Challenges and solutions in monitoring floating solar parks

GreenPowerMonitor and Floating Solar Panels

The surface occupied by solar and wind installations continues to grow and it is not surprisingly new solutions are proposed, especially in those countries and regions with a small area available.

GreenPowerMonitor, a DNV GL company, has spent several years working in various floating solar parks, especially in Japan, where due to their geography and resources clients have seen how this could be an effective solution for the clean energy production.


The innovation of floating solar plants
Floating solar parks are one of these new solutions that have been developed in recent years. It is a very innovative system that produces solar energy in a structure that floats in an aquatic body, typically an artificial basin or a lake.

One of its greatest advantages is that solar floating panels offer a higher solar panel performance. This one normally declines as temperatures rise, however in a floating solar installation the water that host the plant panels help to cool down the solar equipment, which means that panels produce electricity at higher efficiencies in hot climates than they might otherwise.

Another advantage is that solar floating panels don’t use the land, except the limited surfaces necessary for electric cabinet and grid connections. Therefore, countries with limited areas, such as Japan or the Netherlands, are increasing the use of them.

Finally, there are also environmental benefits: the floating solar panel structure reduces evaporation from the water surface, which is particularly beneficial in areas susceptible to drought. In addition, the technology also helps reduce the presence of algae blooms in freshwater.


The challenges
In terms of monitoring and controlling, floating solar parks do not differ too much from the solar project we held on the ground. The PCS remain onshore, which makes the monitoring and controlling of signals from the equipment and cubicle like other projects.

The main difference is the island-based equipment (chain monitoring and weather stations). However, there are some challenges to consider:

  • Higher temperature: the boxes are usually located without any shade and facing the sun during the day with the heat in the island, therefore the temperatures reached are higher than other ground-mounted or rooftop projects.
  • Noise in communication lines: due to the site being in the water, we have experienced a higher degree of communication issues in the RS485 lines.
  • Accessibility to the site: HS requires at least the presence of two people on-site to comply with its regulations.

To solve the problems caused by high temperatures, we have designed some of the enclosures to have an exhaust ventilation system to keep temperatures lower and selected equipment with extended temperature range (up to 75ºC).

Regarding the noise in the communication lines, our knowledge has allowed us to change slightly the design of its enclosures to shorten the wiring distance with the devices using this protocol and include converters in Fiber Optic/Ethernet to bring the signal up to shore, which was a very successful solution.

Related to the accessibility problem, we have planned every action or troubleshooting in order to have enough support and resources to access the island accordingly and make the works required.


Our expertise
GPM currently monitors 8 floating solar parks in Japan for a total of 10MW, with plants ranging from 2.5 MW to 632 KW. Besides, we control more than 2.4GW in the APAC region, over 32GW globally.

The monitoring of the floating solar parks is carried out through the GPM Portal solution, which allows the clients to monitor the plants in real-time and to centralize all the plant production data and status information. In addition, to meet the requirements of the local operator, some of the floating solar parks in Japan have also our GPM Power Plant Controller, which match the schedules for curtailment mandated by the local utilities in the southern prefectures recently.

Thanks to the GPM PPC, full regulation and direct control are ensured over all devices, allowing full integration with grid operators, since the software can communicate and provide the flexibility to adapt to each local operator requirement.

According to Albert Carrera, our Regional Manager APAC:

“We at GPM started working in floating solar projects in 2016 where we commissioned our first project in Japan. Since then, we have to learn on this recent technology and evolving our solutions and designs thanks to the feedback and support of our customers. Currently, we are looking at several projects in South East Asia where we see a big potential for these kinds of projects in order to share our expertise with companies entering into this space”.

If you want to know more about our expertise, contact us:

Albert Carrera
Regional Manager APAC