International Solar Innovation Council
Innovating Solar Solutions for Billions
PROJECT DETAILS
Title of the Project: E-rickshaws charging up with solar power
Brief Description
Electric rickshaws, introduced in India in 2008, have revolutionized urban transportation by providing an emissions-free and noiseless mode of travel. These battery-operated vehicles have largely replaced pedal-powered cycle rickshaws in most areas. However, despite their numerous advantages, electric rickshaws suffer from significant drawbacks. They typically rely on lead-acid batteries that take a long time, approximately 9-10 hours, to fully charge and offer a limited mileage of only 85-90 kilometers. This limitation in mileage affects the earnings of rickshaw owners, as more mileage equates to more income. Furthermore, charging the batteries only when they are completely depleted negatively impacts the battery's lifespan. High depth of discharge (DOD) during low voltage conditions significantly shortens the life of these lead-acid batteries, leading to costly replacements, which can cost up to one-fifth of the vehicle's price.
​
To address these challenges and make electric rickshaws both commercially and environmentally viable, the development of a network of solar-powered charging stations is proposed. Most Indian manufacturers offer electric rickshaws with lead-acid batteries that cannot support fast charging. However, a few manufacturers provide rickshaws with lithium-ion battery packs that can be fast-charged, but these models come at a higher cost. The envisioned solar-powered charging stations will feature multiple charging points capable of accommodating both slow charging for lead-acid batteries and fast charging for lithium-ion batteries. Slow charging points will deliver a continuous current of 12A, requiring a 1kW solar power plant to charge one electric rickshaw equipped with a 48V/100Ah lead-acid battery bank in 10 hours. Fast charging points will provide a continuous current of 30A, allowing a 48V/85Ah lithium-ion battery pack to charge in just 3 hours, necessitating a 2kW solar power plant. Excess solar power can be fed back into the grid when not in use, provided there is a grid-connected inverter in place. These fast charging stations promise not only cost savings but also quicker charging times.
​
The objectives of this initiative are threefold: firstly, enabling on-the-road battery charging for electric rickshaws, secondly, extending the mileage and battery lifespan, and finally, reducing battery charging costs. The economic benefits are apparent, with the cost of solar power (EUR 0.025-0.035 per unit) significantly lower than electricity generated from coal-based thermal plants (EUR 0.05-0.1 per unit). With over two million electric rickshaws in operation across India, consuming an average of 10 mega units of electricity daily, transitioning to solar-powered charging stations could lead to a substantial reduction in carbon emissions. The emissions associated with coal-based power plants are substantial, including 9,100 - 9,500 tonnes of CO2 emissions avoided per day. This transition also holds the potential to benefit rural communities, where reliable power supplies can be scarce, offering a sustainable and dependable energy source. In sum, the implementation of solar-powered charging stations holds the promise of transforming electric rickshaws into a more eco-friendly and economically viable mode of transportation across India.
Name of the Principal Investigator: Dr. Joydip Jana
Name of the Co-Principal Investigator: Mr. Abhijit Das
Current Progress in Brief:
The project has advanced significantly, focusing on developing and testing solar-powered charging stations for electric rickshaws. Initial iterations included a 300W charger with DC-DC converter and MPPT function, followed by a 425W version. Now, the project is working on a 525W charger compatible with emerging 700 Wp solar PV modules. Future plans involve a charger with multiple parallel-connected DC-DC converters, ensuring a continuous 30A charging current. These developments underscore the project's commitment to adapting to technological advancements, creating efficient, future-proof charging stations.