When I walk into my garden, yellow faces stare menacingly at me from an air vent in the garage wall. Like tiny fierce aliens ready to attack. But what are they?

I typed ‘wasps with yellow bums’ into Google and soon found the answer. These are Oriental Hornets. And they have a special talent – they are solar-powered.

Oriental Hornets are about 3cm long and found throughout South-West Asia, the Middle-East and Southern Europe. Their brown bodies are able to trap sunlight and the yellow pigmentation on their faces and backs turns the sunlight into electricity. It is thought that this electrical energy is then used for metabolic functions, to keep them at a comfortable temperature and to give them extra bursts of energy when needed.

Oriental Hornets live in colonies ruled by a Queen. The colonies have a caste system – there are the female workers and the male drones. The male drones are used for reproduction and die off shortly afterwards. The female workers maintain the colony and are responsible for different tasks – building the shelter, defending the nest, finding food and looking after the young.

The hornets can give a nasty sting and they weren’t keen on me or my camera and tripod.  After chasing me away a few times, they settled down and I got to see the foragers bringing back food for the colony – one brought an insect bigger than itself. I heard them polishing off a cockroach, leaving just the legs.

They’re a bit scary, but what a work ethic! And to think, humans have only recently managed to use solar power – these hornets have been doing it for thousands of years.