Solar energy is a primary source of energy which is abundant in nature. It is an efficient renewable energy source, which may be used for various applications ranging from electrical energy generation through photovoltaic to cooking food through a solar cooker. Non-renewable energy sources such as the fossil fuels will be exhausted in the near future and hence, we have to maximize use of solar energy. In the present idea, the thermal component of the solar spectrum is efficiently utilized in a very simple manner, which may be used for various cooking and heating applications. The funnel-like structure of the device accumulates/focuses the solar radiations in a small area at the focal point. This accumulation of the solar radiations raises the temperature of any container which is sufficient for cooking and heating purposes. A bowl of rice could be cooked in just half an hour time. The simple and straightforward architecture of the system makes it a versatile solar heater for varied applications. It can find huge acceptance in places lacking electricity supply and having abundant solar energy resources.
The working principle of this instrument is very simple and is as follows:
1) Concentrating sunlight: A surface with high reflectivity is used to concentrate light from the sun onto a small cooking/heating area.
2) Converting light energy to heat energy: Solar heater concentrates sunlight onto a receiver such as a cooking pan.
The interaction between the light energy and the receiver material converts light to heat. This conversion is maximized by using materials that conduct and retain heat. Pots and pans used on solar cookers should be matte black in color to maximize the absorption.
3) Trapping heat energy: It is important to reduce convection by isolating the air inside the cooker from the air outside the cooker. Simply using a glass lid on your pot enhances light absorption from the top of the pan and provides a greenhouse effect that improves heat retention and minimizes convection loss. This "glazing" transmits incoming visible sunlight but is opaque to escaping infrared thermal radiation.
1) For more concentration of Sunlight, lightweight mirrors can be used in the 12 cells of the tomb-like structure of the device to accumulate the solar radiations in a small area at the focal point more efficiently as the reflection of the mirror is more than aluminum foil.
2) The device requires automatic rotation as per rotation of Sun during the day. This can be accomplished by affixing pulley and rotation of pulley can be arranged in a similar manner to the hour hand of a clock.
As the world population is projected to increase and the supply of the fossil fuel is projected to decrease, the increased supply of the renewable energy for the post–fossil fuel period is inevitable. This present design is a simple and efficient way of solar energy utilization. It will definitely attract people towards itself, because of its simple design, very less expense, and portable features.