Sunshine Cooking
I love my solar cooker. It is like a pet dog to me. First thing in the morning, I wheel it out to face the sun. I have been practising this cute system of cooking food for over 12 years. That is, in Trivandrum (capital city of the state of Kerala in the far south of India), an unlikely place for solar cooking because of the above average annual rainfall it gets.
The energy of the sun can be harnessed, very simply, to cook food. Sans complex lenses or systems. Iis beauty lies in its simplicity. On a hot summer day, the temperature inside a solar box cooker will easily touch 130 oC. Roasting nuts, baking cake, drying vegetables and fruits, baking fruits, making jams, I’ve tried my sun box for everything. Even restoring crispness to biscuits or banana chips made soft by Kerala’s forever-there kind of humidity. Calling it a mere ‘Cooker’ does it scant justice. It is more like an oven permanently switched on. You can place anything in it anytime and take it out when done. Can anyone ask for more?
The Indian army finds use for them in the icy heights of Kargil, Jammu and Kashmir. They were also put to good use in the aftermath of the Gujarat earthquake in 2001.
The solar box cooker made in India has a single reflector. The box looks like a square suitcase measuring 0.6 metre square and weighs about 12 kilogrammes. It usually has four cooking pots of aluminium or stainless steel. The cooker has castor wheels for easy movement.The outer case of the cooker is made of aluminium or fibre glass- reinforced plastic, which is light, tough, and can be fabricated in different eye-pleasing colours. Such box cookers are available in India for Rs 1500-2000 ($ 30-40), depending on the finish.
When using a solar cooker, be sure to be patient. One cooking session can take two to three hours, depending on the kind of food stuff being cooked. The cooker has to be moved occasionally, say, at hourly intervals, to face the sun as it moves across the sky. This would not be necessary if the solar cooker is directed at the sun’s ‘average’ position over the peak day. Food can be cooked only when the sun is shining and not early morning or late evening or when it is cloudy/rainy. Passing clouds do not matter. If there is a clear shadow behind the cooker, the sunshine can be considered good enough to cook. It is good practice to wheel out the cooker as soon as the sun is up on the horizon, for pre-heating reduces cooking time. If there is good sun for an hour at start, even intermittent clouding thereafter will not matter except delaying the cooking time somewhat. On a clear day, one can even do two rounds of cooking between say 9.00 a.m. and noon and again between noon and 3.00 p.m. There are so many advantages of the solar cooker, I never cease to be amazed. You do not have to be on your feet, in constant attendance. This is because the food never gets overcooked or burnt. A housewife can attend to other chores while the solar cooker is doing its job. Solar cooked food is also more tender food, and retains most of its nutritive value. Yes, when the food is done, you might want to do the typical Indian ‘tadka’i.e. tempering with herbs or spices. That’s it – a meal at zero cost in terms of fuel and in terms of the environment.
Yet, solar cooking has not caught on. Why? I suspect it is because most people do not know about it. Difficult, is it not, to comprehend the idea of cooking without a fire? Or strange to be cooking out in the open. One might think it a hassle to be sweating it out in the sun – far from it, for you don’t have to be out there attending on it . The truth is that unless you are introduced to it and see things for yourself you will not realize its extraordinary potential.
Again, I am not saying it has no drawbacks. The food takes time getting cooked, and cooking is impossible on days when there is no sunshine. This is true of PV (photovoltaic) devices also, except that the battery in the PV system can take the lag for a time. You cannot make chapatis (the Indian unleavened flat bread) or deep-fry anything. But let us view these drawbacks in the light of the great strengths of solar cooking.
I believe an effort should be made to convince people that these drawbacks are worth living with. The solar box is a lifetime asset. Handled with care, it can last 15 years or more. There is no moving part in it to go wrong. The only maintenance required is an occasional coat of black paint on the inside of the cooker and on the outer surfaces of the cooking pots. It is a system equally valuable in both the rural and urban settings. It saves the village woman long distances of trudging in search of scraps of firewood, a lifetime in a smoke-filled kitchen, and the messy cleaning-up of smoke-blackened pots and pans. For the urban housewife, it saves energy on kerosene and LPG (liquefied petroleum gas) and makes cooking easy, providing more time for other chores. The cost of petro- based fuels is going up all the time by the gradual withdrawal of the subsidies. The price of a cylinder of LPG has already reached Rs 260 and even this forbidding price has a subsidy element of 20%. This subsidy might also be phased out in the coming months and years.
The solar cooker makes you energy-independent. When buying a box cooker don’t look at only the initial cost; you must also consider that you will not be regularly milked for the fuel cost.
I would like to see the day when the mandarins in government, people’s representatives, celebrities, and public figures begin to set an example by using solar cookers in their homes. Solar cooking should be popularized through print and electronic media. It is such a wondrous way to cook. The lowly solar cooker deserves all the popularity it can get, and more.
There is another class of cookers called ‘concentrating cookers’ or ‘direct-focusing cookers’, which are concave (parabolic in shape) and reflect solar energy to a focal point where a cooking pot can be placed. Then there are parabolic steam cooking systems which consist of a number of these linked together. The world’s largest solar steam cooking systems are currently operating in the Brahmakumaris’ ashram (hermitage) at Mount Abu in Rajasthan, India and in the Venkateswars temple in Andhra Pradesh, India. Here, a hundred concentrators convert water into superheated steam. The system can cook for 10,000-15,000 people.
But for me the most useful invention is the solar cooker.Nothing can beat it. It can enter every household amd make a contribution to the environment movement gathering momentum around the world.
S. Narayanaswamy is the author of "Making the Most of Sunshine – Solar Cooking for the Common Man". This article is reproduced courtesy of the SOLAR POWER Newsletter.
