Solar power plant owners are resorting to sophisticated bird deterrence systems in a bid to eliminate soiling problems on projects on or near water. The use of laser systems, for example, has in some cases helped bring about a 75% reduction in birds whose droppings can cause up to a 30% loss of production, according to anecdotal reports from project owners.
This can increase the payback time of the project by up to five years, according to Bird Control Group. The company sells a system, called Agrilaser Autonomic, that scares birds around the clock by moving a harmless laser beam over an area of up to 500 acres.
Unlike other bird-repelling systems, such as kites or recorded alarm calls, the laser system seems immune to habituation. Systems installed by Bird Control Group three years ago continue to scare off birds today, the company says. Bird droppings can be a major problem for floating PV systems and those in areas where larger avian species feed or rest.
Gulls and geese, for example, may use floating structures as roosting sites, leaving guano that damages the surface of PV panels and is hard to wash off. An Agrilaser Autonomic was installed at the world’s third-largest floating solar array, on the Queen Elizabeth II Reservoir in Surry, UK, to keep a population of more than 10,000 black-headed gulls from using the plant as a roosting site.
And at Sheeplands Farm, a UK floating solar plant equipped with Ciel & Terre’s Hydrelio PV systems, electricity production soared by up to 20% after lasers were deployed. “The Agrilaser Autonomic could be the best innovative product in the world for bird repellent,” said asset owner Mark Bennett, who had previously tried kites and acoustic devices to scare off gulls and ducks roosting on the plant.
A further benefit of the system is that it reduces the frequency with which solar plants must be cleaned, cutting operations and maintenance costs. The Agrilaser Autonomic costs around €7,000 per unit, with up to a further €1,000 for installation in markets where Delft, Netherlands-based Bird Control Group has a reseller. Once set up, though, running costs for the system are minimal.
It operates automatically, with no need for human intervention, and can be powered either from a grid connection or via an additional solar charging system. The laser works as a deterrent for most marine and water-based bird species. Only birds of prey, which do not have natural predators, are immune to the system. However, given their scarcity these species rarely represent a problem in terms of soiling.
“We have studied the behaviour of birds and discovered it is possible to introduce a new artificial enemy using laser technology. An approaching laser beam appeals to the survival instinct of birds, making them take evasive action.”
The advent of bird-repelling technologies on solar plants is relatively recent, but the technology used by Bird Control Group is already widely employed in industries including agriculture, aviation, fishing, oil and gas, real estate and recreation. In solar, its use is likely to increase along with a growing trend towards floating plants. As previously reported in Solarplaza, there are already more than 90 MW of floating PV worldwide, spread across at least 70 plants.
The plants are favoured in markets such as Japan because they help preserve land for other uses, reduce freshwater evaporation and operate at high efficiency because of the cooling effect of the water. The latter can help improve annual generation by between 5% and 20%, depending on climate, according to floating plant developer Ciel & Terre.
Most floating plants tend to be under 1 MW in size, which means they can easily be covered by a single Agrilaser Autonomic unit. For very large plants, though, it is easy to install and operate multiple laser systems. “We have spent years of research on developing the ultimate laser system for bird control use,” said Steinar Henskes, Bird Control Group’s founder and CEO.
“We have studied the behaviour of birds and discovered it is possible to introduce a new artificial enemy using laser technology. An approaching laser beam appeals to the survival instinct of birds, making them take evasive action.”
The system is harmless not only to birds but also to other animals and to humans. Furthermore, it is silent and therefore practically unnoticeable to people in neighbouring communities. Plus it can be deployed on a variety of sites, from commercial and industrial rooftops to standard utility-scale plants.
“Whatever the size of the plant, effective bird control reduces the need for maintenance and cleaning, improving energy input,” Henskes said. “This system helps protect production without causing harm to the environment.”
