Solar Cooking

• Overview (Below): For general information on success in spearheading successful solar cooking projects
• Article (Below): Reprinted with permission from SunWorld magazine.
• Molded SUNSTOVE®®: Specifications for this effective solar cooker.
• Fabricated SUNSTOVE®®: Detailed materials and drawings requirements
• The Refugee: A Solar Cooker for Emergencies, Made with Local Materials
• Cookbook: The most basic solar cookbook you’ll find available.

Overview: The Features and Qualities Necessary for the Acceptance, Manufacture, and Distribution of Large Quantities of Solar Cookers.
by Richard C. Wareham, 10/1/99

Past successes and failures are the keys to establishing a successful solar format for solar cooker programs to determine the ideal features of a solar cooker. There is no question that solar cookers work — hundreds of different designs and models have cooked for years in many countries. By reviewing these programs and designs answers can found to build the “best” unit and to develop the best format for a successful solar cooker program.

The largest solar cooker programs developed and subsidized by the governments of China and India. Smaller programs have been and are still being operated by various charities, service organizations, NGO’s, etc. There is one common thread in most of these projects — the solar cookers are given away or heavily subsidized. When the sponsor stopped funding, the program stopped or stalled. Also, most commercial manufacturing of solar cookers discontinues due to financial losses.

Point one. Solar cookers must be profitable for a business or self-supporting for a non-profit organization to manufacture ongoing production.

When selling a solar cooker to a potential user, the first question asked is: “What does it cost?” A good, low price cooker isn’t everything; it is the only thing. Since the mass market for solar cookers is for the impoverished in underdeveloped countries, time payment programs for the user and initial consignments or support for the local distributors are necessary. Governments and sponsors are needed to supply this initial support. NGOs, service organizations, and religious groups are needed to use, approve and demonstrate the cooker. However, the most successful distributors have been farmer coops and businesses who have displayed the unit and sold it for a profit.

Point two. The price of a quality solar cooker must be as low as possible and must include a profit for the seller.

“What will it cook?” is the next question. In Africa, the average person eats one Kg of food per day. The basic food is cornmeal with a vegetable side dish. Families of five or more are common. Therefore a unit should be large enough to cook five Kg or liters. Areas with 4kw or more per sq. meter per day of solar energy is the most successful for solar cooking.

Point three. A large cooker is desirable, but the cost and weight will limit the size. Cost increases faster than size. The cooker must be lightweight so that one person can move it, adjust it or hang it in his/her home.

“How do I use it?” is also asked. How solar is captured varies with the type of solar cooker. Parabolic cookers require almost continuous adjustment. Cookers with four external reflectors require frequent focusing to reach their high temperatures. Box cookers should be adjusted every hour. Panel cookers require the least adjustment but they collect and retain the least solar energy. (Insulated panel cookers are better.) Continuous attention is difficult since most people have other work or demands on their time.

Point four. The cooker must be user friendly, i.e., require minimum attention and adjustment.

Other features for an acceptable, successful solar cooker are l. Good quality and long life. 2. Rugged enough to withstand the frequent handling. 3. Clean easily. 4. Economical and easy to ship even for a short distance. The cookers should stack or nest so that they can be moved (even short distances) and easily stored by the user or selling organization.

POINT FIVE. The final and most important condition for a successful program is: The solar cooker must be built in the country where it is used, and the materials must be locally available (preferably made in that country).

The market and the greatest need for solar cookers occur in underdeveloped countries that have limited domestic materials and few manufacturing facilities. Most countries in the world do not have extruders, molders, laminators, etc. and they do not manufacture cardboard, sheet metal, plywood, aluminum foil, Fiberglas, mineral wool, felt, widow glass and plastic sheet, film or bags. These materials and the other items purchased from overseas companies with “hard” currency. The cost of materials, freight and duties make importing solar cookers or the materials to build them, expensive and difficult.

