Wilson’s design is simple, if unusual. The cooker uses a plastic lens, a thermal "battery" (lithium nitrate salts), and insulated storage to store heat after the sun goes down. During the day, sunlight concentrates on a metal plate that heats up molten salts reaching temperatures as high as 482 degrees F (250 degrees C). As evening approaches, the lens is replaced by a cover. The molten salts stay searing hot for up to six hours. When it’s time to cook, simply open the cooker and start.

If all goes as planned, Wilson’s stove may finally succeed where decades of efforts to replace coal, wood, and dung fuels in developing countries have failed. The consequences for the environment and public health in poor countries has been disastrous: 2 million people die each year from indoor smoke and wood gathering destroys vast swaths of forests. So far, the sun simply hasn’t competed on price, convenience and ease of use with other fuels. The Proceedings of the National Academy of Science reports that 94% of Bangladeshi women surveyed knew cooking smoke posed a serious health hazard but most preferred to spend their money on "doctors, schools, electricity, clean water, latrines, seeds for planting, and structures to protect their land from flooding," not cleaner stoves.