Practical Implementation of Renewable Energy in Design of Buildings

Today’s increasing energy prices underscore the urgency and advantages of accelerating the development of cheaper and cleaner sources of energy. The natural gas crisis in Europe caused by Russia’s invasion of Ukraine has affected the energy market and fuel prices much more than expected [1]. The current situation requires a significant change in considering energy resource consumption. The household and business buildings and their construction sectors combined account for almost one third of total global final energy consumption and around 15% of direct CO₂ emissions among all energy-consuming sectors [2]. Buildings are responsible for around 40% of European Union energy consumption [3]; therefore, reducing energy consumption and the carbon footprint must be considered as soon as possible [4]. To reach these aims, many regulations, strategies, and directives have been deployed to lead the reduction of energy consumption by promoting energy efficiency actions [5]. Currently, energy systems planning and models are concentrated on analyzing the various renewable energy and energy efficiency measures implementations. The main aim is to comprehend the amount of main and primary energy resources that can be saved and their beneficial consequences on the environment [6]. Many studies have been conducted in different regions and energy sectors across the world. Among all of them, building raised the interest of many researchers [7]. Recent trends show that due to rapid urbanization around the world, above 70% of the total population will be living in cities by 2050. It is obvious that cities are featured by a large number of buildings which are undeniably responsible for a huge amount of energy consumption and carbon emissions [8]. Within European Union, Italy is the third energy-consuming country after Germany and France. Thus, different authors focus on the development of energy consumption models applied to the Italian building stock also in consideration of the high level of energy dependence of the country, especially natural gas which is used for heating and domestic hot water [9]. According to the most recent report published by the European Climate Foundation and the European Alliance to Save Energy (EU-ASE), electrifying and renovating Europe’s residential buildings can cut gas imports and generate massive benefits for the economy. The equivalent of 25% (or 1.45 EJ) of the EU’s current fossil gas imports from Russia (~5.5 EJ in 2020) can be saved by 2030 by renovating and electrifying Europe’s residential buildings. As a result, Europe could cut its annual spending on gas imports by €15 billion in 2030 and €43 billion in 2050 and therefore help increase Europe’s energy security [10]. As shown in Fig. 1.1, the Italian residential sector consumes the most natural gas during the last 15 years [11].

Today, energy crisis is one of the most crucial issues worldwide. The current situation requires a notable change in the consideration of energy resources and the way these resources are used. Among all energy-consuming sectors, the building and construction sectors jointly account for almost one third of the total global final energy consumption and approximately 15% of the direct CO₂ emissions [1]. Recent studies on energy have recognized that energy consumption in the building sector accounts for approximately 40% of the total energy use in Europe [2]. Hence, energy efficiency is the center of attention to improve the above situation. The European Union aims to achieve carbon neutrality by 2050, thus reaching an economy with zero greenhouse gas emissions. The EU submitted its long-term strategy to the United Nations Framework Convention on Climate Change (UNFCCC) in March 2020. The long-term low-greenhouse gas emission development strategy of the European Union and member states emphasizes energy efficiency improvement [3]. The European Council endorsed the 2030 Framework for Energy and Climate for the union based on four key union-level targets, two of which entail a reduction of at least 40% in economy-wide greenhouse gas (GHG) emissions and an indicative target of improvement in energy efficiency of at least 27%, to be reviewed by 2020 with an aim to increase this level to 30% [3]. To reach the 2030 and 2050 targets, a focus on existing buildings is very important because the rate of new building construction is relatively low, with an approximately 0.5–2% growth in the housing stock per year [4, 5].

Renewable energy resources play a crucial role in providing clean electricity and decarbonizing the environment. Among the different renewable energy resources, solar energy is one of the most abundant and cleanest sources available in the world. Of the 2799 GW of renewable energy produced in power plants in 2020, approximately 25% came from solar energy power plants [1]. The total installed capacity of solar energy (photovoltaic (PV) and concentrated solar power (CSP)) in the world was 716 GW in 2020, 99% of which was represented by solar PV systems [1]. The increasing number of installed PV plants across the world is notable, as shown in Fig. 3.1. It is also clear that the total amount of installed PV power plants increased by approximately 21% from 583 to 709 GW in 2020. This amount is expected to grow by 20% in 2022 [3]. Despite the challenges caused by the pandemic and numerous cost fluctuations in the PV market, the global race to cut carbon emissions continues and is predicted to pass 200 GW of PV power plant installation in the next year [4].

Heat can be transferred between the ground and built environments through ground source heat pumps consisting of primary and secondary circuits. The primary and secondary circuits include a ground heat exchanger and the built environment that can be heated or cooled, respectively (Fig. 4.1). Machines with electrical drives, namely, heat pumps, are applied between the mentioned circuits to raise the temperature from 12–15 °C to 45–50 °C to heat the superstructures [1].

Energy has always been a matter of debate around the world. Today, energy crisis is one of the most important global issues, particularly in Europe. The increasing price of energy sources caused by the Russian invasion of Ukraine and its economic consequences are inevitable [1]. The recent situation requires significant changes in energy resource consumption. Household and business buildings and their construction sectors, when combined, account for approximately one third of total global energy consumption and approximately 15% of direct CO₂ emissions among all energy consuming sectors [2]. Buildings are responsible for approximately 40% of the European Union’s energy consumption [3]; therefore, reducing energy consumption and carbon footprint levels must be considered as soon as possible [4]. To reach these aims, many regulations, strategies, and directives have been deployed to reduce energy consumption by promoting energy efficiency initiatives [5]. To date, energy system plans and models are generally implemented to analyze various renewable energy and energy efficiency measures. The main aim is to comprehend the amounts of primary energy resources that can be reduced and their environmental benefits [6]. Many studies have been conducted in different regions and energy sectors across the world. Among these studies, building initiatives have attracted the interest of many researchers [7]. Recent trends show that due to rapid urbanization around the world, more than 70% of the total population will live in cities by 2050. Obviously, cities feature many buildings that are undeniably responsible for high amounts of energy consumption and carbon emissions [8].

The continuous rise in global energy demand is heavily linked to the growth in population and improved economic and technological situations in most parts of the world. This demand is primarily met using coal, oil, and gas, or else known as “fossil fuel” resources [1]. The main issue of fossil fuels is that they produce carbon dioxide (CO₂) gases when they are burned. CO₂ is classified as a greenhouse gas (GHG); hence, increase in CO₂ production leads to increase in global warming [1].