There are some exceptions where the market, materials, and manufacturing facilities are available to mold or fabricate almost any solar cooker in the same country, i.e., the SUNSTOVE® is molded and assembled in South Africa. We hope that these non-profit groups could supply the neighboring countries. However, for eight (8) years, the SUNSTOVE® Organization has tried to export. Some success when Rands or Dollars were available, but because of “hard currency” requirements, import duties, and freight costs, exports to most of their neighbors had limited success.

For the vast majority of countries, the answer is to use local materials to produce a solar cooker of reasonable quality. Materials normally available in all countries are scrap aluminum off-set (lithograph) printing plates for the reflectors, exterior and interior, scrap textile cuttings, wool, cotton, hemp, jute, sisal, carpet, rug, blanket, etc. for insulation; and wood for a frame. The glass, plastic sheet or film used for the solar window are not normally manufactured domestically, but commonly stocked. If scrap is available, use it.

A fabricated “SUNSTOVE®” has been manufactured for nine (9) years with these local materials by Mazahua Mission in Mexico.

Lithograph printing plates are available in every country at the government printing office, the local printer, or the local newspaper. Used printing plates sold as scrap. In semi-developed and developed countries, these aluminum plates are available in almost any quantity. All of our data and drawings for the “SUNSTOVE®” solar cooker based on the Heidelberg #102 printing press plate, 770mm x 1030mm, which is common throughout the world. Printing plate sizes from other presses can be used but may have to be riveted together or trimmed to size. All printing plates must be cleaned on one side for reflection and to be suitable to touch food. Do not clean the side away from the sun or food — the ink makes a good primer for those areas you want to paint: i.e., the lids (tops) of the cooking pans.

We at the SUNSTOVE® Organization are available to assist you in designing a cooker using these materials. The molded “SUNSTOVE®’ can be purchased fob Johannesburg — copy it and mold your own. Your local international shipping agent must make all financial and shipping arrangements since the non-profit groups in these countries do not have export or shipping departments and cannot finance other potential manufacturers. The metric drawings to hand fabricate the “SUNSTOVE®” are on this Web site. The design and name are free for all to copy and use. Use the registered name, “SUNSTOVE®,” when manufacturing and selling the “hometown solar cooker” to identify this solar cooker construction and design.

Good luck on your projects.

Tip of the day. When using any solar cooker, place it next to a brick, adobe or concrete wall that faces the Sun at noon. The wall will give some protection from the wind, reflect solar energy to the cooker and absorb (store) solar energy. All of these will improve your cooker’s performance.

Article Printed with permission from SunWorld Magazine, Vol. 22 No. 4, December 1998

THE INTRODUCTION AND PROMOTION OF SOLAR COOKING

Volunteers Margaret Bennett and Liz Perry were responsible for a field study by the SUNSTOVE®® Organisation of a two-year marketing, training and distribution program in South Africa. This article extracted from their report.

A marketing initiative

A demonstrators’ incentive scheme, proposed by SUNSTOVE® in South Africa gives the potential entrepreneur, payment for six (6) months (or at least for 45 demonstrations (@ R100 per demonstration), by which time a market should have established in the area for the SUNSTOVE®. A simple cash-flow forecast demonstrates that the entrepreneur will be self-sufficient and able to operate her business free of debt. This approach was considered (by the SUNSTOVE® Organisation) as a marketing experiment. The money spent on each demonstrator served the purpose of promoting and demonstrating the SUNSTOVE® to people that conventional media may not reach. At the same time, using the opportunity, the project provides a revolving credit for the first consignment of 10 SUNSTOVE®. The Organisation is able to equip the entrepreneur with seed stock. By this means, and the support from both the Department of Minerals and Energy and SUNSTOVE® Organization, a sustainable operation is run by local people.

