3. The Current Situation and Perspectives on the Use of Hydropower for Electricity Generation

According to IEA sources, the cost of power production from hydropower can vary widely depending on project details, but usually fall into a range between US$50 and US$100 per MWh.

There are different possible causes and places for losses in hydropower plants: Unused drop height, friction in the galleries and tubes, and inefficiencies in the turbines. The losses due to frictions are estimated to 5 % on average (Bischof 1992), while the turbines cause losses between 9 and 13 %, depending on their age. It is assumed that today the average efficiency of generators operated in hydroelectric power stations is 97 %.

In Europe, nearly 40 % of the economically viable hydropower potential is not being tapped, although hydropower is the dominant renewable electricity source in the world and also in Europe.

It is expected to generate by hydropower plants worldwide a total of 1,476 TWh in 2020 and 1,592 TWh in 2035.

Certain EU Directives, including Directive 2000/60/EC, known as the Water Framework Directive (WFD) and so-called Habitat Directives 92/43/EEC and 2009/147/EC, also show an adverse impact on the development of hydropower in the EU. Contrary to the expectations of numerous stakeholders, the WFD does not regulate the principles of rational management of water resources. Instead, the main emphasis is put on the rules for their protection, including improving the quality of water bodies. Strict implementation of WFD provisions has led, among other effects, to a clash with recommendations of Directives 2001/77/EC and 2009/28/EC on the promotion of renewable energy sources. The Habitat Directives have provided the basis for the Natura 2000 program, which covers almost 20 % of Polish territory, including the entire Lower Vistula (Wisła) valley. Implementation of capex projects in these areas is extremely difficult. Not only the appropriate environmental compensation is required, but also evidence that the project is essential due to an important overriding public interest (Steller 2013).

According to the Situation Report on Hydropower Generation in the Alpine Region Focusing on Small Hydropower (2011), carbon dioxide is the most important anthropogenic greenhouse gas. The primary source of the increased atmospheric concentration of carbon dioxide since the preindustrial period results from fossil fuel use. Carbon dioxide emissions from fossil fuel use also occur in the course of the generation of electricity, mainly due to combustion processes in thermal electric power plants and gas power plants, whereas the generation of electricity from hydropower can be considered as a form of electricity generation that is nearly free from greenhouse gas emissions. Therefore, the substitution of hydropower for electricity generation within the European energy mix with is often used in calculating the “savings” of greenhouse gas emissions. Expressed in CO₂ equivalents, every kilowatt per hour from hydropower (emissions of 4 g CO₂/kWh) would, therefore, replace one kilowatt per hour from the UCTE mix (emissions of 500 g CO₂/kWh). Based on these figures, hydropower would result in approximately 100 times less CO₂ being emitted compared to the current UCTE mix.

Hydropower plants may, depending on their design, provide electricity for base load and/or peak load. They are particularly valuable for meeting peak demand situations, as they are more responsive than other generation sources and can be started or stopped within a very short time. Hydropower units are also able to rapidly increase or decrease their output—at least 10 times faster than conventional power plants.

Different types of electricity generating plants are differently suited to operation as base-load plants or peaking units. In general, nuclear power plants, run-off-river plants, and conventional thermal power plants are covering the base-load demand. Utilities such as gas-fired power plants and hydro storage power plants cover the peak-load demand. Pump storage facilities are the only renewable energy source, which can support the system by highly flexible power generation ancillary services and peak-load generation. Pump storage power facilities are enabled to replace renewable or thermal power plants from base-load to peak-load generation (RESAP 2011).

Multi-purpose hydropower projects could also provide services beyond the electricity sector. They contribute to improved water management, such as flood and drought control, which could prove especially valuable in the context of climate change adaptation. As for the decarbonization agenda, hydropower has been identified as highly valuable for climate change mitigation, due to its low-carbon footprint and high-generation efficiency. This makes hydropower the most competitive and reliable renewable energy source (RESAP 2011).

A total of 8 % of the US$6.8 trillion to be invested during the period 2011–2020 and the same percentage of the US$10.1 trillion to be invested in the period 2012–2035 should be for the construction of new hydropower plants.

In Austria, in 2011, there were 15 pumped storage power plants with a total pumping capacity of 2‚598 MW in operation. There is still considerable potential for the development of pumped storage power plants in Austria. A number of projects with total pumping capacity of 1,115 MW have obtained licenses; some of these plants are already under construction. Moreover, there are concrete plans for the installation of additional 3,075 MW of pumping capacity—if they were realized, the total capacity in Austria would increase to 6.8 GW—more than any European country disposes of today (RESAP 2011).

A total of 338 flow hydropower plants and 102 storage hydropower plants.

The main renewable contribution in the Belgian energy mix comes from biomass and waste sources.

The renewables installed capacity represents 23.41 % of the total energy capacity installed in the country.

To meet EU requirements for renewable energy generation, Bulgaria must ensure that 16 % of its gross energy consumption is generated from wind, solar, and other renewable sources by 2020. According to Bulgaria’s National Renewable Energy Plan (NREAP 2010), in 2010, the overall share of renewable energy sources used in heating, cooling, electricity, and transport stood at 10 % of total energy usage in the country, up from 9.2 % in 2005, which is used as a base year (Todorova 2011).

In 2010, there were 136 small hydropower plants operating in the country and a total installed capacity of 263 MW (generating 630 GWh) providing 14.31 % of the electrical energy produced from renewable energy sources. By 2020, the aim is to have 200 small hydropower plants with a total installed capacity of 380 MW (1,050 GWh); this represents an increase of 44.5 % respect to the capacity installed in 2010 and 66.7 % respect to the generation of electricity in that year. The technically and economically feasible potential is 755 MW and is able to generate 706 GWh per year. So far, about half of the economically feasible potential (44.3 %) has been developed (Liu et al. 2013).

The installed capacity in Croatia is around 1,500 MW for hydropower storage plants and around 373 MW for run-of-river plants, resulting to an electricity production from hydropower sources of 8,309 GWh in 2010. The total installed small hydropower capacity amounts to 39.65 MW. The definition for small hydropower plants in Croatia is less than 10 MW of capacity (Liu et al. 2013).

In 2008, the total economically feasible small hydropower potential was calculated at 465 MW, which means the remaining economically feasible potential was 168 MW. In this figure, the 43-MW planned small hydropower plants are not included (Punys and Pelikan 2007).

Most of Finland’s small hydropower plants are run-of-river plants, which have no or relatively small water storage capacity. These plants normally operate on base load and use cumulative flow continuously. Only a very small number are penstock or canal plants (Liu et al. 2013).

The overall technical potential has been assessed at 95 TWh per year, but taking the strongest environmental protection in full account brings the total to 80 TWh—still a 19 % increase from current level (Dambrine 2006).

The generation of electricity could reach 99 % of the total electricity generated in the country in a single year.

According to the capacity installed, the country occupies the place number 24 at world level (0.67 % of the total) and the place number 9 at the regional level (3.80 % of the total).

A more realistic potential was estimated at about 64 TWh per year (Williams 2011).

In 2010, this figure was 13 %.

From 2007 onward, not many new plants have been built, but refurbishment is being made, including upgrading larger small hydropower plants. For smaller small hydropower plants with higher cost per produced kWh, the outcome for investment is more unsecured.