David Appleyard Chief Editor
Huge floods that have swept through Central Europe have pushed hydropower development and its role in managing water flows to the top of the political agenda. At least a dozen deaths have been reported in the region as the major rivers of Germany, Austria, Hungary, Slovakia and the Czech Republic, swollen with unseasonally heavy rainfall, have burst banks and inundated vast swaths of the countries concerned.
Tens of thousands of people have been evacuated, and Germany's Chancellor, Angela Merkel, has promised some EUR100 million in emergency aid. Of course, the true economic costs of such a disaster are inevitably many, many times more than this.
As an example, floodgates on a system of nine dams called the Vltava Cascade in the Czech Republic were opened as water levels peaked, in a bid to stop flood defences failing in Prague. Projects in this system include 120 MW Lipno 1, 364 MW Orlik and 144 MW Slapy and represent more than 17% of the total installed capacity of national utility group CEZ a.s. Suspending operations at these plants even for a short period is clearly a major economic blow for such a company, and this is before any consideration of the human cost, damage to equipment and infrastructure or repairs that may be required.
The role of hydropower in flood projection and power generation was highlighted at the recent Renewable Energy World Europe event, which took place in Vienna, Austria — within a few hundred meters of the Danube — and a technical tour to the Gabcíkovo waterworks system in Slovakia.
Owned and operated by Enel subsidiary Slovenské Elektrárne a.s., Gabcíkovo was originally conceived as a cross-border development — the Waterworks System Gabcíkovo-Nagymaros — as a common investment between Czechoslovakia and Hungary. However, after withdrawal of Hungary from the project in 1989, only the Gabcíkovo part was completed after a substantial redesign that saw 4 meters cut from the maximum available head and a smaller reservoir. The project as completed nonetheless serves in multiple roles, including flood protection on the Danube from Bratislava to Štúrovo in Slovakia, transportation services and electricity generation.
Gabcíkovo consists of the Cunovo stage with its inlet channel and the Gabcíkovo stage with an exit channel and a 720 MW power plant. Depending on the flow of the Danube, Gabcíkovo generation varies between 1.8 to 2.8 TWh annually and represents 10%-12% of total Slovakia electricity consumption. However, had the project been completed as originally envisaged, annual generation would have been about 500 GWh higher.
This would have been a substantial economic benefit. But perhaps the key message is the importance of the political and economic engagements and agreements such cross-border developments entail. This a reflection of the cross-border nature of hydrological resources as much as anything else — and, as such agreements are always challenging, they can, as seen with the Gabcíkovo-Nagymaros plans, fail despite good intentions.
But perhaps the potential impact on flow management and the role such a cross-border projects could play in the event of extreme events, such as those recently witnessed in Central Europe, will in future bring focus and accord to those politicians who face each other across the negotiating table.