Influence of thermal zoning and electric radiator control on the energy flexibility potential of Norwegian detached houses

Abstract

Energy flexibility of buildings can be used to reduce energy use and costs, peak power, CO2eq- emissions or to increase self-consumption of on-site electricity generation. Thermal mass activation proved to have a large potential for energy flexible operation. The indoor temperature is then allowed to fluctuate between a minimum and maximum value. Many studies investigating thermal mass activation consider electric radiators. Nevertheless, these studies most often assume that radiators modulate their emitted power, while, in reality, they are typically operated using thermostat (on-off) control. Firstly, this article aims at comparing the energy flexibility potential of thermostat and P-controls for Norwegian detached houses using detailed dynamic simulations (here IDA ICE). It is evaluated whether the thermostat converges to a P-control for a large number of identical buildings. As the buildings are getting better insulated, the impact of internal heat gains (IHG) becomes increasingly important. Therefore, the influence of different IHG profiles has been evaluated in the context of energy flexibility. Secondly, most studies about energy flexibility consider a single indoor temperature. This is questionable in residential buildings where people may want different temperature zones. This is critical in Norway where many occupants want cold bedrooms (~16°C) during winter time and open bedroom windows for this purpose. This article answers to these questions for two different building insulation levels and two construction modes (heavy and lightweight).

Evaluation Method for the Hourly Average CO2eq. Intensity of the Electricity Mix and Its Application to the Demand Response of Residential Heating

“…For the sake of the simplicity, natural ventilation, which was usually applied in TEK87 buildings, is modeled as balanced mechanical ventilation with a heat recovery effectiveness η HR of 0%. This study considers the U-values of the building walls, but it should be noted that the building insulation level [15] as well as the thermal capacity of a building [60][61][62] influences the flexibility potential. The climate of Trondheim is also relevant for Norway in general.…”