Evaluating the incentive scheme

The sale of SUNSTOVE® to the general public was a success during the period of the project. Well over 7,000 sold in virtually every corner of South Africa and other countries. The areas where the demonstration incentive scheme operated were monitored closely. During the project, the volunteer evaluators made 28 trips into rural areas, traveling close to 30,000 km. As a result, they have reported a wide range of case studies. Documenting the success and failures they encountered. This documentation provides the basis for addressing misconceptions held about solar cooking, as well as making key recommendations.

Obstacles

The original intention was to contact and assist local organizations. It has proved to be impractical. Suitable, committed NGOs are few and far between. The ones that truly work in rural communities, with grassroots connections and regular contact, were often found to be the ones with the lowest profile and poor funding. Consequently many have fallen by the wayside. All too often the funding that is available dictates the direction of their programmes, and their focus changes with the funding climate.

While operating a project such as the demonstrators’ incentive scheme, organizations expect the need for funding to help with overhead and employ personnel to demonstrate SUNSTOVE®. Many NGOs lost interest in us when they discovered that SUNSTOVE® was not a funder per se. Conversely, others who would have happily carried on the program ran out of money.

Not one Organisation showed any interest in becoming self-sufficient (and thus perhaps independent of funding). The prospect of making money by selling SUNSTOVE®S was not a motivation. Even when we identified fieldworkers with whom to work, we discovered that their interest in making money for the group was minimal, even if their job depended on the Organisation’s viability!

Because of the difficulties with NGOs, we also tried various government departments, those with portfolios such as health, nutrition, environment, forestry might expect to have interests coincidental with our project. Unfortunately, these seemed to lack the capacity to run community outreach programs, or the will to do so. Useful contacts made with individuals in a couple of provincial Government departments and, because they are well motivated, these people will find the time and means to assist.

The conclusion, therefore, is, that this and similar projects, would do better to concentrate primarily on individuals within an Organisation running a business for their gain. With an Organisation to support them, the potential entrepreneur will do better. As long as the Organisation has as its focus an environmental or a community health outreach, then they should not grudge this support, not least because they could use the SUNSTOVE®S to attract interest in their work.

Addressing misconceptions

There is a school of thought that believes that only when the better off, often white, housewives use a solar cooker, will there be a “trickle-down effect” that would influence poorer people to emulate them. Whilst this might be happening in some areas, there is no direct evidence. However, when hundreds of SUNSTOVE®, are sold by a Co-op in Upington, one supposes they cannot all be going to white farmers. In the vast area of Jane Furse in Northern Province, it is black people buying SUNSTOVE®, on the recommendation of their peers. So it was concluded that one more obstacle to the introduction of solar cookers might not be a valid one.

Another perception is that because the use of solar energy for cooking is not “traditional,” it will be met with resistance. The assumption is that foreign technology will appear as invasive and threatening. Our conclusion, however, is that the perceived barrier of traditional culture is at least questionable. It was never mentioned by a rural woman (only men, who also had other interesting and wrong perceptions about their women). It seems to be used by people who can’t be bothered to find a way to make solar cooking viable in rural communities. If it were true, then nobody in a rural area would be using a primus stove, a gas cylinder, or electricity! The latter should have been difficult to promote since it must seem magical, unpredictable in its delivery system, and, not to mention being dangerous.

Yet another assumption that we conclude to be ill-founded is that poor communities care nothing for the environment. Our studious avoidance of this aspect of the project, when talking to rural people (because, we worried that for them, it is a non-issue) now seems presumptuous. This local interest in preservation is highlighted by the UN Volunteer Programme Report, “Our love for nature runs deeper than you think.”

