**1. Introduction**

The subject of the article is the issue of WE production, which is an important source of RE in the world. Undoubtedly, the topic raised is relevant to the energy transition currently taking place in most of the world's economies [1–3]. The main objective of the energy transition is to move from the dominant role of fossil/nuclear fuels to the consideration of diverse RE sources, where WE, if the physical conditions are right, can represent a significant share of the RE portfolio [4–6]. Due to the systematic growth of global energy demand, the rational use of energy from renewable sources is one of the most important elements of sustainable development, bringing tangible effects for humanity as well as energy and ecology [7–10].

It should be emphasized that the production of RE and the implementation of energy transition has been possible for two decades at least. It turns out that it was only the occurrence of appropriate institutional, economic, and social changes in economies that allowed the real energy transformation of entire economies to begin, including state structures,

**Citation:** Aydin, O.; Igli ´nski, B.; Krukowski, K.; Siemi ´nski, M. Analyzing Wind Energy Potential Using Efficient Global Optimization: A Case Study for the City Gda ´nsk in Poland. *Energies* **2022**, *15*, 3159. https://doi.org/10.3390/en15093159

Academic Editors: Ricardo J. Bessa and Davide Astolfi

Received: 16 February 2022 Accepted: 21 April 2022 Published: 26 April 2022

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**Copyright:** © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

local governments, businesses, and citizens [11–16]. Undoubtedly, most of the significant changes are due to the globalization processes that have been developing systematically for nearly 30 years. These processes have resulted in a significant increase in the interdependence between all markets [17–20]. This has contributed to a significant increase in the socio-economic level of countries [21–24]. Global economies are experiencing strong growth, which is being attributed to the increase in investment and the level of innovation [25–30]. In addition, we should notice the increase in the level of wealth of society, the emergence of new patterns of consumption, and changes in the labour market [31–39]. All this has contributed to the fact that both the production of RE from the national level to the level of the individual consumer and other activities related to the energy transition have found ground for implementation. In the case of the European Union (EU) member states, including Poland, the processes of energy transformation are intimately linked to the achievement of the Sustainable Development Goals [40–43]. It should be noted that many efforts also indicate that the effective implementation of energy transition processes requires bottom-up involvement and consideration of energy justice [44].

Significant development of RE in Poland took place at the beginning of the second decade of the 21st century when the process of implementing the third energy package and the implementation of the ambitious goals of the EU's climate policy started to be in charge under the commitments' so-called "20-20-20 in 2020", i.e., increasing energy efficiency by controlling energy consumption more, increasing the share of RE, and reducing carbon dioxide emissions [44]. RE sources are undoubtedly seen by European decision makers as a solution to reduce emissions [4]. RE sources are an alternative to primary and nonrenewable hydrocarbon fuels. Although RE is characterized by the cyclical replenishment of resources in natural processes, the level of consumption of this type of energy as a primary energy source is still low [5,6]. As shown in Table 1, the capacity of renewable sources has been increasing since 2010 and showed a significant increase in 2020. However, the capacity is not at the desired level to be able to use RE as a primary energy source.


**Table 1.** Installed capacity of RE sources [45].

Total global wind capacity is currently up to 743 GW, helping the world avoid over 1.1 billion tons of CO2 per year equivalent to the annual CO2 emissions in South America. However, WE sources with the capacity of 180 GW should be activated each year in the world to avoid the worst effects of climate change. This means that industry and policymakers must act quickly to accelerate the switch from traditional energy sources to RE sources [46,47].

In spite of the termination of China's feed-in tariffs (FiT) and the planned phase-out of the United States' full-rate Production Tax Credit (PTC), the world's two largest economies increased their combined market share by 15 percent to 76 percent [46].

A record for onshore installations was also achieved in the Asia Pacific, North America, and Latin America regions in the calendar year 2020. According to the International Energy Agency, in these three regions a total of 74 GW of new onshore wind power was installed. This represents a 76 percent increase in capacity over the previous year. There was just a 0.6 percent year-over-year (YoY) rise in new onshore wind installations in Europe last year, which was due to the slow recovery of onshore wind installations in Germany. There were

8.2 GW onshore installations in Africa and the Middle East last year, which is almost the same as in 2019 [46].

The main objective of this paper is to propose an approach to the problem of WE generation that will ensure the highest efficiency of the energy generation process and the economic viability of this process. In order to achieve the objective, the authors developed the following added values: an overview in terms of development of WE in Poland and Pomerania Voivodeship, which is the area in Poland with significant potential when it comes to WE, was carried out; a novel approach was proposed for fitting a statistical distribution to WS data for estimating WE potential in a more efficient way; the discussion was conducted about the potential benefits of having a city-type wind turbine in the city.

The city-type wind turbine offers a possibility to install the turbines on the top of buildings in the city and, thanks to this, residents in each building could generate part of the electricity that they need. This could potentially make the transition to WE from traditional energy sources faster, as installing this type of turbine would not require big spaces, longlasting investment planning, or any other limitations. For these purposes, within the scope of the study, WS data in an hourly format for almost the last seven years for Gda ´nsk (Poland) were obtained from a third-party provider. The two-parameter Weibull distribution (TPWD) was then fitted to WS with the help of Maximum Likelihood Estimation (MLE). Efficient Global Optimization (EGO) was used on top of MLE to find optimum parameters of TPWD. Moreover, performance of EGO was compared with performance of GA, SA, and DE, which are the algorithms that have been used by researchers in the literature to fit statistical distribution to WS. To compare the performances, root mean squared error (RMSE) and coefficient of determination (R2) were used. Parameters were obtained for each month and annual data by using each technique. Comparisons were provided. By using parameters of TPWD for annual data, potential WE was estimated for Gda ´nsk, which is the capital of Pomerania Voivodeship in Poland, for the case of having city-type wind turbine in the city center of Gda ´nsk.

The construction of the paper is as follows: Section 2 focuses on a brief history of WE in general, the development of WE in Poland, and WE potential in Pomerania Voivodeship. Section 3 describes the methodology used in the study. Section 4 covers details about dataset used in the study. In Section 5, results are discussed, while Section 6 concludes the study and provides information about potential further research studies.

### **2. Development of the WE Market in Poland**
