IMPACT OF URBAN EXPANSION ON WIND ENERGY POTENTIAL IN RURAL REGIONS OF LITHUANIA

Abstract

Wind energy is one of the main renewable sources in Lithuania. Rural regions are suitable for wind farms due to open landscapes, good wind conditions and low settlement density. Previous research focused on climate change, but the effect of urbanisation was rarely analysed. This study evaluates how different urban growth rates change wind characteristics and electricity generation. The analysis used wind speed observations from 22 meteorological stations (1990–2020). These data were combined with projections from seven global circulation models under three Representative Concentration Pathway (RCP) scenarios: RCP2.6 (minimal emissions), RCP4.5 (medium emissions, current policies trajectory), RCP8.5 (high emissions). Urbanisation was represented by three growth rates: slow (200 years), moderate (100 years) and fast (50 years). They correspond to increasing surface roughness and turbulence. Wind speeds were calculated for hub heights of 100 m and 150 m. Two turbine types were considered: Enercon E-112 and E-126. Energy yield was estimated for a 25-year turbine lifetime. The results show that climate change has only a small impact. Wind speed decreases by less than 8%, and electricity generation declines only slightly. Urbanisation has a much stronger effect. Energy yield falls by 28–32% under slow expansion, by 39–45% under moderate expansion, and by more than 50% under fast growth. Coastal regions remain the most productive, but inland areas are more vulnerable. Higher turbines increase output, but they cannot compensate for roughness. Assessments that ignore urbanisation tend to overestimate long-term wind energy potential. Including land-use change gives more realistic information for rural development, energy planning and spatial policy in Lithuania.