RuKart Technology is at the forefront of sustainable climate solutions, developing innovative technologies to support farmers and rural communities. One of its key innovations, the Subjee Cooler, is an electricity-free cooling device that keeps vegetables fresh for 7-9 days using only water. Deployed across Bihar, Odisha, and Maharashtra, this device proved invaluable during the lockdown, helping farmers secure better prices for their produce.

The Vision Behind RuKart Technologies

RuKart Technologies was founded in May 2019 by Vikash Jha and his IIT Bombay collegemate, Sharayu Kulkarni. Bootstrapping the venture, they focused on creating sustainable agricultural solutions. Their flagship innovation, the Subjee Cooler, is an affordable, electricity-free green storage solution that preserves vegetables using just 20 liters of water per day—without relying on solar power or diesel. It has already been successfully installed in Singanapalli village, Kuppam, Andhra Pradesh.

“In the last 40 months, we have sold over 900 Subjee Coolers across 10 states, empowering farmers with cost-effective, sustainable storage solutions,” says Sharayu Kulkarni, co-founder of RuKart.

Subjee Cooler: Sustainable Cooling Without External Energy

Launched by the Honble Chief Minister of Andhra Pradesh, the Subjee Cooler offers a unique, electricity-free refrigeration solution. Unlike conventional refrigeration systems, which depend on electricity, the Subjee Cooler leverages enhanced evaporative cooling to maintain a lower temperature, extending the shelf life of fresh produce.

How It Works: The Science of Evaporative Cooling

The Subjee Cooler operates on the natural principle of evaporative cooling. Heres how it works efficiently:

1. Porous Material Structure – The cooler is made of double-layered clay or other porous materials that absorb water between the layers.
2. Evaporation Process – As water from the outer layer evaporates into the surrounding air, it draws heat away from the inner chamber.
3. Temperature Drop – This continuous heat removal process lowers the internal temperature, creating a cool and humid environment ideal for preserving perishable goods.
4. No External Energy Needed – Since evaporation occurs naturally, the Subjee Cooler requires no electricity or fuel, making it a sustainable and cost-effective solution for rural communities and off-grid areas.

The Environmental Impact

One of the biggest advantages of the Subjee Cooler is its zero-energy operation, which significantly reduces carbon emissions compared to traditional cold storage solutions.

“Electric cold storage units depend on grid electricity, often generated from fossil fuels, emitting hundreds of kilograms of CO₂ per year per unit. In contrast, the Subjee Cooler is a zero-emission solution that relies entirely on natural evaporative cooling,” explains co-founder Sharayu Kulkarni.

Real Impact: How the Subjee Cooler Helps the Planet

Replacing conventional cold storage methods with the Subjee Cooler can drastically reduce carbon emissions, lower operational costs, and promote self-sufficient food storage systems.

For example, if a small farm replaces an electric cold storage unit (which consumes 1,500 kWh per year) with a Subjee Cooler, it prevents the release of nearly 1.2 metric tons of CO₂ annually—equivalent to planting 50 trees per year.

Why Choose Subjee Cooler?

✅ Zero Energy Cost – No electricity or fuel required.
✅ Extended Freshness – Keeps perishables fresh 2-3 times longer.
✅ Eco-Friendly & Sustainable – Reduces carbon footprint and food waste.
✅ Affordable & Accessible – Designed for farmers, vendors, and communities.

After using the Subjee Cooler for a month, Im truly impressed!" says Ranjith Kullu from Talsara village. "I stored vegetables like bottle gourd, tomatoes, and lemons, and they stayed fresh for days. My bottle gourd lasted for about 7-8 days without any damage. Before this, we didnt have an affordable solution like this for farmers. Thanks to the Subjee Cooler, I was able to sell my produce at a better price in the market!

Mobile Subjee Cooler: Portable Freshness on the Go!

The Mobile Subjee Cooler is an innovative, energy-free cooling solution designed for personal vehicles, enabling farmers, vendors, and transporters to keep their perishable goods fresh while on the move. Whether delivering farm-fresh produce, flowers, or dairy products, this customizable cooler extends freshness without relying on electricity or fuel-powered refrigeration.

Subjee Cooler: A Natural Solution for Ripening Fruits

Beyond preserving freshness, the Subjee Cooler creates an ideal environment for natural fruit ripening—without additional water, chemicals, or artificial ripening agents.

How It Works:

???? Controlled Humidity & Temperature – The evaporative cooling mechanism provides a stable, slightly humid environment, allowing fruits to ripen naturally.
???? Ethylene Retention for Faster Ripening – Many fruits release ethylene gas, a natural ripening agent. The enclosed space of the Subjee Cooler concentrates ethylene, promoting uniform and natural ripening without external chemicals.
???? No Additional Water Needed – The moisture levels are self-regulating, eliminating the need for spraying water to maintain humidity.

Benefits of Using the Subjee Cooler for Fruit Ripening:

✅ Chemical-Free & Safe – Avoids artificial ripening agents like calcium carbide, ensuring healthier, more nutritious fruits.
✅ Even & Controlled Ripening – Reduces spoilage and uneven ripening common in open-air storage.
✅ No Extra Energy Required – Works without electricity, making it ideal for farmers and vendors.
✅ Longer Shelf Life – Fruits ripen naturally while maintaining texture, color, and taste.

The Subjee Cooler provides a sustainable, cost-effective solution for both fruit preservation and natural ripening, making it an essential tool for farmers, retailers, and organic food enthusiasts.

Want to Know More?

Coming up next: “Discover how the Subjee Cooler can optimize food storage, extend shelf life, and reduce waste.” Stay tuned!

Edited by Gayathri