PROJECT DESCRIPTION
BACKGROUND
The European Environmental Agency estimated that around 30% of EU citizens and 20% of Europe’s territory is affected by water stress on average every year, reflecting increasing drought and scarcity pressures associated with climate change.
Agriculture accounts for around 22.5% of the total freshwater abstracted in the EU, with significant differences between Member States. In arid or semi-arid conditions (typical for southern EU), irrigation accounts for nearly 80% of agricultural water use. Agricultural water reservoirs (AWR) play a significant role for water supply in agricultural irrigation systems in Europe, especially in areas where water scarcity is a critical issue, such as the south of Spain. AWR are open to the atmosphere, leading to significant water losses, limiting opportunities for effective water saving. In the Segura basin alone, annual losses amount to 78 cubic hectometres (Hm3), with evaporation affecting between 6.5% to 11.7% of the water stored in the ponds.
However, existing solutions to minimise this loss are not cost effective for agriculture. Moreover, the sector’s energy demand has increased with the adoption of more efficient irrigation systems, and energy supply is problematic in remote areas. This has led to the installation of solar panels on AWR to generate clean renewable energy and offset costs. While the panels partially cover AWR and help to reduce evaporation, they still do not provide a cost-effective solution.
In addition, AWR are vulnerable to excessive algal growth (eutrophication) which impairs water quality and can produce unpleasant odours. Algal proliferation can also clog pumps, filters and pipes, while its decomposition depletes dissolved oxygen, further degrading water quality and potentially promoting the release of phosphorus and other nutrients, as well as metals such as iron, from sediments. Although a range of methods is available to treat algal blooms, their effectiveness is highly variable and warrants further research. A common approach is to cover the basins with windbreakers or floating covers on the water surface.
OBJECTIVES
The LIFE H2OLOCK project aimed to demonstrate a versatile and cost-efficient solution specifically designed for medium to large-scale AWR, capable of reducing water evaporation, suppressing algae growth without the use of algicides (after 15-30 days of operation), and generating renewable energy for irrigation systems.
The objective was to improve evaporation performance from the current 80% achieved with existing solutions to 85-90%. These goals would be achieved through the application of a novel combination of floating modules, floating blankets and flexible solar cell panels integrated into the floating blankets. This approach would help to reduce pressure on water resources, promote sustainable water management and support the agricultural sector’s transition towards sustainable, renewable energy.
Specifically, the project aimed to:
- demonstrate the technical feasibility of the cost-effective integrated solution,
- implement photovoltaic panels on AWR covers that fully supply irrigation energy demands (production of at least 50 W/m2), thus demonstrating an energy solution that is particularly attractive for farmers in isolated areas or developing countries with intermittent access to fuel for generators,
- reduce costs by 30% compared with the installation and maintenance of conventional technologies, with the aim of keeping costs below €9/m2 by the end of the project,
- demonstrate a versatile system design and configuration that can be transferred to all types of AWR across Europe and elsewhere regardless of climate and weather conditions,
- carry out a lifecycle analysis to show the environmental and social benefits of the solution.
RESULTS
The project was implemented successfully. By April 2024, pond covers had been installed at the Spanish sites – La Jeresa (27 000 m²) and La Jarosa (1 500 m²) – and at the Portuguese site (10 200 m²). In addition, the solar plants were installed in 2024 (34 kWp at the Spanish site and 20 kWp at the Portuguese site).
After more than one year of monitoring the covers’ performance, the solution achieved an average evaporation reduction of 79.85%, with summer peaks exceeding 84%, and no chemical algicides were required to maintain water quality. It is envisaged that the covers will remain in place at the project sites for their full service life, thereby delivering positive environmental impacts for years to come. The results of the Life Cycle Analysis and the Life Cycle Costing showed a better performance of the H2OLOCK solution than their main competitors.
The market and business case are among the project’s principal strengths. The project has devoted significant efforts to commercialising the solution: 85 replicas were sold during the project period, covering an additional 149 808 m² of ponds. This equates to annual savings of more than 230 000 m³ of water, energy savings of 1.94 GWh/year and avoids the use of more than 120 tonnes of algicide per year. This has been possible thanks to the competitiveness of the solution, with costs at least 33% lower than other modular solutions on the market standing (€11-12/m2 vs €15-40 /m2 of their competitors).
The project also completed realistic replication, transferability and business plans. A further 230 replicas are planned by 2028 (an additional 405 260 m² of ponds covered), with an expected annual turnover of €1.7 million by 2029 for the project beneficiary (ARANA).