Recommendations

1. In future programs should concentrate on the principle of self-interest and empower rural entrepreneurs to do business for themselves locally. These people must have good connections within their community. These local connections will help them keep track of creditors, and they will automatically have the trust of friends and neighbors.
2. Efforts should continue to discover suitable NGOs to work with (i.e., through which to contact individuals), advertising might be a way forward, but only if sponsored since to pay would mean increasing the unit price.
3. Further promotion for solar cookers and other household uses for solar energy should be supported by government departments.
4. Whatever demonstrators’ incentive or business plan used to establish these entrepreneurs, it should focus on becoming sustainable as quickly as possible. This path can happen, with only a small outlay like that given by SUNSTOVE®. It would be infinitely better to do this rather than loan money. While some local microlenders have been successful, there are documented instances of the pitfalls attending loan schemes.
5. Investigations should support entrepreneurs with subsidies used as market-based instruments to manage the environment. (S.A.Department of Environment Affairs Discussion Document 4: “Where appropriate, environmental resource economic measures should be employed to promote the use of appropriate innovative technologies that make a specific contribution towards sustainable development.”)
6. Any future project or outreach program considered should be planned to combine all possible information regarding solar energy technology. This synergy makes better use of funding and the energy of the project leaders. It would also seem obvious that some effort made to promote fuel-conserving stoves as well.

Success

“In the Northern Province, we have the clearest demonstration of the acceptance of SUNSTOVE® by rural women. A video was recorded for an SABC TV programme. This acceptance was made in the villages, and the women showed using and talking about the SUNSTOVE® did so completely spontaneously. One of them says “This is like having a second wife!”. We have been taken to villages to see SUNSTOVE® in use and told that it is particularly good for cooking cow’s stomach because it keeps the smell out of their inside kitchens. No one ever mentioned that the use of solar energy conflicts with their traditions or culture, and women have taken to its use like ducks to water. Men told us of the problems with witchcraft in the area; women never mentioned it! Men told us that their womenfolk would miss the camaraderie of the wood-collecting expeditions. Women have no trouble finding things to do with their time and energy!

Financially, the project is quite sound. R5830 owed for the 40 SUNSTOVE® and assorted pots taken since the end of 1995. Of this, R4650 has been repaid (and 5 SUNSTOVE® and pots are still in stock). The repayments comes in slowly, in some cases only R10 per month. We have suggested that, with the new Business Cash Flow Plan, they ask for at least R50 down and R25 monthly. This payment plan now is done, and increasingly, we are seeing buyers pay upfront. We intend to gradually wean the entrepreneur away from being in arrears with their repayments until they buy SUNSTOVE®S with their capital. The income varies from R40 per set (of SUNSTOVE® and pots) sold to cash buyers to R60 per set for buyers on terms.

Prospects

At the request of the Training and Rural Development Consultants (TRDC), we made a trip into the center of Lesotho. This Organisation is responsible for reparations and compensation made to “severely affected persons” in the area of the new Khatse Dam. Lesotho could hardly be more deserving of our attention. It was a common event to see donkeys laden with uprooted bushes to be dried as fuel. However, while we had ideal weather for demonstrations, we were told that usually, it is very cold and windy, and due to the inaccessibility of the area, the costs of transport would be very high. There was lots of interest in our demonstration, particularly when we brought up the subject of a possible income from retailing locally. The TRDC bought 4 SUNSTOVE® which they placed in widely spread communities. It is possible that with the support of TRDC, the project might go forward in Lesotho.”

Problems

Swartberg Community Development Association operated under the auspices of Rural Foundation were one of the first groups to join the project and sign the Letter of Accountability. They took 30 SUNSTOVE®S that they sold both in their area near Kostad and in nearby Lesotho. All were paid for, however, the group has folded as all their funding was stopped. It seems that Rural Foundation has fallen on hard times and lost valuable community workers like these ladies in Swartberg.

A note from the SUNSTOVE® Organization

Field support in South Africa, Botswana, Namibia, Zimbabwe, Lesotho, Swaziland, and Mozambique, is needed to locate and finance local women to sell SUNSTOVE® units for income. Shipping from South Africa is economical by truck or rail. As of August 1998, Rotary in India is sponsoring a program for SUNSTOVE® production and distribution there. Assistance and suggestions for SUNSTOVE®’s work in Southern Africa and India are invited.