HydropowerThe hydropower sector uses hydro-meteorological predictions to guarantee people safety and dam security, and to optimise energy production and the economic value of water resources.

Accurate and reliable weather forecasts are needed over a wide range of space and time scales:

  • Short-term streamflow forecasts (2-3 days ahead) for flood protection and the security of installations.
  • Medium-range forecasts (7-15 days ahead) for the optimisation of production.
  • Long-term (months ahead) predictions for water resources management and environment protection during drought periods.
  • Hydrological trends and outlooks under future climate conditions for anticipating the effects of expected changes in runoff volume, extremes and seasonability, which directly affect hydropower generation.

Hydropower has the advantage of being a renewable source of energy that can be stored and reallocated in space and time. Storage allows handling the natural variability of hydro-meteorological hazards and extremes.

Hydropower water storage reservoirs, however, operate often for multiple purposes (e.g. domestic/agricultural water supply, environment protection, tourism, flood protection, etc.) and conflicts of use may arise when resources are scarce. Available forecast information, optimisation tools and adaptive strategies help to inform operational decision-making.

In this sectoral survey, we evaluated the impacts of improved predictability of hydro-meteorological events on the hydropower sector at different temporal scales.

Four sites in Europe, covering different hydro-climatic and socio-economic contexts, were included to capture the diversity of conditions encountered in hydropower management:

  • South-East French catchments;
  • The Lake Como in Italy, a typical snow-dominated Alpine basin;
  • The Jucar River basin in Spain, a typical south Mediterranean basin with an important share of water for irrigated agriculture (80%) and conflicts on water allocation in a multi-reservoir system; and
  • The upper part of the River Umeälven in Sweden, a typical north European catchment.



A survey on weather and climate services for hydropower 

The IMPREX team has designed a survey with the aim of collecting your viewpoint on the need for and the value of weather and climate services for the hydropower sector in Europe and internationally. The purpose was to help us to improve current forecast products and enhance their usefulness.

All answers were treated confidentially and anonymously.

Thank you in advance,
The IMPREX WP 8 group

For more information about the past survey please contact Andrea Castelletti andrea.castelletti@polimi.it


Report on needs in the hydropower sector

This report aims at reviewing the existing knowledge and needs for weather and climate services in the hydropower sector. It presents the results of a survey designed to objectively assess the current practices and future needs of the hydropower industry. The survey results show that all 11 respondents have already been using forecasts products of various forms.

Public free weather and climate services tend to be the main data source to retrieve forecast information, and the majority of the respondents hold a positive evaluation of the quality of current products. In addition, respondents expect future improvements to be focused on enhancing the forecast of extreme events and extending the forecast lead-time.

Read the full report on needs in the hydropower sector.

Hydro-meteorological indices

The aim of this report is to quantify and improve the skill of seasonal forecasts, in particular in regard to the forecasting system based on the EC-Earth climate model. We show that dynamical seasonal forecast systems are as good and in some instances better than a statistical model in forecasting drought conditions as represented by the standardized precipitation evapotranspiration index (SPEI).

We also show that initializing the climate model with realistic soil moisture improves the forecast skill over Europe, with the largest increase, detected for temperature over Eastern Europe. We also show that soil moisture initialization improves the skill of two climate indices relevant to the agriculture sector, SPEI and heating degree days. This leads to skilful seasonal forecasts of maize yields for certain European countries. Finally, we investigate the impact of increasing model resolution on the forecast skill of the North Atlantic Oscillation and blockings. We found some hints of improvement, but the limited ensemble size and number of start dates considered were not sufficient to assess, in a robust way, the changes in the forecasting skill of these phenomena.

Read the full report on hydro-meteorological indices.