Balancing environmental impact, energy use and thermal comfort: Optimizing insulation levels for The Mobble with standard HVAC and personal comfort systems

Abstract

The energy crisis in the 1970s led to increasingly stricter building codes, resulting in the currently required nearly zero-energy buildings. Nonetheless, the energy saving potential of further increasing insulation packages decreases as a result of the inverse correlation of thermal transmittance with insulation thickness. Therefore, a balance is required between the potential energy savings and the material impact using Life Cycle Assessment (LCA). This balance is studied for a demonstration building called 'The Mobble'. For the LCA, the Ecoinvent database and impact assessment method ReCiPe H/A (2016) are used. For the potential energy savings dynamic energy simulations are run in Modelica/Dymola. To ensure equal comfort, thermal comfort is modelled using Human Thermal Module. An optimisation using the trade-off between material impact and operational energy by considering the optimal insulation thickness is executed on three levels: (1) building envelope (insulation, glazing type), (2) HVAC system efficiency (constant, demand based, personal comfort systems) and (3) electricity mix. This additionally enables to assess the robustness of imposing strict insulation requirements in e.g. building codes. The results show that even when extremely advanced demand based systems are adopted, the optimal insulation thickness ranges between 22 cm and 28 cm and is thus hardly affected, neither by user behaviour. However, the choice of energy mix does have a considerable impact on this optimal insulation thickness, and entails a shift in optimal insulation thickness from 20 cm -30 cm-10 cm -20 cm when a lower environmental impact for the electricity mix is considered (compared to the current Belgian electricity mix).

Life cycle analysis methodology for heating, ventilation and air conditioning ductwork in healthcare buildings

“…In these studies, air temperature, radiation across the duct surface, moisture and velocity have been identified as the most environmentally penalizing factors. 83,84 In developing countries, the purchasing power and the transport of materials are also aspects that need to be taken into account since there may be types of ductworks that are beyond those countries' reach.…”

“…In these studies, air temperature, radiation across the duct surface, moisture and velocity have been identified as the most environmentally penalizing factors. 83,84…”

Numerical Study on the Thermal Insulation of Smart Windows Embedded with Low Thermal Conductivity Materials to Improve the Energy Efficiency of Buildings

“…Heat transfer in the building envelopes accounts for 70-80% of the energy consumed. A proper design and materials of the building envelopes especially walls and windows play a vital role in controlling the heat transfer in and out the building while maintaining the interior thermal comfort [4]. The usage of highly thermal insulated materials as the building envelope is one of the sustainable strategies to reduce the overall heat transfer coefficient and concurrently reduce the heating and cooling load of the building.…”

Influencing of the Building Energy Policies upon the Efficiency of Energy Consumption: The Case of Courthouse Buildings in South Korea

“…Analyzing the primary building materials to enhance the non-residential G-SEED certified building systems was also performed previously [18]. In addition, studies about building insulation thickness mostly inspected the optimum insulation thickness, which concentrated on a certain insulation thickness material, before simulating them into a model [19][20][21] rather than analyzing the energy consumption of buildings based on actual historical data to assess the effectiveness of insulation thickness. On top of that, many current studies are focused on analyzing the energy consumption of residential buildings.…”