Hydropower is an already established technological way of renewable energy generation. In the industrial and surface water rich countries, the full-scale development of hydroelectric energy generation by turbines at large-scale dams is already exploited to the full limit, and consequently, smaller hydro systems are of interest in order to gain access to the marginal resources. The world's total annual rainfall is, on average, 108.4 x 1012 tons/year of which 12 x 1012 tons recharges the groundwater resources in the aquifers, 25.13 x 1012tons appears as surface runoff, and 71.27 x 1012 tons evaporates into atmosphere. If the above rainfall amount falls from a height of 1000 m above the earth surface, then kinetic energy of 1.062 x 1015kJ is imparted to the earth every year. Some of this huge amount of energy is stored in dams, which confine the potential energy so that it can be utilized to generate hydroelectric power.
Wilbanks et al. (2007) stated that hydropower generation is likely to be impacted because it is sensitive to the amount, timing, and geographical pattern of precipitation as well as temperature (rain or snow, timing of melting). Reduced stream flows are expected to jeopardize hydropower production in some areas, whereas greater stream flows, depending on their timing, might be beneficial (Casola et al., 2005; Voisin et al., 2006). According to Breslow and Sailor (2002), climate variability and long-term climate change should be considered in siting wind power facilities (Hewer 2006).
As a result of climate change by the 2070s, hydropower potential for the whole of Europe is expected to decline by 6%, translated into a 20 - 50% decrease around the Mediterranean, a 15 - 30% increase in northern and eastern Europe, and a stable hydropower pattern for western and central Europe (Lehner et al., 2001).
Another possible conflict between adaptation and mitigation might arise over water resources. One obvious mitigation option is to shift to energy sources with low greenhouse gas emissions such as small hydropower. In regions, where hydropower potentials are still available, and also depending on the current and future water balance, this would increase the competition for water, especially if irrigation might be a feasible strategy to cope with climate change impacts on agriculture and the demand for cooling water by the power sector is also significant. This reconfirms the importance of integrated land and water management strategies to ensure the optimal allocation of scarce natural resources (land, water) and economic investments in climate change adaptation and mitigation and in fostering sustainable development. Hydropower leads to the key area of mitigation, energy sources and supply, and energy use in various economic sectors beyond land use, agriculture, and forestry.
The largest amount of construction work to counterbalance climate change impacts will be in water management and in coastal zones. The former involves hard measures in flood protection (dykes, dams, flood control reservoirs) and in coping with seasonal variations (storage reservoirs and inter-basin diversions), while the latter comprises coastal defense systems (embankment, dams, storm surge barriers).
Adaptation to changing hydrological regimes and water availability will also require continuous additional energy input. In water-scarce regions, the increasing reuse of waste water and the associated treatment, deep-well pumping, and especially large-scale desalination, would increase energy use in the water sector (Boutkan and Stikker 2004).
Was this article helpful?