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The distribution and delivery of fuels to the built environment is a mega-scale form of seasonal energy storage in the United States, delivering greater than 600 GW of energy during the winter, often in the form of heating, and with storage built up over periods of 6-8 months. Combined with Canada, this distribution system serves 85 million homes and businesses with a network spanning 5.4 million km. With increasing efforts to reduce the impact of buildings on the environment, the greater than 1,000 Mt CO2e/year emitted from this fuel consumption must be mitigated. In addition to energy efficiency and conservation, which remain the pillars of any climate mitigation scheme, one pathway to reduce CO2e emissions from buildi ngs is displacing delivered fossil fuels (e.g. natural gas) with low or zero carbon fuels, which can include methane-based fuels and hydrogen, generated from renewable energies/feedstocks or employing integrated carbon capture. Seeking to scale-up the generation and distribution of these low or zero carbon fuels in many regions throughout the U.S. and Canada, utilities are demonstrating the injection, blending, and delivery of these fuels. Of particular note are the hydrogen-focused demonstrations, which seek to quantify the risks and benefits of distributing hydrogen using legacy and purpose-built infrastructure, and its impacts on the downstream homes and businesses, with activity in numerous large metropolitan areas and in cold and hot climate zones alike. This paper provides an overview of these North American utility projects, which displace delivered fossil fuels with low or zero carbon fuels, from the end user perspective and with a focus on the hydrogen-based fuels, both blended and 100%. The authors compare and contrast these projects with similar projects abroad, where in the U.K., Germany, and Japan, for instance, significant fractions of homes and businesses already enjoy access to these non-fossil fuels. Finally, using the historical transition from manufactured gases to widespread distribution of natural gas, a ~30 year transition that occurred from the 1920s to the 1950s, the authors draw comparisons between this significant historical energy transition to the modern context, considering safety implications, regionality, impacts on HVAC equipment, and the role of codes and standards. [ABSTRACT FROM AUTHOR]

The occupant response to thermal discomforts plays a significant role in uncertainties associated with modeling and implementing building energy performance measures. In particular, for managers of small commercial building portfolios, a better understanding of the occupants' interactions with the HVAC system is necessary for managing these uncertainties and reducing discrepancies between predicted and actual energy use. In Canada, these buildings are currently underserved by energy conservation and thermal analysis tools because of their dispersion and lower payback potential. Smart thermostats, along with their centralized data collection platform, provide an efficient and low-cost solution to collect massive amounts of data from a portfolio of these buildings that can be used to improve the understanding of the occupants' behaviours and preferred thermal conditions. This paper presents the results of a longitudinal study based on the smart thermostat data from a portfolio of more than 240 small commercial buildings located in Ontario, Canada. We analysed the occupantthermostat interactions, as well as the HVAC setpoints adjusted by the portfolio manager, to answer two main questions: 1) what contextual factors are associated with the initializing of overrides in the portfolio of small commercial buildings, and 2) how do the thermal conditions managed by HVAC schedules (that are based on seasonality and occupants' feedback) and occupant overrides reflect industry-standard criteria; specifically PMV? The results can help the portfolio managers to better understand the users' interactions with the HVAC system under various circumstances and create efficient energy conservation programs while meeting the occupants' thermal preferences and organizational productivity. [ABSTRACT FROM AUTHOR]

In Canada, builders and energy advisors use HOT2000 for simulation of new housing and retrofits for various labelling, energy rating and incentive programs as well as code compliance. HOT2000 is a monthly building energy simulation tool, specifically made for low-rise residential buildings. It calculates monthly loads from a combination of first principles, and various simple mathematical models developed from hourly simulation tools. As a consequence of the methodology, many state-of-the-art Energy Conservation Measures (ECM) can not be simulated accurately in HOT2000. A Housing Technology Assessment Platform (HTAP) software was previously developed, using HOT2000 as the simulation engine. HOT2000 was chosen as the simulation engine, because of its wide adoption and acceptance by builders and professionals in Canada. HTAP can run parametric runs, and provide energy demand and costing for a variety of ECMs. However many ECMs require hourly simulations to provide accurate energy demand estimates. In order to be able to evaluate these ECMs in HTAP, a methodology has been developed to estimate hourly heating, cooling, domestic hot water, and plug load profiles using monthly loads, and hourly climate data. This paper presents the approach and its limitations, as well as some validation results. [ABSTRACT FROM AUTHOR]

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 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. [ABSTRACT FROM AUTHOR]