The year was 2001 and energy expert Dr Brahmanand wanted to show that even an urban family could adopt sustainable practices.
“People would laugh at me for installing a solar power system in my house, because electricity was comparatively cheap in 2001. They would see it as an unnecessary expense. But I looked at the bigger picture — focusing not on the money spent at that time, but on the energy saved in the long run,” Dr Brahmanand shares.
The two-storey house, built on 1,400 sq ft, has three bedrooms and a living room, all built on the principle of reducing the couple’s carbon footprint.
The living spaces do not have air conditioners; instead, fans and natural airflow keep the house comfortable.
The family started by installing an off-grid solar power system that generated 4.8 kWh of electricity per day, which met the needs of their household of seven.
However, Dr Brahmanand, a visiting faculty member at the Asian Institute of Technology in Bangkok, felt that it was also pertinent to think about the energy efficiency of the appliances being used, which led him to buy only energy-efficient products.
“It is easy to find products with energy consumption ratings today, but back then, I would have to follow up with the companies directly to find the details. Often, those products weren’t available in retail stores. But this holistic approach is important to make sure that the solar power system performs at its best,” he explains.
While a typical urban household in India consumes about 300-600 units of electricity per month, the Mohantys’ electricity bill is zero. They only pay metre charges, as the solar panels generate power even on cloudy days.
When the battery power of the off-grid system started declining, Dr Brahmanand opted for a grid-interactive rooftop solar system.
In a conventional setup, electricity flows from the grid to the household. But in Dr Brahmanand’s bi-directional system, it can flow both ways.