poCYDES is a compact, bicycle-powered reverse osmosis system designed to provide high-quality drinking water from seawater, brackish, or contaminated sources in remote and disaster-stricken areas. By utilizing an innovative piston pump with integrated pressure energy recovery, the unit achieves the required pressure levels for desalination while drastically reducing the physical effort needed, allowing a single user to meet the daily water needs of an entire family through pure muscle power. The system is mounted on or towed by a standard bicycle that remains fully functional, offering a mobile, low-maintenance, and power-independent solution where industrial infrastructure is unavailable. This robust technology bridges the gap between large-scale industrial plants and the urgent need for affordable, decentralized access to safe drinking water.