American engineering student Scot Frank's solar-powered SolSource cooker was an idea born from spare time.
About a decade ago, he had just completed a semester of Putonghua language courses at the Massachusetts Institute of Technology and was heading for a three-month teaching job at a university in Qinghai province, in northwestern China.
When he arrived, however, he found that the professor there had neglected to tell the students that Frank, then 19, was coming, so they had all gone home for the summer. With no students, and a three-month stipend, he decided to travel and ended up in the provincial capital Xining .
"My mother always taught me there's always something good in every situation," laughed Frank, in California this week for a retail conference where there's plenty of interest in the SolSource cooker that in a sense came out of that first trip.
In Xining, Frank met a professor, who saw the potential of this talented engineering student teaching his more impoverished students.
Frank went with them to their homes, travelling hours into the countryside, before arriving in an area of Qinghai known for violent sandstorms and cold temperatures, but also for 330 days of clear blue sky each year: a perfect environment for solar energy.
Frank also met a Harvard University PhD student, Catlin Powers, who was studying climate change and air quality.
Both she and Frank were alarmed by the detrimental effects to health caused by the wood burning stoves in many homes in Qinghai. In fact, Frank said, it's a huge killer on the mainland - and while much attention is given to the pollution levels and smog in the capital Beijing, the air in these homes is 10 times more lethal.
So he and Powers combined forces with solar design firm One Earth Designs to create more than 50 prototypes of a solar cooker, whose inspiration came from the people in the countryside. While there are a number of cookers on the market, the villagers were able to stipulate their exact requirements to Frank for the stark and arid conditions.
Some of the cookers were too heavy, Frank said. Others were too high for often elderly Qinghai women, who would need to bend over the stove and pull off a steaming kettle, so there were dangers involved.
The final result was the SolSource, which weighs only 18kg in comparison to other models that come in at above 90kg.
The cooker can be revolved to follow the sun and is stabilised with a brake.
Frank explained how power was generated directly from sunlight reflected from a parabola of light plastic panels with a V-shaped gap for access by the user. The ring on which the pan sits, where the heat is focused, is waist height.
Frank and One Earth Designs have been nominated for the Spirit of Hong Kong Awards by the Hong Kong Science Park in the category innovation for greater good.
Frank noted that the village women often had to do highly dangerous and illegal foraging trips for wood at night. The SolSource not only saves them having to buy wood or essentially steal it, it saves the lungs of their children, and saves them money in the long term.
While Frank and Powers' primary incentive is designing a product that could serve the people of Qinghai, the SolSource has also become commercially successful in a number of other countries.
Not one to sit on his laurels, Frank said Qinghai's environment provided many opportunities for more solar solutions.
While he's concentrating on the SolSource cooker for now, he said there was potential to use solar energy to charge mobile phones in remote places, among other applications.
Frank is still very close to the communities he met on this initial visit and has travelled back many times - much to the chagrin of his professor back at MIT, who never thought he would graduate; he did.
But Frank's heart is back with the people of Qinghai. "It's important to have a long-term vision and perspective about what is important for our society and our planet," he says. "You can earn a lot of money in a short time and get rich quick but I think what brings personal satisfaction is to create something of value that also generates income."