Floating PV

Floating PV is a plant type where the PV array sits on a floating structure on a body of water instead of on land or a roof. An onshore floating plant has four main parts: a floating structure for buoyancy, an anchoring and mooring system that holds it in place, the PV modules, and the electrical balance of system, which covers DC and AC cables, inverters, transformers, monitoring and earthing. Floating structures on the market range from pure HDPE floats to rafted HDPE and steel systems and ring-shaped membranes, and anchors can be placed onshore, near the shore or on the reservoir bottom. The modules are usually like those used on ground-mounted plants, but glass-glass modules are generally recommended because they resist moisture and water ingress better. Onshore (inland) floating PV is built on inland water bodies such as gravel extraction ponds, hydro and pumped storage reservoirs, flooded quarries, fishponds and water treatment plants, while marine floating PV is built for salty or brackish water, nearshore or offshore. Offshore floating PV covers any site in unsheltered water, where significant wave heights exceed 2 to 3 m. Its benefits include less pressure on land use, less water evaporation, and a water-cooling effect that can give higher efficiency than ground-mounted systems, although the tilt angle has to be taken into account when comparing the two. Floating PV can share grid connections with hydroelectric dams, wind plants and storage, but sites may need an environmental impact assessment and permits under national and regional rules.

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• sentence 1: support check: partial - Passages describe floating PV on water bodies with floating structures, but no explicit definition contrasting it with land or roof installations.
• sentence 5: support check: partial - Onshore is defined as any inland water body and marine as salty or brackish water, nearshore or offshore; the listed examples come from the passage list, though the list is of areas for floating PV, not explicitly onshore, and the list's start is truncated. -->