Peak Power Demand in Apartment Buildings: Insights from Smart Meter Data and Building Characteristics

Accurately estimating peak demand in apartment buildings is essential for properly sizing electrical connections and distribution boards, yet current guidelines in Finland often lack precision, especially when accounting for modern appliances and building technologies. This study combines technical data from 164 apartment buildings with hourly electricity consumption data from 2015 to 2021 to assess peak demand behavior across three levels: aggregated apartment loads, common-area loads, and total building consumption. Results are presented as area-based values (W/m<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>) to support early-phase engineering estimates. Key findings include significantly higher peak demands in buildings with apartment saunas and heat pump systems, as well as clear patterns in peak timing—most frequently occurring in winter months and during weekends. This study provides updated benchmarks and practical tools for electrical designers, updating and refining outdated estimation practices which are still based on guidelines from the 1980s. The results highlight the urgent need for modernized, data-driven methods for peak demand estimation, and call for further research on the influence of outdoor temperature, building structures, ventilation systems, equipment levels, occupant behavior, and emerging loads such as electric vehicle charging.