A bird control spike is also known as an anti-roosting spike or roost modification are used on ledges, street lights and commercial signs to prevent birds landing and roosting. The needle-like rods help to deter birds without harming or killing them.
More recently, they have been used around solar panels in an attempt to stop pigeons from nesting underneath. However, unless you were to put them over the entirety of your roof, they are unlikely to make any difference at all.
The pigeons will still find space to land on the tiles and, due to their intelligent nature, they will soon find a way to push their way through the rods unharmed. This means that bird spikes will not stop them from nesting under your panels and unleashing chaos on your roof.