Turning Rwanda's rivers into renewable energy
One of the business ventures that African entrepreneurs tend to avoid - perhaps in order to avoid a shock - is electricity.
It can be a highly capital-intensive enterprise, very risky, and the returns may not be felt for a long while.
But Rwanda's Gregory Tayi saw that as an opportunity.
Having supplied medical equipment, vegetable products and chemicals for many years, he decided it was about time to start providing electricity.
His country, like most African nations, struggles to meet its energy demands, and he realised that he could make a difference - and a profit - by putting up mini hydro-electric stations in some of its numerous rivers.
"We went to the government. The government had a fund that would subsidise the people who do go into this business. So all these factors helped us to enter into energy," he told the BBC's African Dream series.
"There was this subsidy but the bank also gave me the credit. They looked back at my history of business, at what I was doing before," added Mr Tayi, now the proud general director of Renewable Energy Promotion (Repro).
Starting from zero
According to him, for even the smallest hydro-electric station in Rwanda, one would need an initial investment of around $500,000 (£312,000).
But he says that having the capital is not the main point. He believes that it is much more important to be clear about where one wants to go.
"When you start from zero, you learn what you wouldn't have learned in school. And I think that's the most important capital that one can get."
He said he did not have an easy start. When he was a student, his family could not even afford to help him with his school fees.
He remembers that when he finished university, with a master's degree in chemistry, he was "as broke as anybody".
"I couldn't count on anybody. As I didn't get a job, I couldn't even sustain myself," he said.
Forced into business
Mr Tayi pointed out that for him becoming a businessman was not a choice.
"I was forced into it but, luckily, I was forced into business because I struggled for the first years but other years, you know, things came much much easier."
Repro opened in 2007 and its main power site, at Murunda, in Rwanda's Western Province, started three years later. It currently generates around $10,000 per month.
And how would he describe a good business person?
"When people look at businessmen, they look at money, but I think money is not what makes the person," he said.
"A business, it's working with the people. It's making life easier for others. A good businessman is the one who looks at his neighbours, at his countrymen, at the world," he explained.
"It would be meaningless if I were rich and I'm surrounded by poor people. A good businessman is one who looks first on others before he looks after himself."
African Dream is broadcast on the BBC Network Africa programme every Monday morning.
Every week, one successful business man or woman will explain how they started off and what others could learn from them.