BIOGRI doesn't use direct or indirect fire, heated plates, resistors or other electric components: only the sunlight, appropriately reflected, determines the cooking. As the sunlight is the main element for cooking, there are not substantial differences between summer and winter, but it is important when you use BIOGRI (the maximum radiation occurs in the central hours of the day) and clarity of atmosphere. BIOGRI reach the max temperatures of 230° - 240° (cooking occurs at an average temperature of 180° - 200°) and there are no times of pre-heating: foods immediately begin to warm when you expose it to the sun. BIOGRI is ecological: Anodized aluminium base, structure in natural wood, no paint with chemical solvents. Packaging is made with only recycled cardboard (not polystyrene, nylon or plastic). BIOGRI is easily transportable, with removable and lockable tripod. It also has a tray for collecting grease and cooking oil to avoid soiling the mirror, it is easily removable for quick cleaning. Adjustable skewer on 6 fixed positions (for homogeneous cooking), fit for automatic rotisserie battery.