The government has planned to set up 50 solar mini-grids in remote off-grid areas of the country, mainly in islands, by 2018.

Of the planned mini-grids, seven have already been installed while 11 are under the installation process, and the remaining 32 are at the planning stage, according to official sources.

"Each of the mini-grids will have 100-250 kilowatt load capacity for serving 500-1,200 households and commercial consumers," said Enamul Karim Pavel, head of Renewable Energy of IDCOL, a state-owned financing agency.

All these mini-grids are being set up by private sector partner organisations (PO) of the IDCOL, each requiring an investment of Tk 4 - Tk 9 crore depending on the size and capacity.

A solar mini-grid plant means there will be an integrated solar system containing a battery storage system alongside a backup by diesel-fired generator. Initially, electricity will be generated from a solar hub and then it will go to consumers through a distribution lines during the daytime. The battery system will work as power storage to supply electricity during the night time. During any rainy day, diesel-fired generators will provide the backup support.

Officials said consumers can use the electricity for any as usual purposes like household lighting, running fans or small industrial or irrigation motors. Even refrigerators and microwave ovens could be run with power from a solar mini-grid.

"We have mainly chosen the remote islands for the solar mini-grid projects as those are located far away from the national grid system. Even, there is hardly any possibility for these areas to get grid-connected electricity in future," said Siddique Zobair, member of the Sustainable and Renewable Energy Development Authority (Sreda).

Sreda, which was created about two years back for the promotion of renewable energy in the country, has been providing policy support to the solar mini-grid projects with IDCOL financing them.

The seven mini-grids, established with IDCOL financing in the remote islands, are in Swandip and Kutubdia in Chittagong, Monpura in Bhola and Raipura in Narsingdi, and two islands in Rajshahi and one in Kurigram district.

Zobair said solar mini-grid electricity is better than solar home system because consumers can use it like conventional electricity, and it has no time limitations like those in home solar system.

Enamul Karim said the tariff of each unit of solar mini-grid electricity is about Tk 20. But, the use of energy efficient bulbs, fans and other appliances bring down the cost to an affordable level.

In that case, he said, a household consumer has to pay Tk 400-450 a month for using solar mini-grid electricity while a small factory owner needs to pay Tk 1,500 a month.