**1. Introduction**

*1.1. Background*

The EU has defined a target for reducing GHG emissions by at least 40% by 2030 compared to 1990 levels [1]. Their long-term goal is defined as "no GHG emissions" by 2050 [2]. Increased energy efficiency in buildings is defined as an important tool for both the short term and long term [3]. One of the "key actions" in the Action Plan related to the 2030 framework is a "renovation wave" of the existing building stock [2].

Within the "renovation wave", the European Commission recommends paying particular attention to energy-reducing refurbishment in types of buildings that support education and public health, such as schools and hospitals [2]. In swimming facilities, which support education and public health, the potential for energy reduction is considerable [4] and the literature associates these facilities with high specific energy use [5] and a large dispersion in energy use. The specific energy use ranges from 400 kWh/(m2·a) to almost 1600 kWh/(m2·a) [6–9]. This can be partially explained by the variations in age,

**Citation:** Smedegård, O.Ø.; Jonsson, T.; Aas, B.; Stene, J.; Georges, L.; Carlucci, S. The Implementation of Multiple Linear Regression for Swimming Pool Facilities: Case Study at Jøa, Norway. *Energies* **2021**, *14*, 4825. https://doi.org/10.3390/en14164825

Academic Editor: Marcin Kami ´nski

Received: 28 June 2021 Accepted: 4 August 2021 Published: 7 August 2021

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technology and the different maintenance routines [7], but the numbers also represent a large energy saving potential [7]. Regarding the building stock of swimming facilities in Norway [6], the overall excessive energy use is estimated to be 28%. This provides a considerable incentive for improvement initiatives.
