Floating solar PV systems have certain advantages and benefits when compared with traditional ground-mounted solar PV systems.

Alongside ground-mounted and rooftop PV, floating solar PV (FPV) is often hailed as the future third pillar of the global solar PV market. At present, among the 60+ countries actively pursuing the deployment of FPV (see Map 1 below), more than 35 countries are home to an estimated 350 operational FPV systems, which up until the end of August 2020 had a cumulative capacity of approximately 2.6 GW. Although still considered a niche, FPV is projected to experience an average growth rate of above 20% in the coming five years.

In this context, Asia is expected to account for roughly two thirds of the global demand, mostly driven by China, India, South Korea, Taiwan, Thailand and Vietnam.

Countries with current FPV installations

 

Early beginnings and motivations

Floating PV systems are not new, given that the first system (for R&D) was already installed in Aichi, Japan in 2007. The following year, the first FPV-related patent was officially registered and the world’s first commercial installation, a 175 kWp system built at the Far Niente Winery in Napa Valley, California, became operational. The owner’s primary motivation to deploy a FPV system was to avoid occupying land and to reduce water evaporation.

Geographical considerations are naturally a key driver for FPV. Countries subject to high population density, low percentage of flat terrain, competing use for available land, etc., but at the same time, home to a significant number of available water bodies, both often in proximity to load centers and existing grid infrastructures, were among the first to consider FPV systems as a way to further scale-up solar power generation capacities. Land scarcity is an ever pressing issue, as illustrated by South Korea, where 70% of the land is mountainous. During the early years, commissioned FPV systems were of a smaller scale and primarily designed for research and development purposes. Today, located in the Province of Anhui, China, the world’s largest installed FPV system currently has a capacity of 150 MW and has been in operation since November 2017.

 

Advantages and benefits of floating solar PV

Floating solar PV systems have certain advantages and benefits when compared with traditional ground-mounted solar PV systems.

To date, the global track record of operational FPV is limited. Therefore, a number of the above stated performance advantages have yet to be confirmed by larger installations, ideally over longer time periods and across varies geographies. However, first monitoring findings indicate that in many cases such benefits may outweigh the increased capital cost.

 

What are the costs of FPV systems?

Overall, costs incurred for developing a FPV system, not only vary from project to project, but are as well highly site-specific. Factors influencing the cost structure include water level variation, depth, quality and salinity. The bathymetry of the water body determines the design layout of the anchoring and mooring system. Depending on the locally prevailing wind regime, the FPV plant design requires the ability to withstand stronger wind loads.

As well the overall logistics, other factors to consider include distance to the shore, site accessibility, local infrastructure, and vicinity to the grid. Moreover, water-based electrical infrastructure not only causes higher O&M costs, but also for example, installed cabling may require a higher moisture resistance. Furthermore, due to the lack of empirical data, projects tend to require a more comprehensive technical due diligence.

Usually water bodies are subject to increased scrutiny measures imposed by relevant governmental authorities, hence developers might be required to regularly conduct comprehensive environmental impact assessments (EIA), which might be an additional cost driver. In general, the CAPEX of FPV systems are currently around 5–15% higher compared to a ground-mounted PV system, but in some European countries, a 20+ MW system is already considered competitive. Below in Figure 1 is an overview of proposed bids for various tendered FPV projects.