How S4S Technologies turned wasted crops into profit for 300,000 farmers, empowering 2,000 women entrepreneurs

In India, a third of food grown never reaches consumers. Small farmers lose income as unsold crops rot, while rural women struggle for stable livelihoods. S4S Technologies tackled these linked problems with a simple idea – dry the surplus at the source – creating a model that cuts waste, boosts incomes, and empowers women. This story matters because it shows how reimagining a supply chain can transform trash into opportunity.

You can read the shorter version of this story on LinkedIn.

Company	S4S Technologies
Founded	2013
Founders	Dr. Vaibhav Tidke, Nidhi Pant, and team
Sector	Rural Livelihoods & Climate-Smart Agriculture
Headquarters	Mumbai, Maharashtra
Core Problem	India loses one-third of agricultural produce due to post-harvest waste.
Primary Solution	Solar-powered dehydration tech and a buyback model to convert surplus crops into shelf-stable food.
Business Model	Purchases surplus produce, trains women entrepreneurs to dry it, guarantees buyback, and sells to B2B clients.
Verified Highlights	• Won the 2023 Earthshot Prize (£1M funding) • Works with smallholder farmers and women entrepreneurs across multiple states (Earthshot Prize profile) • Partners include Nestlé and Sodexo (Forbes India, Earthshot Prize)

The Problem

India’s small farms produce more food than they can sell or store. Around 30% of crops are wasted before leaving the farm. Cosmetic grading causes buyers to reject ~20% of harvests outright, even if the produce is edible. With minimal processing or cold storage available, farmers have a narrow window to sell before spoilage. As a result, about $14 billion of food is lost each year in India. This not only means lost nutrition and wasted resources, but also lost income for growers – trapping many in poverty.

The Founder

In 2013, a group of college friends, including Dr. Vaibhav Tidke and Nidhi Pant, founded S4S (Science For Society) Technologies to fight this cycle. Vaibhav, a farmer’s son from rural Maharashtra, had often seen fresh vegetables dumped or sold for pennies at day’s end when buyers disappeared. Determined to extend the shelf-life of crops, the team developed a patented Solar Conduction Dryer (SCD) – a cheap, electricity-free food dehydrator that can preserve produce for up to six months. Their early innovation won awards and proved that even without refrigeration, farmers could save food from rotting. But technology alone wasn’t enough.

The Turning Point

For its first few years, S4S tried selling the solar dryers directly to farmers as a solution. Adoption remained slow. Farmers were hesitant – even if they dried their crops, who would buy the dried produce? The breakthrough came in 2019 when S4S changed its strategy. Instead of just selling equipment, the startup offered to buy back every slice of dried fruit or vegetable the farmers produced. This guaranteed market gave farmers confidence that they wouldn’t be stuck with unsold inventory. By closing the loop – providing the tech and purchasing the output – S4S unlocked the full potential of its idea.

The Business Model

S4S now operates a full-stack farm-to-factory platform. It sources surplus or lower-grade produce from small farmers and provides rural women with solar dryers and training to dehydrate that produce at the village level. Under this “drying as a service” model, S4S acts as a guaranteed buyer: once the women finish drying fruits, vegetables, grains or spices, S4S collects the output (now just 1/10th the weight) for further processing. The company then sells these shelf-stable ingredients to food industry clients – from giants like Nestlé and Marico to bulk buyers like Sodexo and airline caterers. By aggregating and refining the dried goods at its facility, S4S ensures consistent quality and volume. This integrated chain means farmers and women entrepreneurs get to share in the value addition, instead of letting their crops waste away. S4S essentially turns “excess” harvest into B2B food products, eliminating middlemen and post-harvest losses.

The Challenge

Implementing this model wasn’t without challenges. One hurdle was earning trust in remote communities. S4S partnered with local NGOs and co-ops to identify and train women entrepreneurs, building credibility on the ground. Another hurdle was finance – a solar dryer costs about ₹2 lakh ($2,400), a big ask for a small farmer. Most women S4S works with had never taken a loan and lacked credit history. To solve this, S4S arranged micro-loans through banks and acted as guarantor. Because S4S commits to buy the dried products (ensuring the women have income), banks were willing to offer loans at just ~6% interest. Entrepreneurs pay the dryer off over 5–7 years, although many break even within a year of operation. By de-risking the investment for both farmers and lenders, S4S overcame the friction that often blocks new technology adoption in villages.

The Impact

Women entrepreneurs in India use S4S’s solar conduction dryers to preserve crops that would otherwise go to waste. As of 2023, S4S’s network includes about 300,000 smallholder farmers and 2,000 female entrepreneurs running dryers across rural India. These women dryers have seen their incomes double or even triple, often earning up to ₹10,000 per month in drying season – a meaningful boost in communities where many lived on a few dollars a day. Farmers supplying produce to S4S benefit too: by selling what was once unsellable, they gain 10–15% higher profits on their harvests. By 2025, the company aims to reach 3 million farmers and 30,000 entrepreneurs nationwide. The environmental impact is also significant. By extending shelf-life and replacing polluting alternatives (some S4S dryers displaced diesel or coal-fired dryers), the model cuts food waste and avoids thousands of tons of CO₂ emissions that would have resulted from decay and inefficient logistics. S4S’s approach shows that empowering those at the farm gate can create a ripple of economic and ecological benefits.

The Outcome

S4S Technologies has evolved from a college project into an award-winning social enterprise. In 2023, it was named an Earthshot Prize winner by Prince William’s foundation in the “Build a Waste-Free World” category, earning a £1 million grant to scale up. This global recognition came on top of earlier support from impact investors – for example, Acumen and Factor[e] Ventures led a $1.75 million round in 2020 to fuel S4S’s growth. Today, the company has 120+ employees and operates in three states (Maharashtra, Odisha, and Andhra Pradesh). Notably, S4S reached operational breakeven by 2023 and expects to be fully profitable within two years – proving that an impact-focused startup can sustain itself. Looking ahead, S4S is eyeing expansion beyond India. The team has begun exploring markets in Africa and Southeast Asia, where small farmers face similar gluts and post-harvest losses. The ultimate vision is to replicate the model anywhere farmers struggle to get their crops to market.

The Insight

Solving complex problems like food waste often means tackling the entire value chain – from technology and training to market access. By thinking end-to-end, S4S turned an overlooked waste into a win-win for farmers, women, and the planet

Sources:

How S4S Technologies turned wasted crops into profit for 300,000 farmers, empowering 2,000 women entrepreneurs

The Problem

The Founder

The Turning Point

The Business Model

The Challenge

The Impact

The Outcome

The Insight

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