Humanpowered

Humanpowered refers to devices, systems, or activities powered by human body energy, typically through muscle work such as pedaling, pushing, pulling, rowing, or lifting, without the use of external motors or combustion engines. In practice this energy is converted by the body into mechanical work and sometimes stored in mechanisms such as flywheels or batteries for later use. Metabolic efficiency in humans is variable but generally around 15-25% for sustained tasks, with higher peak efficiencies possible in trained individuals. Mechanical systems using human power can include bicycles, hand cranks, pedals feeding a generator, and oars on boats.

Applications are broad: transportation (bicycles, tricycles, unicycles, pedal-powered cargo bikes), recreation and exercise equipment (rowing machines, stationary bikes), and manual agriculture or water-pumping tools (hand pumps, pedal-powered irrigation pumps, threshers). In humanitarian and developing-world contexts, pedal-powered devices can reduce reliance on fuel and extend access to water, irrigation, and milling.

Advantages include low operating costs, zero emissions at point of use, health benefits from physical activity, and simplicity. Limitations include limited power output relative to motorized systems, dependence on user capability and endurance, slower pace for heavy loads, and potential ergonomic or safety issues. The concept is often contrasted with human-assisted or motorized systems, and has a niche role in sustainable transport and appropriate technology movements.