## 1 Introduction  
In the first half of 2024, 13 European Union (EU) countries generated more electricity from wind and solar photovoltaics (PV) than from fossil fuels. At the end of the same year, the total installed capacity in variable renewable energy (VRE) was 335 GW in solar PV [1] and 231 GW in wind energy [2]. In 2024 alone, the EU-27 installed 65.5 GW of new solar PV and 12.9 GW of new wind power plants. Wind power contributed 17.4% while solar PV contributed 11.1% to the total EU-27 electricity generation in 2024 [3]. Currently, the EU-27 is generating 47% (1300 TWh) of electricity from renewable energy and only 29% (793 TWh) from fossil fuels. This is a remarkable growth from 2019, when the EU was generating 34% (979 TWh) from renewable energy and 39% (1130 TWh) from fossil fuels [3]. Power-sector carbon emissions have fallen by 26% over the past five years. Currently, the solar PV sector in the EU-27 is experiencing exceptional growth and is expected to reach 800 GW of installed capacity by 2030 [1]. The total wind power is projected to reach 351 GW by 2030 [2]. Since 2010, solar PV has experienced a dramatic decline in manufacturing and installation costs. Today, utility-scale solar PV is the most competitive power plant option, with a global average levelized cost of electricity (LCOE) 50% lower than the cheapest fossil fuel alternative. For newly commissioned utility-scale solar PV projects, the LCOE dropped from 460 US$/MWh in 2010 to 44 US$/MWh in 2023--a 90% decline [4]. Figure 1 compares the total installation costs (TICs) and the LCOE for various renewable energy technologies between 2010 and 2023. Half of the cost reduction of solar PV is attributed to the decreasing price of modules, while improvements in module efficiency, optimized manufacturing and supply chains, and reduced mounting costs have also contributed to the cost decline. Between 2010 and 2023, the average TIC for utility-scale solar PV fell from 5310 to just 758 US$/kW\({}_{\text{p}}\)[4]. In 2023, the global average LCOE for onshore wind was 25% lower than the LCOE of solar PV (33 vs. 44 US$/MWh). However, onshore wind had a 50% higher TIC (1160 vs. 758 US$/kW\({}_{\text{p}}\)). The LCOE gap between onshore wind and solar PV is expected to reverse by 2030 [5]. In 2024, wind contributed 14.9%, while solar PV only contributed 3.5% to the electricity mix in Croatia [6; 7]. To put it into context, the per capita electricity generation from wind and sun in Croatia is 676 kWh/cap, only half of the EU-27 average value of 1410 kWh/cap [8]. The delayed growth of the solar PV sector in Croatia is a consequence of the intricate permitting processes and the underdeveloped power grid. Simplified permitting and faster grid connection procedures could accelerate the deployment of new solar PV installations. At the end of 2022, the total solar PV capacity in Croatia was 220 MW, then it expanded up to 498 MW at the end of 2023 and to 878 MW at the end of 2024 [9; 10]. By the end of 2024, a total of 25,406 solar PV units were operating in the category of self-consumption, while only 6 solar PV units were utility-scale power plants feeding electricity to the public grid [11]. The total installed capacity in the self-consumption category was 776.1 MW: 19,022 solar PV units (134.4 MW) were rooftop installations, generating electricity for households and 6384 solar PV units (641.7 MW) were generating electricity in the commercial category [12]. The total installed capacity of the six utility-scale solar PV power plants was 101.7 MW. Utility-scale solar PV power plants are connected to the transmission grid (110 kV), while self-consumption units are connected to the distribution grid (up to 35 kV). Solar energy oversupply from the self-consumption category is exported to the public grid. The utility-scale solar PV sector is expected to grow substantially in the next years.