Minimize supply-chain risks: Here’s how India could pursue self-sufficiency in energy storage

At particular risk are battery electric storage systems (BESS) that are now increasingly favoured by renewable energy (RE) producers for grid-scale storage. In his first term as US president, Donald Trump had begun barring China from access to what it deemed vital technology. It shattered the illusion of Big Tech’s offerings being part of the global commons, as it were, open to all for a fee.

When Trump launched his tariff war on the global economy in his second term, China retaliated by curbing access to critical minerals, done by tightening its grip on supply. India was among the importers that suffered collateral damage from this trade tit-for-tat between the two current archrivals for world power.

The Gulf war’s Hormuz crisis that has disrupted hydrocarbon supply this year is just the latest example. Commerce works, but only so long as it works. Extra-commercial considerations could kick in with little notice—and with no provocation by us—to wreak havoc on our vital infrastructure.

Globally, China dominates the field of BESS, whether we go by its technology, production, global market share or supply chains that go all the way back to mines and minerals—from nickel and cobalt to lithium and copper, all vital inputs for batteries.

Some capacity for energy storage is unavoidable in a grid fed by RE, given the variability of its generation and need for grid stability. But we could minimize our reliance on battery storage to what grid stability requires and adopt other means for the rest.

The most conventional option, of course, is pumped storage, in which excess electricity generated is used to pump water up an elevation, from where it can be allowed by a sluice gate to gush down, turn a turbine and generate more power like a hydropower plant does.

Its downside is its project complexity; few locations qualify for water reservoirs along hillsides, given the risks of ecological and social disruption.

Another method is the use of concentrated solar power that can store heat; concave mirrors track the sun through the day, focusing its rays and heat on a container with salt that melts and traps heat. The molten salt can then be pumped through a heat exchanger to turn water into steam that turns a turbine when electricity is needed.

The technology that holds most promise is probably green hydrogen, in which RE is used to split water into hydrogen and oxygen. This hydrogen can be stored, transported and used as fuel in a combined-cycle gas turbine to produce power. In the first cycle, fuel ignites to create a combustive blast that drives a turbine, and in the second, the residual heat creates steam for a steam turbine.

Hydrogen can also be used to generate power in fuel cells, a tech advancement that can run electric vehicles without any need of plug-in batteries. What’s more, hydrogen can take the place of petrol in an internal combustion engine as well, producing water vapour as exhaust rather than carbon dioxide, a climate-distortive gas.

Some of these modes of storage only need cost-value equations to work out, but could potentially help us avoid external dependence. That’s reason enough for a policy push.