Energy environmental matrix for buildings energy performance certificate evaluation

The residential building sector accounts for over 40 % of global energy demand and more than 35 % of CO₂ emissions. While energy performance certificates (EPC) are widely used to assess building efficiency, they lack clarity in communicating real energy and environmental impacts. This paper introduces the Energy Environmental Matrix (EEM), a novel three-dimensional method that simultaneously considers primary energy demand (EP), final-to-useful energy ratio, and equivalent emissions (ZrSO₂). A case study involving a single-family house located in southern Poland was used to evaluate 9 different heating system configurations. The results indicate that traditional fossil fuel systems, such as coal and oil boilers, exhibit high primary energy demand (70.9 and 69.8 kWh/m²year) and equivalent emissions (39.36 and 5.90 kg/year, respectively). In contrast, brine/water heat pumps combined with photovoltaic systems achieve the best performance, with primary energy demand reduced to 7.0 kWh/m²year and equivalent emissions as low as 0.62 kg/year – over 90 % lower than fossil fuel-based systems. The EEM matrix facilitates an intuitive and visual comparison of system efficiency and sustainability, providing a significant improvement over current EPC methods. This tool supports stakeholders in selecting low-emission technologies, aligning with ESG goals and climate action strategies.