In Europe, more than 75% of buildings are energy inefficient according to current energy standards. These buildings account for 40% of total energy consumption. Therefore, addressing the energy efficiency of existing buildings through various renovation measures remains of critical importance. In this study, two differently renovated multi-apartment buildings were selected to evaluate its environment impact using life cycle assessment. The buildings were built during the early 1980s, which did not meet the current energy efficiency standards. In recent times, these buildings were revised by Governmental agencies through the modernization process. The aim of the assessment is to study the environmental impacts associated with different renovation measures that has been carried out. This assessment covers the impact of new materials added, and the operational energy use. The study reveals that renovation stage accounts for 19% CO₂ emission. The renovated buildings with renewable measures have a significant impact over climate change than the conventional renovation measures. Moreover, the potential savings in thermal energy used for space heating and domestic hot water preparation are 25% and 40% after conventional and renewable measures renovation, respectively. It was concluded that the total climate change potential could be reduced from 12% and 48% by retrofitting combined with renewable energy measures.

Analysis of wind power utilization efficiency around the world and Europe has revealed the gap between feasible and factual power generation. The paper presents an investigation of wind power generation dynamics, penetration levels into the electricity system, and dependence of capacity factors on the hub height and the rotor diameter of wind turbines in the Baltic States. These factors are the main for the evaluation of wind power utilization efficiency. Wind power penetration levels show that possibilities of the energy system to accept more wind power installations in the Baltic States are far away from its limit. Besides, dependence of high wind turbines capacity factors’ on the hub height and the rotor diameter in the range of 20–120 m was revealed.