Heat Generation and Thermal Response of Enclosed Batteries/Electronics in Autonomous Street Lighting Applications

Renewable energy, solar and wind, are now being used in off-grid street lighting applications, like to ones manufactured and sold by PoleCo limited. Such systems are installed in regions where the electrical grid is absent and where there is enough solar (or wind) resources to charge lead-acid batteries, and power the lamp for daily usage. Focusing on areas of high solar resources, where a set of batteries is charged during the day from a solar photovoltaic panel, and discharged at night while providing power to the street lamp; the system is faced with the unfortunate consequence of high solar irradiance and high surrounding temperatures. This leads to an increase operating temperature of the batteries and control electronics which results in a drastic decrease in their lifetime as well as possible catastrophic failures by thermal runaway. This research project will experimentally study the thermal behaviour of the lead-acid batteries used by PoleCo in order to develop a validated numerical model of the batteries/control electronics/enclosure used in their streetlight applications. With such model, various scenarios will be studied by numerically varying environmental conditions (solar irradiation, outside temperature, wind factor) in order to determine the thermal transient behaviour of the system. Ultimately, possible designs leading to better thermal management will be numerically studied, with the most promising ones leading to implementation by PoleCo. The better management of the batteries and electronics from a thermal point of view will result in the prolonged life of the equipment, reducing the operating cost of the systems and providing PoleCo with an increase market share, revenue and growth of the company, benefiting the Canadian economy.