M. M. Armstrong

Synthetically derived profiles for representing occupant-driven electric loads in Canadian housing

As one objective of the International Energy Agencys 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 Québec, and a demonstration of the use of the new profiles in building performance simulations of residential cogeneration devices.

Condensation risk assessment on box windows: the effect of the window-wall interface

Windows generally have the lowest temperature index in current building types, and will consequently be the primary location for interior surface condensation. Surface temperatures can easily be calculated using thermal finite-element models, but these generally omit the effect of convection in the windows and the window–wall interface. Hence, there is a need to determine if specific interface details provide potential for condensation on the window components in which air leakage paths may be prominent. The article reports on a laboratory evaluation of condensation risk assessment in a hotbox with varying pressure differences and the introduction of deficiencies. It was concluded that the effect of the type of insulation in the window–wall interface was very low for isobaric boundary conditions, whereas it has a significant effect when pressure differences are applied.

Intelligent management of baseboard heaters to level peak demand

This paper presents results from an evaluation of a demand response (DR) strategy applied to residential electric baseboard heating loads. The underlying principle is based on storing electricity as thermal energy in the building envelope and household contents before the peak period and then discharging that stored energy to maintain conditions for thermal comfort during the peak period. Five different variations of the strategy were tested at the twin houses of Canadian Centre for Housing Technology (CCHT) for a four weeks period in the winter of 2015 using a side-by-side comparative assessment. The tests showed that a load shift up to 4 kW for the first 30 minutes and a total shift up to 5.7 kWh during the 2-hour period was possible, depending on the outdoor temperature. The approach holds significant potential for shifting peaks loads in locations where electricity is a major source of energy for space heating.