By Rathin Kukreja
On a hot summer afternoon in India, solar panels are working at full capacity. Power is abundant. But just a few hours later, when the sun sets and demand rises, the system quietly turns back to coal.
That contrast captures the paradox of solar energy today. In conversations with utilities over the past year, this exact gap—plenty of solar by day, shortages by evening—comes up repeatedly.
India is producing more clean energy than ever before—but not always when it is needed most. If solar energy is to truly cool the planet, we must not just generate more of it, we must learn to use it better. And in a country that still depends heavily on imported fuels, every unit of wasted solar is not just an environmental loss, it is an economic one.
India’s solar journey has been remarkable. Installed solar capacity has crossed 150 GW, placing the country among the world’s largest solar markets. Costs have fallen sharply, and solar energy is now among the cheapest sources of new electricity.
That said, there is still a gap.
Solar power is available during the day, but demand peaks in the evening—when homes switch on lights, fans, and cooling appliances. Without the ability to store or shift this energy, the system falls back on fossil fuels. Coal still accounts for around 70% of India’s electricity generation, reminding us that capacity alone does not equal impact.
The strain is already visible. In renewable-rich states such as Rajasthan and Tamil Nadu, clean power is sometimes curtailed because the grid cannot absorb it. Recent Grid India data shows that, in April 2026, India curtailed an average of 23 GWh of solar power every day—enough to power one-fourth of Delhi for a day. In total, 693.81 GWh of solar was curtailed that month—74% higher than the combined curtailment in January, February, and March.
This is not just inefficiency—it is lost value. Clean, low-cost electricity is being generated but not used. And in its place, more expensive and polluting fuels continue to fill the gap. Every unit of wasted solar is effectively replaced by other energy sources, imports that India could have avoided.
In simple terms, India is adding solar faster than it is building the infrastructure needed to use it fully. Most utilities will recognize this immediately.
So what actually needs to change?
The most immediate priority is energy storage. Batteries allow excess daytime solar to be stored and used during evening peaks, reducing dependence on coal. They also help stabilize supply when generation fluctuates. Importantly, storage is no longer prohibitively expensive. According to the International Energy Agency, lithium-ion battery prices have fallen from about USD 1,400 per kWh in 2010 to around USD 140 per kWh in 2023, with further declines since. Storage is no longer a distant solution—it is becoming essential.
Alongside this, transmission infrastructure must keep pace. India’s best solar resources are often far from demand centres. Without adequate transmission, clean energy simply cannot reach where it is needed. Faster expansion of inter-state and intra-state networks is critical to reduce bottlenecks and avoid curtailment. Lack of adequate transmission infrastructure is one of the most important reasons for power curtailment.
Equally important is digitalisation moving from the background to the core. As renewable energy scales, utilities need better visibility and control. Today, nearly 15% of electricity in India is lost before it reaches consumers—and in some states, the losses are even higher. This makes it harder to plan, forecast, and integrate renewable energy efficiently.
Digital tools can change this. Smart meters and modern grid systems help utilities understand where losses occur, improve forecasting, and better match supply with demand. India’s push to deploy around 250 million smart meters under RDSS (Revamped Distribution Sector Scheme) is a step in this direction—early results from some states already show how better data improves day-to-day grid decisions.
And underpinning all of this is financing and flexibility. Modern grids require large investments, and lowering the cost of capital is key to scaling solutions like storage. At the same time, flexibility—through storage and smarter demand needs to move beyond pilots and into mainstream deployment. Evidence suggests that such flexibility can reduce overall system costs while allowing more renewables to come in.
India’s renewable expansion has largely followed a capacity-first model—prioritizing rapid solar deployment, with system integration lagging behind. That approach made sense a decade ago. Today, it risks becoming the biggest bottleneck to the next phase of the transition.
A system that cannot fully use clean energy will continue to depend on fossil fuels. As solar grows without matching investments in storage and grid readiness, curtailment will increase—reducing both climate impact and economic returns.
Put simply, solar without supporting systems cannot scale beyond a point.
Nature offers a simple lesson. Natural systems are built on balance and storage, something we often take for granted. A tree does not rely only on the sunlight available at a given moment—it stores energy and uses it when needed. Nothing is wasted.
This year’s World Environment Day theme— “Inspired by Nature. For Climate. For Our Future”—captures this idea well. Sustainability is not just about producing more energy, but about using it wisely.
With hundreds of gigawatts of additional clean energy planned over the next decade, getting this right is no longer optional—it is essential. India now has an opportunity to lead—not just by building more solar, but by making sure that what it generates is actually used.
Because the question is no longer how much solar we can build. It is whether we know how to use it.
