Case study of the upgrade of an existing office building for low energy consumption and low carbon emissions

Abstract

This case study evaluates the best energy efficiency measures of an existing two-story office building from the late 1960s located in Vancouver. Natural gas was used for heating and electricity was used for lighting, cooling and other needs. The building was simulated to match both metered data and bills. The energy model allowed identifying the parameters to reduce the energy consumption and mitigate the impact on CO2-eq emissions. On-site renewable energy supply was simulated. The return on investment (ROI) of the retrofit strategies (building envelope and renewable energy) was calculated to determine the profitability. From the parametric study, the insulation of the wall and roof, the airtightness and window replacement have the most impact on energy saving and allowed reducing 45% of the total annual energy consumed. These improvements can save more than 70 tons of CO2-eq per year from reducing the natural gas consumption. The return on investment of upgrading the building envelope was 7.7 years in Vancouver. Net zero energy building performance was possible with the addition of photovoltaic solar panel and solar heating to supply the total energy needs of the building, with an ROI of 11.6 years. If we changed the building location to Montreal, the same optimized building envelope reduces the energy consumption by 39%, and the energy saving increases to 56% when using the electric heating system usually already in place. Overall, building envelope upgrades are solutions to consider to improve energy saving in northern climate.

Energy Monitoring in a Heating and Cooling System in a Building Based on the Example of the Turówka Hotel

“…They include thermal insulation of the building envelope and replacement or use of window and door frames with a lower heat transfer coefficient as well as elimination of cold bridges. Energies 2020, 13,1968 4 of 20…”

“…The highest heat energy loss in a building is related to the ventilation system and heat exchange through dividing structures and windows and door frames. In a paper by Charles et al [13], the authors analyzed the improvement in energy performance of an existing two-story office building built in the late 1960s located in Vancouver, which involved replacing window frames, insulating external dividing structures (walls and roof), and installing renewable energy on an office building. The results showed that the improvement made on the building envelope allowed the reduction of 45% of the annual energy consumption.…”

“…Given the current waste production level in the EU, the generation of electricity from landfill biogas has great potential. F. Caresana et al [22] propose a number of solutions Energies 2020, 13,1968 5 of 20 to using biogas, including cogeneration systems. A study of a closed landfill in Mexico revealed that the use of energy from biogas obtained from a landfill is possible through monitoring the quantity and composition of the gases produced, while the generation of energy from municipal waste has higher potential compared to agricultural waste and forest residues [23].…”

“…Traditional systems do not perform their function at sub-zero temperatures and require additional protection against freezing. Tests have shown that not every recuperator provides adequate Energies 2020, 13,1968 6 of 20 ventilation of a building due to the ice periodically forming on the exchanger and causing flow to be reduced or stopped completely. The solution is to use additional preheaters or a system of dampers [35].…”

“…The average energy consumption slightly exceeds the average demand set for EU countries. However, many EU countries, such as Belgium, Estonia, Finland, Energies 2020, 13, 1968 3 of 20 Lithuania, or Slovakia, are characterized by higher consumption. For comparison purposes, it is also important to mention the climate in a given region, which directly translates into energy consumption, in particular heat energy required to heat rooms.…”