This underwater robot cleans ships to cut emissions and protect marine ecosystems Imagine a ship making its way across the ocean. It might look elegant as it cuts serenely through the waves. But a look below the water reveals a different picture, with countless aquatic species like barnacles covering the craft’s hull. It’s been estimated that severe underwater biofouling – as this accumulation of drag-inducing marine life is known – can increase a ship’s fuel consumption by up to 40%, boosting already high CO2 emissions. More than 4,000 marine species have been identified as biofouling organisms. Maritime transport emits around 940 million tonnes of CO2 annually and is responsible for about 2.5% of global greenhouse gas emissions. It’s been estimated that if global shipping were a country, it would be the sixth biggest polluter, generating more emissions than Germany.