Patrick Walsh and Anish Thakkar weren?t trying to build an empire when they started in 2007. They just wanted to replace smoky kerosene lamps with something cleaner. Nearly twenty years later, that simple idea has grown into Sun King, the world?s largest off-grid solar company, lighting 25 million homes across Africa and Asia and raising over $700 million in funding.

It started the way so many lifelong partnerships do ? two friends in college, a half-formed idea, and a lab filled with half-working gadgets.

Anish Thakkar and Patrick Walsh met nearly twenty years ago at the University of Illinois. Back then, they weren?t dreaming of building the world's largest off-grid solar company. They were just two curious students trying to make a difference in entirely different ways.

Patrick was deep in engineering, working on a nonprofit project in India through Engineers Without Borders. He was in the state of Orissa, building biofuel microgrids for villages that had never known what steady electricity felt like.

He was walking a different path. He was running a nonprofit called Illini 4000, a student-run cycling organization raising funds for families battling cancer across the U.S. His work was about people, about finding light in dark times, in the most human sense.

But their paths crossed in a tech lab, where Patrick was drilling holes into PVC tubes, fitting LEDs through them, and experimenting with how to build a prototype solar-powered lantern he could actually sell to families in India who didn?t have electricity.

Anish was drawn in, not just by the idea, but by its humanity. ?It was the first time I realized,? he says now, ?that engineering could do more than design gadgets. It could change lives.?

That small dream would grow into Sun King, the world's largest off-grid solar company, powering over 100 million lives across Africa and Asia.

By 2007, the idea had outgrown the lab, and SunKing was born. The goal was to design solar products that worked for off-grid homes, were cheap, and reliable.

But the dream was fragile. They had prototypes, ambition, and not much else.

"We realized early on that just having the right product wouldn?t solve the problem. We also need a way to reach the people who need it most. And you need to make it affordable.? Anish narrated.

That realization changed everything. Anish quit his consulting job at ZS Associates and went all in. Funding was needed, and he was bold enough to go looking for it in unusual places.

The first yes

At his company's 25th anniversary party, Anish spotted one of ZS Associates? co-founders, Dr. Prabha Sinha, across the room.

He cornered him and gave him a one-minute pitch. ?He asked if I was still an employee,? Anish laughed. ?I told him no, I had quit a week earlier and was moving to India to start this business.?

Sinha, who had grown up in India studying under kerosene lamps himself, understood the problem he presented. He didn?t just believe in it, he backed it. Sinha later became their first seed investor, and he has stayed a mentor and board member ever since.

?That was the validation we needed,? Anish said. ?Someone who had lived through that experience believed in us, and in the idea that a for-profit social business could make energy accessible to everyone.?

Patrick nods. ?It?s been crucial that Anish and I remain in control of the board, founders still directing the mission, without decision-making being overly diluted. That?s how we?ve stayed true to what we set out to do.?

With that early support, they set up operations in Mumbai and built a direct sales network to distribute their first Sun King solar lamps to rural families.

Soon, their network of Sun King Saathis (local agents) was delivering solar light across Indian villages. From there, they looked west.

Their next frontier was Africa, where the need was massive. Nearly 600 million Africans live without access to electricity. But affordability was the real challenge. Most families simply couldn?t afford to pay up front, even for something that would change their lives.

So they flipped the model. Sun King invented its own financing system ? pay-as-you-go solar (PAYG). Customers could pay small amounts daily or weekly through mobile money or cash collection. As long as they paid, the lights stayed on. Eventually, they owned the system outright, and it changed everything.

Today, Sun King operates the world?s largest direct-to-consumer PAYG solar distribution network, having provided over $1.3 billion in solar loans to homes and small businesses.

SunKing has connected 25 million households, adding over 300,000 new users every month, and installed 195 MW of solar capacity across 11 African countries.

?What started as a product company became a full financing and service ecosystem,? Anish said.

Raising money for climate tech in Africa hasn?t always been easy. The space has grown, but it?s still catching up to the urgency of the need.

In 2025, though, the tide is shifting. Africa: The Big Deal reports that 39% of all startup funding this year, out of $2.2 billion total, went to climate-focused startups.

Sun King has been a key player in that movement. The company has raised over $400 million in equity and $300 million in debt.

?We used to think we?d always depend on foreign investors. But that?s changing fast. We?ve now raised over $450 million in local currency debt from African banks, Stanbic, Absa, and others. That?s huge.? Patrick said.

Those loans directly power solar purchases for millions of customers in shillings, kwacha, and naira.

?It?s no longer just donor money or Western capital,? Anish adds. ?It?s African banks fueling Africa?s green transition.?

Their landmark $156 million local-currency securitization in Kenya, the largest in Sub-Saharan Africa outside South Africa, proved just how far that model could go.

?The key was showing banks that solar customers are incredibly reliable. In some cases, their repayment rates are stronger than those of higher-income borrowers. That helped unlock major financing for Africa?s clean energy future,? Anish said.

Patrick calls it ?a quiet revolution in finance. ?Securitization is something you usually see in advanced economies. Now it?s helping rural families in Kenya and Nigeria access cheaper solar power. That?s transformative,? he said.

For companies serving a market as vast as Africa, the question often arises. Should production stay global, or come home?

Sun King just took the local route, opening its first major manufacturing hub in Nairobi, Kenya.

The facility will assemble solar-powered televisions and smartphones built to work seamlessly with Sun King?s off-grid systems. With a starting capacity of 700,000 units annually, and room to scale, it?s a major leap toward a fully localized supply chain.

Patrick said plans are also underway to set up a local assembly plant in Nigeria, producing not only solar kits but also the appliances they power, TVs, radios, and refrigerators, designed for homes where electricity remains unreliable.

?We?re building the next generation of green jobs,? said Anish. ?Over 35,000 field agents, 3,000 employees. That?s 38,000 careers created. These are the green energy jobs of the future.?

Patrick added proudly, ?Ninety-nine per cent of our 3,000 employees are African. That?s not by accident. It?s the whole point.?

When they talk about their two-decade partnership, both men smile before they speak.

?It?s trust,? Patrick said simply. ?We?ve been through good times and brutal ones. He?s one of the most important people in my life.?

Anish nods. ?It?s been an incredible journey. From soldering solar lanterns in a campus lab to powering millions of homes. But the mission is still the same: light every home that needs it.?

That friendship has become Sun King?s quiet backbone, shaping a company culture built on humility, long-term thinking, and shared purpose. ?We just feel privileged to work with people who care this deeply,? Patrick said.

For all their growth, more than $400 million in equity, $300 million in debt, and an active customer base across over 40 countries globally, Patrick and Anish still speak about the future with the same restless ambition that started it all. (Business Insider Africa)

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