## 2 Background for Own Research
This phenomenon is most present in markets with higher integration of renewables and with less consumption flexibility or insufficient storage capacity. The impact of RES on volatility is not the same in every country--it depends on the following factors:  
1. Measures of connectivity with neighboring markets (interconnectivity);
2. The existence of support services;
3. The degree of market liberalisation and regulatory instruments. From 2015 to 2022, overall volatility will increase by 30-50%, especially in countries such as Germany, Denmark, Spain, and Australia. This trend is directly linked to the increasing penetration of RES and changes in demand patterns. The authors recommend the implementation of dynamic pricing, flexibility support (e.g., batteries), and time-sensitive demand response as the main tools to dampen volatility. Without these measures, there is both a risk of diminishing economic returns for producers and a risk of price uncertainty for consumers. According to a 2022 study [16], increasing the share of RES in Europe leads to a decrease in the average price of electricity. However, the impact on price volatility is not clear. In some cases, volatility increases, in others it decreases, depending on the specific market conditions. The authors analysed 31 European countries over the period 2010-2021 and showed that the increasing share of RES (particularly solar and wind) is fundamentally changing the price dynamics in electricity markets. Solar has a significantly higher impact on intraday volatility than wind, mainly due to its concentrated production during the day. Solar energy, unlike wind energy, has clearly defined times when it can be used--PV plants do not produce at night. In contrast, wind power plants can generate electricity at virtually any time during the day. Statistically significant results show that every 1% increase in the share of RES leads to an increase of price volatility (standard deviation) from 0.4 to 0.6% on average. Countries such as Germany, Spain, Denmark, and Italy experience the highest fluctuations. Due to the lack of demand flexibility and weak energy storage infrastructure, the increasing share of renewables leads to more frequent occurrences of negative prices, especially during weekends and sunny days. Although RES reduce the long-term average energy price, they increase short-term volatility, leading to cost unpredictability for both households and businesses. Markets that are poorly interconnected (e.g., in Eastern Europe) cannot efficiently absorb production fluctuations, which results in local price extremes. Improving cross-border capacity and coordinating prices between countries appears to be a key way to stabilise the market. The authors recommend that demand flexibility, development of storage capacity (e.g., batteries), smart grids, and cross-border integration are essential pillars to mitigate volatility. Without accompanying measures, paradoxically, green transformation can reduce price stability, which reduces investor confidence and prolongs the return on investment. A [17] 2025 study examined the transmission of electricity price volatility between 24 European countries. They found that volatility spillovers have increased significantly after 2022, meaning that price shocks in one country are increasingly transmitted to other countries. Renewables, particularly wind and solar, contribute to unpredictable fluctuations that spread further across border interconnections. Negative'shocks' from wind generation in Germany, for example, had an impact on prices in Poland, the Czech Republic, and Slovakia within 48 h. The authors also found that large downward price changes(declines) have a stronger transmission effect than upward price shocks. This has important implications for market stability and production planning. Countries with better network connectivity (e.g., Western Europe) are better able to absorb fluctuations. Conversely, countries with limited network infrastructure and divergent pricing mechanisms face greater volatility.