At some places, electricity does now show up for days, making lives difficult at home and disrupting industries and farming, where irrigation pumps stand idle.
The country's power system is almost entirely dependent on fast depleting fossil-fuel, with state-owned and private sector power plants only able to generate up to 3,800 megawatts of electricity a day against a demand of 5,500 megawatts.
All of this makes solar energy systems, offered to villagers heavily subsidized by the World Bank and via an installment scheme run by the state-owned Infrastructure and Development Company Limited (IDCOL), a big relief.
"Life has become much easier now," said Kulsum Begum, a mother of four whose husband and son work abroad and who lives in Pritomoddi, some 60 km (40 miles) southeast of the capital Dhaka.
Begum installed a 40-watt solar system on the roof of her house, which powers four bulbs, one television and also recharges her lifeline: her mobile phone.
"Whenever I need something, I call my husband or son on the cellphone. I am so happy now," she said.
The price of a solar system ranges from 9,500 taka ($135) to 68,000 taka ($970) depending on capacity but the villagers usually pay in installments. Prices are also set to fall after the government lifted import duties on solar panels last month.
Grameen Shakti, a non-profit organization linked to the Nobel Prize winning micro credit agency Grameen Bank, pioneered home solar systems and works with the World Bank and IDCOL to spread the technology throughout the impoverished country.
"Literally 80 to 85 million Bangladeshis are not getting any electricity. So we are extracting sunshine and producing green energy at the grassroots level," said Dipal Chandra Barua, managing director of Grameen Shakti.
"Right now 2.5 million people are benefiting from solar energy and we have a plan to reach 10 million people by the end of 2012," said Barua, who recently won the $1.5 million Zayed Future Energy Prize from Abu Dhabi for his contribution to renewable energy technology.
Since June, Grameen Shakti has installed more than 250,000 solar home systems, accounting for some 66 per cent of the total of solar-powered households. Barua said around 10,000 new solar home systems are being fitted every month.
In Pritomoddi, televisions and mobile phones, which not long so ago were unattainable luxuries, have become common as most villagers enjoy uninterrupted power.
Businesses are also booming.
"Now I keep my shop open hours after the sun had gone down. I get bright light from the solar system instead of the dim glow of kerosene-fired lanterns. It cut my cost, attracts customers and has pushed my business up," said tailor Akthar Hossain.
"Previously when I did not have the solar, I had to pull down shutters early, and had to be content with less than 500 taka ($7) daily. Now I earn more than 800 taka ($12) a day."