Solar panels over fish ponds in China reach industrial scale
China has built more solar power over fish and shrimp ponds than the rest of the world combined, more than 95% of all such systems installed anywhere, according to a global analysis of 2022 data. At the Shilihai plant in Hebei Province, developer Dajin Heavy Industry generates 250 megawatts from 370,000 bifacial panels raised above roughly 353 hectares of aquaculture ponds, power coming from the panels and fish farming continuing in the water underneath. Near Ningbo, Trinasolar built a separate 150 megawatt fishery solar plant with its panels raised 2.5 meters over ponds that farm fish and shrimp together. Ponds carrying solar panels now cover about 15,640 hectares across China, and the same analysis puts the theoretical limit for the country, the most it could build if every suitable pond and tidal flat carried panels, at 240.9 gigawatts, split between 163.9 gigawatts over ponds and 77 gigawatts over tidal flats.
Show the numbers
| Ponds | 163.9 |
| Tidal flats | 77 |
| China total | 240.9 |
What the panels do to the water and the animals below
Independent field research on ponds under a fishery solar plant in southeast coastal China found the panels block 89% to 93% of the sunlight that would otherwise reach the water surface, cutting the light that actually reaches it by 94%. That shade cooled the average water temperature by 1.5 degrees Celsius, slowed wind speed over the pond by 41% to 50%, and cut chlorophyll a, the measure scientists use to track algae, by 72% to 94%. Dissolved oxygen, the gas fish and shrimp need to breathe, rose by 8% to 24% under the panels.
All 4 figures come from one field study of ponds under a fishery solar plant in southeast coastal China, its own measured ranges, not a disagreement between sources.
Show the numbers
| Solar radiation blocked | 89 to 93% |
| Chlorophyll a decrease | 72 to 94% |
| Dissolved oxygen increase | 8 to 24% |
| Wind speed reduction | 41 to 50% |
A separate demonstration site in Yangzhong City, Jiangsu Province, measured the cooling directly at the pond surface and found it faded fast with depth, weaker by 56.9% to 92.1% at 0.75 meters and negligible by 1.5 meters, so the effect sits mostly at the top of the water, where many farmed species actually live. That same site found covered ponds absorb more heat at midday, an average of 67.23 watts per square meter at solar noon, because the panels lower albedo, the share of sunlight the water surface reflects, from 0.101 in open water to 0.082 once covered, a drop of 18.8%.
The benefit is not the same for every pond
A global analysis of fishery solar projects found the outcome for the animals living underneath depends on which species is being farmed, how densely the pond is stocked, whether the water is aerated, and how good the water quality already was before the panels went up. Documented pilot projects show aquaculture yield rising by an average of 10.7% once panels go in, and a scenario where panels cover 10% of suitable ponds and tidal flats worldwide could add 856.4 gigawatts of capacity and 750 million dollars a year in extra aquaculture revenue. Reading that analysis directly also turns up a risk that project announcements do not mention, the same reflective panel arrays that cool a pond can look like open water to some birds from above, raising the risk of a collision, the authors of the paper state directly. The paper is also plain that only a limited number of large scale projects have actually been built, so long running evidence for how fish and shrimp fare under the panels stays thin against how fast the practice is scaling.