Pankaj Sharma, co-founder of Log9 Materials, says with renewables such as solar and wind, it sometimes does not matter how much capacity has been installed. “If it is a very clear, open sky with no clouds, at 12 o’clock in the afternoon, you will get peak production of energy from solar panels. But on another day, if it is very cloudy, if it is very smoggy, suddenly the same solar panels will produce less. Solar rays are also sometimes high, sometimes low, depending on whether it is 12 o’clock or 2 in the afternoon. By 3 or 4 o’clock, the energy is less,” he says during an interaction with ET Digital.
The situation with wind energy is similar as energy can be generated only when there is sufficient and steady breeze. It is difficult to predict the production of energy in renewables and so plugging them into the grid has always been a challenge, says the co-founder of Log9 Materials, which makes energy storage systems.
A way to store this energy is to connect the renewable energy generating system to a large-scale battery storage system. This will ensure the energy being generated is stored, so that there is a steady supply of power when needed.
“Whenever you need the energy, you can drain the battery out at a very constant rate. So, a battery storage system actually holds the key to making renewables more stable for the electricity grid. Most renewables generate energy in the daytime, but your peak demand of electricity is between 6 pm and 9 pm. Hence, you can take the energy out of the battery at that time,” he says.
Ankit Mittal, CEO of Delhi-based energy storage firm Sheru, says energy storage is a requirement to smoothen out this imbalance. “Without storage solutions, there will be a point where we cannot add further renewable energy onto the power grid without experiencing stability risks. For India to clean up its power grid with cheap renewable energy, storage is essential.” Even though the cost of batteries has declined in recent years, it is still quite expensive, he says. Renewables combined with storage have reached cost parity with fossil fuels in some parts of the world, but not in India. India’s recent announcement of viability gap funding (VGF) is to, among others, increase the uptake of storage solutions.“However, there are innovative technologies such as vehicle-to-grid (V2G) which uses the battery in an EV as a storage device and can be used to reduce the cost of storage. We are also working on creating an energy storage network by aggregating EV battery capacity and reducing the cost of storage through better utilisation,” he says.
These batteries can be expensive. But Sharma says they can also last a long time and the low cost of operations can make up for the high purchase price.
Talking about the limitations of this technology, Sheru’s Mittal says utilisation is an issue. “For intra-day energy storage purposes, the requirement of storage solutions is for not more than a few hours every day. This means that standalone storage applications have utilisation factors of 20% or even lesser, which severely reduces the viability of these projects.”
Sharma says one of the biggest challenges they face is being a first mover of this technology in India as they have to design everything from the ground up.
Another challenge he mentioned is that many battery subsystems in use are not compatible with the renewable energy storage system. “So it required us to spend a lot more capital in our basic R&D to create the systems. The good news is that by now we have built all the other subcomponents. Initially, it was difficult. But now I think it will get easier because now we have all the subsystems, and we have localised Indian vendors who can now manufacture those subsystems for us,” he adds.
