The Phaeton Array

Technological Brief

The Phaeton, developed by Fraser Symington and Lorin Symington of ASTRA is a powerful and novel perspective on solar cooking. It consists of an array of mirrors on a straight steel frame focusing on a secondary reflector which reflects the light upwards at a convenient working height of 30″. With 35 square feet or 3.2 square meters of collection area the Helios array achieves a 5min/1L boil. A pot with 8L of water will boil in 35 minutes with 1000w/m2 of incoming solar radiation.

The Phaeton is one of the most cost effective solar cooking solutions available today. In Puerto Peñasco in Mexico, we built a Phaeton for $364US. At any sort of commercial construction scale the cost will quickly drop to below $300US. At Mexican trade rates of $40US per day for a skilled tradesman and his assistant, labour costs would be $160US per array at the artisanal scale, falling to approximately $100US in a dedicated fabrication facility. This amounts to $400US for a 2kw household or small commercial, or community solar cooker with a payback time of approximately one year. Among the most versatile of solar cookers due to the high range of temperature it achieves, the Phaeton can bake, boil, fry, roast, dry, or distill. On the spectrum of solar cookers, the Phaeton is somewhere between the SK series of parabolics and Scheffler reflectors. The Phaeton is an attempt to overcome certain design limitations of parabolic dish cookers, which become unwieldy at large sizes and Scheffler cookers which though very convenient are relatively complicated and expensive.

The trade-off for such power and convenience is a long focal distance. This means that the Phaeton must be re-oriented approximately every 7 minutes. We have not found this to be a significant deterrent for several reasons: because an equivalently powered fire requires roughly equivalent tending, nearly anyone can re-orient the machine, the lack of soot and smoke as well as the perceived benefits of time and money saved.

The Phaeton is built with off the shelf materials that are available in any sizeable city in the world; 2mm glass mirror, common steel profiles, nuts and bolts and fibreglass are the major ingredients. The tools are found in any welder’s shop in any neighbourhood in Bamako, Mali, one of the poorest countries on the planet.

Above, we see the Phaeton heating a fruit and vegetable drier. We made 3 lbs (wet weight 18lb) of perfect tasty dried pineapple tidbits