Current Affairs for 17 June 2026

Sitapur Solar Project: India's First Defence Solar-BESS Project

Why in News ?

• Defence Minister Rajnath Singh has approved a 250 MW Solar Power Project with an integrated Battery Energy Storage System (BESS) at Sitapur, Uttar Pradesh.
• The project will be developed on approximately 850 acres of vacant defence land, making it India's first large-scale solar project on defence land.
• It is the first Ministry of Defence initiative to combine solar power generation with Battery Energy Storage System (BESS), aimed at enhancing energy security for the Armed Forces and promoting green defence infrastructure.

What Makes the Sitapur Solar Project Unique ?

The Sitapur Solar Project is a landmark initiative that brings together renewable energy, energy storage, and defence infrastructure for the first time in India. Developed on around 850 acres of vacant defence land in Uttar Pradesh, the project is expected to become a model for future green energy projects across defence establishments. It reflects India's efforts to strengthen energy security while promoting sustainable development.

First Large-Scale Solar Project on Defence Land

One of the most significant features of the project is that it is India's first large-scale solar power project to be built on defence land. Instead of leaving large areas of land unused, the Ministry of Defence is utilizing them to generate clean electricity. This not only reduces the need for acquiring new land but also demonstrates how government-owned assets can be used efficiently to support national development and environmental sustainability.

First Ministry of Defence Project with BESS

The Sitapur project is also the first initiative of the Ministry of Defence to combine solar power generation with a Battery Energy Storage System (BESS). Since solar energy is available only during daylight hours, the battery system will store excess electricity generated during the day and supply it whenever needed. This will help ensure a stable and uninterrupted power supply while maximizing the use of renewable energy.

Strengthening Defence Energy Security

Reliable electricity is essential for modern defence operations. Military facilities depend on continuous power for communication systems, surveillance networks, command centres, and radar installations. The integrated battery storage system will provide backup power during grid failures, natural disasters, emergencies, or periods of high demand. As a result, the project will strengthen India's energy resilience and improve the operational readiness of the armed forces.

Supporting India's Green Defence Vision

The project is an important step towards building greener and more sustainable defence infrastructure. By increasing the use of solar energy, it will help reduce carbon emissions and decrease dependence on conventional sources of electricity. It also aligns with India's broader goals of expanding renewable energy capacity and achieving long-term energy security.

What is a Battery Energy Storage System (BESS) ?

A Battery Energy Storage System (BESS) is a technology that stores electricity for future use. It captures surplus energy generated from renewable sources such as solar and wind power and releases it when required. In simple terms, it works like a giant rechargeable battery that helps ensure a continuous and reliable power supply.

How Does BESS Work ?

The working of BESS is simple. During the day, solar panels generate electricity. Any excess power that is not immediately consumed is stored in batteries. Later, when solar generation decreases, electricity demand increases, or the grid faces disruptions, the stored energy is released. This ensures that electricity remains available even when renewable energy production fluctuates.

Why is BESS Important ?

As the share of renewable energy grows, energy storage is becoming increasingly important. Solar power is available only when the sun shines, while wind energy depends on weather conditions. However, electricity demand continues throughout the day and night. BESS helps bridge this gap by storing excess energy and supplying it whenever required. This improves grid stability, reduces energy wastage, enhances energy security, and supports greater use of clean energy.

Major Energy Storage Technologies

Besides BESS, several other technologies are used to store energy. Pumped Hydro Storage (PHS) stores energy by pumping water to a higher reservoir and releasing it through turbines when electricity is needed. Compressed Air Energy Storage (CAES) stores energy in the form of compressed air, which is later used to generate electricity. Flywheel Energy Storage stores energy as kinetic energy in a rapidly spinning wheel, while Gravity Energy Storage generates power by lowering heavy masses that were previously lifted using surplus electricity. Together, these technologies play a crucial role in ensuring reliable power supply and supporting the transition towards a cleaner and more sustainable energy future.

Key Takeaway

The Sitapur Solar Project is not merely a renewable energy project. It represents the convergence of national security, clean energy transition, energy storage technology, and efficient utilization of public assets, making it a significant milestone in India's journey toward sustainable and self-reliant defence infrastructure.

GRAPES-3 Telescope: New Discoveries on Cosmic Rays and Muons

Why in the news ?

Recently, researchers from Mumbai, Kochi, and Japan used the GRAPES-3 (Gamma Ray Astronomy PeV Energies Phase-3) telescope to study how the temperature of Earth's upper atmosphere and the Sun's magnetic field affect muons, subatomic particles arriving from space.

What is the GRAPES-3 Telescope ?

• GRAPES-3 is an advanced astronomical observatory developed to study the origin, acceleration, and propagation of cosmic rays.

Key Features

• Full name: Gamma Ray Astronomy PeV Energies Phase-3 (GRAPES-3)
• It studies high-energy cosmic rays and gamma rays entering the Earth's atmosphere.
• It also analyzes solar activity and geomagnetic storms through cosmic ray muons.
• It is equipped with an array of plastic scintillator detectors and a large-area muon detector.
• Location: Ooty (Tamil Nadu)
• Operation: Tata Institute of Fundamental Research

What are muons ?

• Muons are subatomic particles similar to electrons but with greater mass.
• They are produced when cosmic rays collide with Earth's atmosphere.
• Muons can travel at nearly the speed of light and reach Earth's surface.

What are cosmic rays ?

• Cosmic rays are highly energetic charged particles that travel towards Earth from outer space.

Key Facts

• They were discovered more than 100 years ago.
• They are considered among the most energetic particles in the universe.
• They enter Earth's atmosphere and produce a particle shower.
• This shower includes particles such as electrons, photons, protons, neutrons, and muons.
• Their energy range is approximately 10⁸ eV to 10²⁰ eV.
• They reach Earth continuously from almost all directions.

Significance of the Study

• Helps understand the relationship between Earth's atmosphere and space weather.
• Improves assessment of the impacts of solar activity on Earth.
• Contributes to understanding the nature of cosmic rays and cosmic phenomena.
• Provides a vital research base in the fields of space science and astrophysics.

Conclusion

The GRAPES-3 telescope is an important astronomical research project in India, playing a key role in the study of cosmic rays, muons, and space weather phenomena. This helps to better understand cosmic processes, solar activity, and their impacts on Earth's atmosphere.