Jellyfish numbers are rising and that's bad for coal, nuclear plants

Jellyfish population may be on the rise and that is a concern for coastal coal and nuclear power plants that rely on seawater.

Last year the United Nations warned that jellyfish populations were on the rise. A University of British Columbia study cautiously stated that jellyfish populations seem appear to be climbing. Lead author Lucas Brotz found that out of 66 large marine ecosystems studied, 45 showed an increasing trend in jellyfish population.

Large jellyfish blooms have shut down power plants.

Last year the Oskarshamn nuclear plant in southeastern Sweden had to cope with a jellyfish bloom that clogged the intake pipes.

Three years ago a surge in jellyfish shut down the Orot Rabin coal-fired power plant in Hadera, Israel after jellyfish blocked the seawater supply. Coincidentally the Torness nuclear power station in Scotland also closed after jellyfish were also found to be obstructing water filters.

Jellyfish haven't just caused problems with cooling systems for power plants. In October stinger jellyfish caused $2 million in damage to salmon farms in Ireland.

Reasons for the increase are unclear. Possible causes are a warming climate. As the oceans become more acidic, jellyfish can do better. There is also loss of jellyfish predators due to over-fishing.

However, help may be on the way: a robotic jellyfish terminator has been developed by Korean engineers. The KAIST Civil and Environmental Engineering Department unveiled last year the unmanned aquatic robots capture and grind the jellyfish. A formation of three robots can wipe about about 900kg of jellyfish per hour.

Video of the device in action below.

Jellyfish warning sign by Nelo Hotsuma