Concept development of exercise-to-power: The Green&Healthy power concept

Energy harvesting systems can capture and convert small amounts of energy from various natural sources, contributing to offsetting the growing global energy challenges without incurring the depletion of additional energy resources. Human kinetic energy can be obtained from physical exercise - in indoor cycling, the athlete's metabolic energy converts into heat, enthalpy (to the environment), and work. This study reports on the concept development of the Green&Healthy Power system, an energy harvesting system that collects energy from physical activities. A case study based on an indoor bike generator as a conceptual innovation is presented. The user can select the intensity of effort in which the exercise occurs to produce electricity. Using situations based on literature results, the gains are evaluated by measuring aerobic endurance. The user is informed about the health benefits of the exercise (traditional indices), the energy produced, and the greenhouse gas emissions avoided. This study also reviews some aspects of precedent practices, highlighting the concept's challenging characteristics and setting out the initial formulation of the Green&Healthy Power system. This contribution defines research, development, and demonstration priorities for new ideas and technologies to improve energy efficiency and reduce the final consumption of primary energy. As results of the study case, initial figures indicate that 1000 people performing 20 min of activities on the energy harvesting system three times a week can avoid annual emissions of 180 kg CO₂ and produce 800 kWh/year of electricity, resulting in savings of R$ 800/year. Brazil has a population of 200 million inhabitants and if 1 % of the population carried out this activity, electricity generation could reach up to 1.6 TWh/month (= 19.2 TWh/year), representing 3.4 % of electricity flows within the Brazilian electricity matrix.