Interview: Floating PV is poised to make a splash, says SERIS

pv magazine: What is you understanding of the amount of floating solar that has been installed? Where has it mostly been installed?
Lu Zhao: Most of the capacity installed so far is in China, Japan, the U.K. and South Korea.
As part of the Top Runner Program, 1 GW of floating PV was tendered in 2016 at Anhui, China, and a further 400 MW at Shandong Province. The latter is a mixture of floating PV and PV installed on piles, which is not technically floating.

Out of the 1 GW floating PV tender, 280 MW has been grid-connected by the end of September, and the rest of the projects are still under construction. The 280 MW tranche includes 2 projects from Trina (120+50), 1 project from GCL (60) and 1 project from Linyang (50).

Below is a list of the largest floating PV projects that we are aware of (including the 280 MW mentioned above).

Looking at the pipeline again, how much capacity are we talking about, and where?
China will quickly reach over 1.5 GW of floating PV installed (under the umbrella of two Top Runner Programs, <1.4 GW), and from then will continue growing fast.

The existing market will continue to expand, particularly in Japan and Korea. An additional 13.7 MW built by Kyocera on the Yamakura Dam reservoir in Japan’s Chiba Prefecture is scheduled to be completed in 2018.

Floating PV is more advantageous for use in hot climates, where the benefit of the cooling effect and performance gain is the highest. Hence there is high potential in countries including India, Pakistan (where the IFC is doing a country-level FPV feasibility study as we speak), Thailand, Vietnam, Myanmar, Cambodia, Sri Lanka, Philippines, Taiwan, and Singapore.

We have heard of interest in 100 MW+ projects for several of these countries, but cannot confirm the pipeline at the moment. There is also growing demand for floating PV projects from the EU, U.S., South America (e.g. Brazil), too.

We often hear about the advantages of floating PV on dams and drinking water sources. How much hard data is there about evaporation reduction?
At the moment, we don’t have any hard data on this. This is being evaluated at the Singapore Floating PV testbed, as part of the environmental impact assessment. However, our own results are not yet conclusive.

Floating PV coupled with hydro generation could be very attractive. What is your understanding of these advantages? What kind of potential do you see there?
There are many advantages for combined operation of hydropower stations with floating PV. These include:

• The deployment of PV on existing hydro reservoirs.
• Electrical infrastructure and grid connection already exist in hydropower plants. This can lower the overall capex for installing FPV.
• Usually dry seasons with less water flow correspond to period of high solar insolation and vice versa, thereby reducing the seasonal variations in power production.
• FPV can support day-time peak load and more hydropower is reserved for evening peak.
• Hybrid operation can improve the power quality of FPV power and reduce FPV power curtailment. Instantaneous irradiance variability can be largely compensated by the fast-responding hydro turbines. In turn, this can reduce the system spinning reserve in the grid, thus lowering overall operation cost.

So as you can see, there is great potential for hybrid operation. Due to hybrid operation requirements, the potential for floating PV coupled with hydro is more determined by installed hydro power plant capacity. There is usually sufficient reservoir water surface area.

According to the International Hydropower Association 2017 Hydropower Status Report, only a fraction of these hydro reservoirs would mean FPV coupled with hydro at least to the order of a few hundred GW.

In fact, we think the potential of FPV coupled with hydro is potentially at terawatt scale.