Subtask B: Design Process Tools
Optimization of Net-Zero Energy Solar Communities: Effect of Uncertainty Due to Occupant Factors
August 2011 - PDF 0.38MB
By: Scott Bucking, Andreas Athienitis, Radu Zmeureanu
This paper applies an energy optimization methodology to evaluate the impact of occupant factors on the net-energy consumption or generation of a community of net-zero energy or near net-zero energy homes located in Montreal, Quebec. The building simulation software EnergyPlus was used for energy simulations and Canadian national statistics were used to model occupant behaviour. Results showed that diversifying building designs can decrease the impact of variability of occupant behaviour and reduce peak loads.
Strategies for Reducing Peak Demand in Net-Zero Energy Solar Homes
August 2011 - PDF 0.62MB
By: José A. Candanedo and Andreas K. Athienitis
This paper investigates strategies to reduce peak loads in net-zero energy solar homes through the coordination of different design and operation strategies. The concept of net-zero energy homes, roughly defined as grid-tied houses that supply their energy needs with renewable energy sources over a period of interest, has gained in popularity in recent year. In spite of the clear advantages of this design approach, it is necessary to address the issue of peak loads and their impact on utility grids. Even if the net-zero energy goal is achieved during the period of assessment (e.g., one year), significant imbalances may be observed at smaller time scales. For instance, in northern latitudes, the generation of PV panels typically exceeds the energy use of the house during the summer months, while in winter the energy use of the house is larger than the generation of the PV system. Fluctuations of the ratio generation/use are also registered during the daily cycle. If a net zero energy house draws energy from the utility grid during peak periods, its impact on the grid will be similar to that of a conventional home, with the subsequent need for increased generation and transmission capacity.
Energy Performance, Comfort and Lessons Learned From a Near Net-Zero Energy Solar House
June 2011 - PDF 1.63MB
By: Matt Doiron, P.Eng., William O’Brien, Andreas Athienitis, Ph.D., P.Eng.
This paper examines the performance of a Canadian near net-zero energy solar house known as ÉcoTerra located near Montreal. The total energy consumption and energy end-use breakdown are presented and several findings from the energy analysis are discussed such as the importance of occupant behavior, occupant comfort and the improvements that could lead to achieving full net-zero energy performance . It was demonstrated that large reductions in energy consumption can be achieved with little effect on comfort. Occupants affect the loads significantly and need to be educated and given specific feedback about their energy use patterns in order to help them adjust their behavior for energy efficiency. Although already far below the typical home in energy consumption (about 90%), this paper shows how ÉcoTerra could consume even less energy and how similar houses could be designed or upgraded to achieve net zero energy.
Applying A Design Methodology for a Net Zero Energy House to Evaluate Design Processes and Tools
Eurosun 2010 Paper
March 2010 - PDF 0.05MB
By: W. O’Brien, et. al.
EcoTerra is a house near Montreal that combines passive solar features (large windows and integrated thermal mass) and active solar features (a BIPV/T roof and thermal storage system) to achieve near net-zero energy (NZE) [1]. This paper presents and applies a methodology for redesigning the house to achieve net-zero energy. The objectives are: 1) to demonstrate the use of tools of varying degrees of model resolution and 2) address any weaknesses and new useful features in existing tools.
Design Optimisation Methodologies for a Near Net Zero Energy Demonstration Home
Eurosun 2010 Paper
March 2010 - PDF 0.21MB
By: S. Bucking et. al.
This paper applies an energy optimization methodology to identify improvements to an existing near net-zero energy house located south of Montreal, Canada. As many of the design performance parameters are strongly coupled, a hybrid evolutionary algorithm was used to ensure full solution space exploration, and harmonized parameter variation. This paper presents a set of ‘lessons learned’ to be applied to the design of future net-zero energy homes.
Design, Optimization, and Modeling Issues of Net-Zero Energy Solar Buildings
Eurosun 2010 Paper
March 2010 - PDF 0.21MB
By: R. Klein et. al.
The design of net-zero energy solar buildings (NZESBs) presents a challenge because there is no established design strategy to systematically reach this goal and many of the available tools have limited applicability for such advanced buildings. This paper reviews current design practice and tools for designing NZESBs through a literature review and a survey. It also summarizes the results of some redesign and optimization case studies of existing NZESBs that Subtask B of the IEA SHC Task 40/ECBCS Annex 52 is performing. The outcome of this study identifies effective strategies for the use of design and optimization tools in establishing near optimal NZESB designs.
Solar 2002: A Belgian Pilot Project for Zero Energy Buildings
Eurosun 2010 Paper
March 2010 - PDF 0.37MB
This paper describes the “Solar 2002” building in Berlaar (Belgium) that was constructed by the Flemish non-profit organization Mondo vzw. The aim of this retrofit of an existing single family dwelling was the creation of an example project, demonstrating the potential of solar energy for the energy needs of buildings in a temperate, rather cloudy climate. This has led to a “Net-Zero Energy” building, that finally supplies more energy to the grid, then it consumes on an annual basis. This paper focuses on the energy-aspect for the building in use. Technical details of the building and the employed renewable energy technologies are given.