Portugal’s Alto Rabagão floating solar farm becomes a storm test site for self-adjusting mooring buoys and 3D-printed concrete anchors
When it comes to technology, the weather does not care how clever it is.
While the water may be calm one minute, this can change suddenly to being windy with big waves – something that carefully engineered structures have to be able to withstand.
With renewable energy efforts becoming increasingly ambitious, people have to consider: what do you do when nature refuses to play nice?
2016 marked the start of EDP’s floating photovoltaic pilot at Alto Rabagão, where it pioneered a model allowing solar and hydropower to share infrastructure.
When solar takes the plunge
EDP is putting this to the test at Portugal’s Alto Rabagão reservoir, where it has opened the Floating PV Lab.
There, developers can use an operating hydropower and solar environment to see how equipment behaves when exposed to the elements.
The location was not chosen at random.
2016 marked the start of EDP’s floating photovoltaic pilot at Alto Rabagão, where it pioneered a model allowing solar and hydropower to share infrastructure.
The setting of this particular reservoir is a demanding one, as it sees strong winds, waves, snow, ice and fluxtuations in temperature.
In other words, this is not so much a gentle product demonstration than it is an energy-tech obstacle course.
Floating solar meets its match
Yes, the setting is harsh. But that is precisely the point.
As reservoir levels change, floating solar platforms need to remain stable, with anchors and moorings coping with the wind and waves.
This is why real-world testing is so important, as it can help to expose weaknesses, refine designs and reduce risks.
That opportunity to learn is now available beyond just one company with EDP’s lab, which allows businesses and research partners to find solutions that could help to make these innovations suitable for commercial use.
Two clever solutions to one choppy challenge
How, exactly, do you keep a floating solar farm from becoming a floating-away solar farm?
Currently, two solutions are being explored by EDP at Alto Rabagão: one to address the challenges of mooring, and the other anchoring.
One of these experimental projects is a buoy that is able to adjust to changing water levels, with the second one giving traditional concrete anchors a modern makeover.
A buoy that goes with the flow
An automatic tension buoy for floating photovoltaic systems is being tested by Norwegian company, Fred. Olsen 1848.
The objective with this buoy is that it will be able to maintain the right amount of tension in the mooring arrangement.
The varying levels at Alto Rabagão make this the perfect place to put new technologies to the test, revealing how systems must adapt.
Printing a solid foundation
Gravity anchors made with 3D-printed concrete are also being trialled by California-based company, Sperra.
Their geometry is able to be customised to fit site-specific loads, mooring configurations and ground conditions.
The benefits of this are that it could improve performance and reduce the cost and complexity, making installation more efficient.
Now it’s time to weather the storm
Both of these pilots will be running for a year and, if any of these concepts are validated, the solutions could end up featuring in floating-solar installations in the future.
With a goal of supporting the commercialisation of at least five new technologies by the end of 2027, EDP will be operating the lab for three more years.
A little turbulence, a lot of potential
When considering the future of floating solar, it’s about more than just shiny panels and bright ideas.
It’s also about the engineering that keeps them secure and functioning when the weather gets rough.
With EDP opening Alto Rabagão to shared experimentation, difficult conditions are being turned into useful data in a collaborative setting.
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