Different methods have evolved over centuries. Now an Italian tech company, “PuroSole” (PureSun), has developed an innovative installation that is able to roast coffee beans with renewable energy.
The three co-founders of this project are two electronic engineers, Antonio Durbè and Daniele Tommei, as well as their longtime friend and coffee lover Luca Del Bufalo.
They spent almost six years developing an efficient way to use solar power.
“This project came to life because we are part of a robotic and IT company that had the curiosity to use heliostats (reflectors) that are devices used to direct the sun, solar power, toward a target,” says Durbè.
“Then, we met a friend of ours, he is a coffee lover, and he suggested us to use this technology to build a coffee roasting solar plant.”
PuroSole’s technology aims to drastically reduce the cost of large thermodynamic plants.
To do so, they came up with a small motorized reflector (heliostat) that they say is totally autonomous and self-sufficient.
“The sun, reflecting on the mirrors, comes across a sensor positioned in front of these rotating mirrors, then this sensor calculates the angle of the incident light and keeps it steady during the entire process,” explains Tommei.
“This way, the mirrors keep redirecting the light to the same point. The precision (of this) is pretty high, we are talking about fractions of grades for the whole day, so this allows to position the pointing even at tens, hundreds of meters away from where the heliostats are positioned.”
The company now also makes its own coffee, and sells it online.
Doctor Giuseppe Longo, owner of a pharmacy in the center of Rome, is a regular customer.
“I find this coffee very aromatic, not rich and, among all coffees I drink, this is one of the best for its taste and digestibility,” says Longo.
The installation relies on roasting the beans directly.
“It’s the coffee, not the rotating basket or the air in it that we are heating, it’s the coffee itself being heated, the sun’s rays hitting coffee beans, heating them and causing the heating of the air surrounding it. But, essentially, the warmest part of all of this is the bean itself,” says Tommei.
PuroSole offers a range of solar plants able to roast 10 kg to 200 kg of coffee per day.