Hydraulic power: clean electricity thanks to dams and waterfalls

12% of the electricity generation recorded in Spain was of hydraulic origin in 2021, when this source accounted for approximately 25% of the total renewable contribution to the national mix.

Hydraulic or hydroelectric power is a clean resource resulting from the use of kinetic energy and potential of currents, waterfalls or tides.

Electricity is obtained at power plants, which dam water from rivers and then release it in a controlled manner, turning turbines and generating electricity.

Hydraulic power It accounts for 12% of Spain’s electricity generation in 2021, with 29,592 gigawatt hours (GWh), contributing 24.8% of the renewable generation mix. And being, for another year, the second most important renewable resource in the system,” he explains Craig James Menzies, Head of Energy at environmental consultancy Global Factor.

This position has remained unchanged since 2009, when hydro replaced wind as the number one renewable source in the national electricity mix.

“The hydraulic generation is highly variable, reaching 40,000 GWh in wet years, while halving in dry years,” the expert added.

The Spanish system has 17,093 MW of installed hydropower, which represents 15.9% of the country’s total capacity and 27% from renewables.

This means that it is the second clean technology with the largest installed capacity after wind power. However, hydroelectric power has hardly changed in the past 20 years, while the capacity of other technologies such as solar power and wind power has changed dramatically.

The first in the world

Hydropower is also the most widely used renewable electricity generation technology worldwide due to its maturity and reliability.

“Its use allows access to a cheap, carbon-free source of electricity, and if the plant has a large-capacity reservoir or reservoir, it makes it possible to provide flexible services to the electricity grid,” explains Menzies.

This allows the hydraulic power plants to contribute to the frequency control of the electrical system, providing balance and acting as active reserves (Spinning reserves). All this increases the economic viability of the plants by increasing the income of the owners.

In addition, depending on the size of the tanks or tanks, these facilities can serve as warehouses for weeks, months, or entire seasons.

generally , Hydropower has relatively low variable costs and other disparate combinations, depending on the site and other site conditions.

The competitiveness of European hydropower plants is very high, according to the LCOE: between 2016 and 2021, it ranged between $60 and $1,270 per MWh, with an average of $110 per MWh.

However, Spain will not make major investments in this technology in the coming yearsAccording to the National Integrated Energy and Climate (Pniec) plan. It only plans to increase the current installed capacity by 500 MW until 2030.