May 11, 2018-The Nepal Electricity Authority (NEA) is mulling to install a battery storage system to store electricity during off-peak hours and supply it during peak hours.
The technology uses high capacity lithium batteries to store electricity generated by different types of power plants when demand is low, and feeds it back to the grid when production falls below demand. The battery storage system is installed in the substation.
The state-owned power utility said it was preparing to call global tenders to procure such batteries. “We are currently preparing the bid documents with technical help from the Asian Development Bank (ADB),” said Kulman Ghising, managing director of the NEA. “We will initiate the public procurement process as soon as the bid documents are finalized.”
Once a supplier is selected through global bidding, it will not take much time to install such a battery storage system, according to the NEA. The NEA said that the storage system would be ready before the next dry season when it is difficult to meet peak demand.
The power utility is planning to install a storage system with a capacity to store up to 100 MW of electricity at two locations initially as a trial. “If the system works well, we will increase the capacity,” said Ghising.
A majority of the hydropower projects in the country are of the run-of-the-river type, and their production remains constant round the clock. Demand for electricity is high during the day and in the evenings, but production exceeds consumption during the night.
“During peak hours, our supply is not enough to meet demand while during off-peak hours like at night, supply is higher than demand and the surplus energy is going to waste,” said Ghising. “If we can store the surplus energy, it can be supplied to industries and households during peak hours when demand is high.”
The battery storage system is one of the two solutions that the NEA is considering to balance demand and supply. The second option is ‘power banking’ with India.
It has already shared a concept note regarding power banking with Indian authorities.
Power banking refers to exchange of electricity for electricity instead of cash. It is a mechanism under which one country exports electricity to the other when there is surplus energy and imports back the same quantity of energy when there is a deficit. If the southern neighbour agrees to the power swap arrangement, Nepal can export surplus electricity to India when demand is low and import back the same volume of power when demand is high.
Nepal is keen to barter energy as the price of electricity is lower in India. Against this scenario, power banking could be an ideal way to manage surplus energy, officials said.
Source: The Kathmandu Post