By Isha Lodhi
A Project by Umair Shafi, Salman Javed and Salman Khalid BEE – 2
Load shedding and the increasing price of electricity means that the National Grid is no longer a reliable and cheap source of power. Frequent power shut downs are bad for business, industry as well as agriculture. A group of students from School of Electrical Engineering and Computer Science, NUST, thought of something which could help reduce the load on the national power grid and at the same time reduce dependency on non-renewable energy sources.
What they did was integrate a solar battery charger to a water pump (for irrigating fields). However, it is not as simple as it sounds. Their idea’s uniqueness was to design an MPPT (Maximum Power Point Tracking) charge controller to optimize the battery charging operation from solar panels. When the voltage from the photovoltaic cells exceeds 12 V (which is the battery’s charging capacity), the excess power is converted to current. This is what makes this charger 18-20% more resourceful than PWM charge controllers.
The battery then drives the water pump through an inverter.
The students’ project is a prototype for a possible market product targeting farmers who power their tube wells from expensive electricity bought from unreliable AC mains. They hope that their innovation will eventually replace conventional irrigation systems in Pakistan.