With almost 12,000 solar panels, the Alqueva floating solar park is almost ready to go into production. Built in the Alqueva reservoir, Western Europe’s biggest artificial lake, this innovative project developed by EDP is an important contribution to expand renewables in Portugal and to cut reliance on imported fossil fuels.
The floating solar park now placed in Alentejo region, in the south of Portugal, was moved in the beginning of May to the definitive area of the reservoir, where it was anchored to be connected to the grid. With the size of four soccer pitches that occupy only around 0.016% of the total area of the reservoir, the plant should start producing energy as of next July – with a capacity of 5 MW, it will produce around 7,5 GWh/year and the expectation is that it will supply the equivalent of more than 30% of the families in the region.
Floating solar is an innovative technology that is expanding globally, and in this case, it is reinforced by the concept of hybridization – combining hydro (from the hydropower plant of Alqueva) and solar energy (from the floating plant) using only one point of access to the electricity grid. The solar power plant in Alqueva includes yet another innovation, which is the installation of batteries with a storage capacity of around 2MWh.
Added to this is the partnership with the Portuguese company Amorim Cork Composites, which has developed another innovation with floaters: they include cork composites and will be tested for the first time in this solar park. It’s a unique blend of recycled plastic with cork composite that contribute to reducing the CO2 footprint of the project – for instance, 30% of the floaters weight is CO2 captured in cork forests (carbon balance). The ambition is that this type of platform can become neutral or even negative in CO2 footprint. These floaters are produced by the Spanish company Isigenere.
This type of floating solar technology presents relevant economic, social and environmental advantages. First of all it avoids land occupation and therefore eliminates the need for deforestation, which would have a strong impact on biodiversity and local ecosystems, and leaves the land free for other activities, like agriculture. The integration with an existing power plant and grid connections also avoids the construction of new transmission and distribution lines and the consequent land occupation – hybridization also allows the doubling of the energy flow at the same point, without the need to increase the capacity of the line.
As it was demonstrated by the pilot project in the Alto Rabagão, that EDP started five years ago (the first in Europe to test how hydro and solar power could complement each other), the production of electricity from a floating power plant benefits from favorable temperature conditions, particularly in periods of high solar and wind resource – this happens because the lower temperatures near the water surfaces allow the temperature of the photovoltaic panels to be reduced, increasing their efficiency (cooling effect). Benefits of up to 10% have been shown in the pilot project, and an annual average of around 4% compared to equivalent fixed and land-based solutions.
Any changes in the aquatic environment are also not perceptible (result of environmental impact studies) – even the mooring system is made so as not to affect the riverbed and, even if the park is removed, the water mirror and surroundings remain as before, with no impact.
The economic viability of this project will be ensured by its scale and the hybridization component, which will allow the combination of different technologies to guarantee a balanced price level. And for EDP, it is a project developed in line with its strategy of being 100% green by 2030 and increasing investment in innovation and renewable projects.
