP) who were given no choices but worked under identical lighting. Preferred luminous conditions were recorded for both groups. Satisfaction with lighting and the work environment were high for both groups, and the majority of participants chose lighting conditions consistent with current codes and standards for lighting, including energy use. CS participants had greater perceived control than PP participants, but there were no differences in satisfaction, mood, performance or health. PP participants' lighting choices, recorded at the end of the day-long session, created less VDT glare than CS choices. Although there was no short-term benefit of perceived control over lighting, it appears that experience with workplace conditions could lead to the ability to reduce unpleasant conditions if choices were available., Also presented at American Psychological Association 106th Annual Convention, San Francisco, August 1998.