Solar cooker concentrator of the box type, using cpc-type optics

Abstract

Solar cooker of the concentrating type, using Compound Parabolic Concentrator type optics (2, 2') comprising a box (1), inside which all its accessories and cooking utensils can be carried; the box being essentially made of plastic compatible with the production of complicated curves characteristic of the referred optics. The present invention includes a version in which electrical energy is used as backup for days without sunshine. Its application extends to other areas beyond the cooking of foodstuffs, in particular to the pasteurisation of water, milk and other products and its usage as a drying system.

Description

1--OBJECT OF THE PRESENT INVENTION[0001] The goal of the present invention is a solar cooker, simultaneously of the box type and concentrator, by the explicit use of Non-Imaging Type Optics, also referred to as Ideal or of the Compound Parabolic Concentrator Type (CPC), to cook food in temperature and power conditions higher than the ones used in conventional box cookers, but conserving and even improving the working characteristics of those cookers, in particular in what pertains to stationarity and control of cooking time. Another fundamental aspect of this invention is the achievement of great sophistication for the optics used together with low fabrication cost, from a materials point of view and from the point of view of the fabrication process, given the choice of plastic for both the external envelope and the inner cooker structure. The solution established by the present invention is the first one to allow the fabrication of solar cookers in large series production, with a t...

AI Technical Summary

Benefits of technology

"The present invention is a solar cooker that combines the benefits of box type and concentrator type cookers, with the use of Non-Imaging Optics that allow for ideal concentration of solar radiation. This results in higher efficiency and lower cost compared to conventional concentrator type cookers. The optics are designed to optimize the incident solar radiation during the maximum number of working hours. The invention achieves these improvements by integrating the necessary concentrating optics into the box itself, with an exterior augmenting reflector. The use of augmenting reflectors is also made in an integrated fashion with the inside optics, sharing in this way the Non-Imaging optics characteristics. The invention can be produced in large series production, with lower fabrication costs and improved efficiency compared to conventional concentrator type cookers. The invention can also be used as a pasteurizer and dryer, solving the problem of low efficiency and control of cooking time in these applications as well."

Problems solved by technology

The ones in the first category can be truly stationary, but have the inconvenience of presenting a low global efficiency, a less efficient and lower power delivery of energy to the cooking vessel.

The best on the market are produced with expensive materials and with characteristics designed to alleviate at least some of the referred deficiencies, but, as they are "hand produced" or, at best, in small series production, they remain an expensive product, thus with little value for the very large number of potential users in third world countries, presently and daily using wood, an ever scarcer resource, whose use is one of the main causes for the amazing and dangerous deforestation taking place on a world wide scale.

The ones in the second category are less practical, demanding the presence of the cooker for the tracking of the concentrator, are usually more expensive and have serious inconveniences associated with the risks of concentrated radiation on the eyes of the user if they come inadvertently into the focal zone.

These different concepts strive to achieve improvements in the most common and classic box type solution, through specific solutions, which may end up becoming very complex (and expensive!).

None of these, however, considers the possibility of direct improvement of the box type cooker, by incorporating in the box itself the necessary concentrating optics able to solve the problem in an ideal fashion, i.e. in the limits fixed by First Principles in Physics.

Images