Biological photovoltaic cell (IMAGE) University of Cambridge Caption This system, containing blue-green algae, powered a microprocessor continuously for a year using nothing but ambient light and water. Credit Paolo Bombelli Usage Restrictions With credit License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.