The Dawn of 'Two-in-One' Energy Projects
The core idea is simple yet transformative: instead of building a solar farm and separately figuring out storage, new schemes integrate both from the start. This model, often called a hybrid or co-located project, combines renewable energy sources like
solar and wind with an energy storage system (ESS) in a single design. The goal is to provide a consistent power supply, overcoming the natural intermittency of renewables. By storing excess energy generated during sunny or windy periods, these projects can release it during peak demand hours, such as the evening, when solar power is unavailable but electricity usage is high. This turns renewable power from a variable resource into a firm, dispatchable asset that grid operators can rely on.
Why India is Pushing for 'Round-The-Clock' Power
This strategic shift is driven by India's ambitious climate goals and growing energy needs. The country is targeting 500 GW of non-fossil fuel capacity by 2030. As more solar and wind power comes online, it creates a challenge for grid stability. To address this, the government is promoting 'Round-the-Clock' (RTC) power tenders. These are agreements where a power developer commits to supplying a continuous, 24/7 block of electricity from renewable sources. This model is crucial for reducing dependence on coal, especially for meeting the base load—the minimum level of electricity demand over a 24-hour period. It ensures that as India decarbonises, its industries and homes have a reliable and secure power supply.
How It Works: Floating Solar and Big Batteries
A prime example of this integrated approach is the recently approved Pradhan Mantri Surya Sarovar Yojana (PM-SSY). With an outlay of over ₹5,000 crore, this scheme aims to develop 5,000 MW of floating solar projects on existing reservoirs and water bodies, each with a co-located battery energy storage system (BESS). These projects will have at least two hours of storage capacity. During the day, the floating solar panels generate electricity, powering the grid and charging the batteries. In the evening, the batteries discharge, supplying clean power and helping to stabilise the grid. This approach not only provides reliable energy but also saves valuable land resources.
The Key Technologies: Batteries vs. Pumped Hydro
Two main technologies are leading India's storage revolution: Battery Energy Storage Systems (BESS) and Pumped Storage Projects (PSP). BESS, typically using lithium-ion batteries, are modular, quick to deploy, and excellent for responding to rapid grid fluctuations. Their costs have been falling dramatically, making them increasingly competitive. PSPs, on the other hand, are a more established technology. They act like giant water batteries, using surplus electricity to pump water to a higher elevation and then releasing it through turbines to generate power when needed. While PSPs have a longer lifespan and can store massive amounts of energy, they have longer gestation periods and are geographically dependent. India is pursuing both, with policies in place to accelerate the deployment of each technology to meet different grid needs.
Benefits Beyond a Stable Grid
The impact of combining generation and storage extends far beyond grid management. For industries, it means better energy security and lower electricity bills by avoiding high 'peak demand' charges. For the economy, it spurs domestic manufacturing in areas like battery cells, solar modules, and floating solar systems. The PM-SSY scheme alone is expected to create thousands of jobs and reduce carbon emissions by about 10 million tonnes annually. Furthermore, by creating a stable demand for storage, these policies are attracting significant investment and fostering innovation across the entire clean energy value chain.
The Road Ahead: Costs and Challenges
Despite the momentum, challenges remain. The upfront cost of energy storage systems, though falling, is still significant. India is heavily dependent on imports for key components like battery cells, creating supply chain vulnerabilities. Building out large-scale infrastructure, whether BESS or PSP, requires navigating complex regulatory and land acquisition hurdles. However, the government is addressing these issues through policy support, including Viability Gap Funding (VGF) to make projects more financially attractive and a waiver on inter-state transmission charges for storage projects. These incentives are crucial for accelerating adoption and ensuring that project execution keeps pace with ambitious targets.
