SOLAR COOKER

Development of a Comparative Framework for Evaluating the Performance of Solar Cooker

Abstract

Large environmental, health, social and economical problems are connected with the use of fossil fuels and, in a dominating part of the world, also the use of firewood. The goal for this project was to develop and design an optimal solar oven system intended for food cooking and water pasteurisation. Further the advantages and disadvantages, compared with other energy resources were evaluated. Tests were carried out in Sweden as well as in Sri Lanka. An extensive range of prototypes were tested and sifted out to a small number of designs that were tested in Sri Lanka. A large number of evaluations and tests were carried out on many different materials, among others tests were conducted according to the international standard “Testing and Reporting Solar Cooker Performance ASAE S580 JAN03”. The report shows a number of benefits compared to previous reports on the subject, for example the development of indoor tests, the extensiveness and objectiveness of the tests, and the fact that the report combines extensive practical test results with solid theoretical background information. The test resulted in two solar ovens with the same parabolic design but made out of different materials. One oven is cheaper, simpler to produce and is considered for the target group poor people in developing countries. This is made out of a corrugated cardboard that is covered with aluminium foil. The second oven is more expensive but also more durable and is intended for more wealthy people in the west that wants a good alternative to regular ways of cooking food. It is made out of aluminium plate and mirrors.

Table of Contents

Development of a Comparative Framework for Evaluating the Performance of Solar Cooker5

01. Introduction5

02. Types of Solar Cookers Design7

2.1 Box Solar Cooker8

2.2 Panel Solar Cooker8

2.3 Parabolic Solar Cooker9

Parabolic Cookers9

03. Performance & Costing of Solar Cooker9

04.Existing Testing Standards of Solar Cooker13

4.1 American Society of Agricultural Engineers Standard ASAE S58013

Temperature Sensing14

Water Mass15

Tripod and Lamp Settings15

Recording15

Calculating Cooking Power16

Plotting16

4.2 Single Measure of Performance17

4.2 Basis for the Bureau of Indian Standard Testing Method19

4.3 European Committee on Solar Cooking Research Testing Standard21

Approach25

Classification of solar cookers25

Power and efficiency of solar cookers26

Measurement guidelines28

Considerations with respect to north-south plane31

General31

Costa Rica32

Some other countries32

Conventional means of cooking and their consequences33

Fuelwood / agricultural residues33

Shortage of firewood33

Cost33

Transport33

Efficiency33

Health / social34

Deforestation35

Fertilizer and erosion of soil35

Alternative means--solar cooking36

Temperature required for cooking36

Technical aspects36

Initial cost37

Number of meals cooked with solar oven / cooker38

Family level38

Indirect emission of CO240

05. Development of New Testing Standard of Solar Cooker41

5.1 Solar cooker use rates42

External conditions44

Change in interest44

Stove characteristics44

Lack of black cooking pots45

Savings associated with solar cooker use45

06. Controlled Factors46

Loading46

Tracking46

Temperature sensing47

07. Environmental Factors47

Wind47

Ambient temperature48

Pot contents temperature48

Insolation48

Solar altitude and azimuth49

08. Conclusion49

9.Reference53

Development of a Comparative Framework for Evaluating the Performance of Solar Cooker

01. Introduction

Great environmental, health, social and economical problems are connected with the use of fossil fuels and, in a dominating part of the world, also the use of firewood. Examples of problems are increasing deserts when forests are devastated, respiratory and health problems caused by fire ...