Steam Cooking System installed by Brahmakumaris at Mt. Abu

 
Concentrated Paraboloid Solar Cooker (CPSC) at Mount Abu, Rajasthan

The system, through all six of its modules, can generate 3,500 kg of steam per day, which is used for cooking water sterilization and preparing hot drinks. Although originally designed to cater for 20,000 meals per day, during periods of peak solar radiation the system's output has been sufficient to cook a maximum of 38,500 meals per day.

The Brahmakumari’s Vishwa Vidhyalaya is an International Spiritual Education Institution, recognized by the UNO under class 1 status operating with its headquarters at Mount Abu, Rajasthan. The world’s first largest solar steam cooking system is installed at their headquarters, Shantivan Complex, Abu Road, where more than 10,000 people daily visit, stay and have meals.
The Institution has received the recognition of being the first largest solar steam cooking system. Hence India is the forerunner in holding the title as having the world’s largest steam cooking system.

System Safety:
The system is protected against excess pressure by safety valves and an automatic shutdown mechanism. The status of the whole system is monitored by temperature and pressure meters and a computerized 6 channel data logger. Though the system is designed for 20,000 meals per day,
so far it has provided steam to cook 33,500 meals during peak solar radiation periods, and it seems its maximum capability can still be stretched. In between the gatherings, the output and the sorting capability of the system was excellent so that even at 4:00 AM sufficient steam for tea preparation for 15,000 people was available. During such periods the backup system could
be switched off completely.

A huge capital outlay of Rs.60 lakhs was spent for the installation of the CPSC at Mount Abu. Table 2 indicates the quantum of fuel saved through the use of the CPSC.

TABLE 2: QUANTUM OF FUEL SAVED

The quantum of fuel saved is directly proportional to the number of hours of usage of the system. Thus a total of 64,743 litres of diesel was saved through this installation of CPSC in one year. However in certain months, we could observe that even though the number of hours the system operated was long, the quantum of fuel saved was less. This can be attributed to the type of dishes prepared and the vegetables used for preparing meals. If one institution could save so much of fuel through the installation it is easy to infer how much fossil fuel can be conserved in a year if all such institutions adopt this technology.

Time Taken to Cook Selected Food Items:
All kinds of root vegetables, leafy vegetables and other vegetables were cooked through the steam cooking and served to the people (Table 3).

TABLE 3 TIME TAKEN TO COOK SELECTED FOOD ITEMS

The investigator observed the feasibility and effectiveness of the CPSC in preparing meals for more than 10,000 persons per day at Mount Abu. Due to the tapping of concentrated rays of the system, the steam generation was hastened and thus the preparation time was less. Hence the authorities could serve hot meals to any number of devotees assembled for spiritual discourses.

CONCLUSION
In conclusion, CPSC fulfill the criteria for practical applications: being technically feasible, eco-friendly, customer oriented, and locally available, and saving fossil fuels and providing more employment opportunities. If such technology is adopted on a large scale, the energy crisis can be solved in our country, a decisive step towards becoming a developed nation.

Author
Dr. Sathyavathi Muthu,
Professor – Resource Management,
Avinashilingam Deemed University,
Coimbatore – 641 043.
India.
(sathyavathimuthu@gmail.com)

Ms. Rachna Raman,
Research Scholar,
Avinashilingam Deemed University,
Coimbatore – 641 043.
India.

Capital costs of solar based Air Conditioning System of 160 TR
Per tonne (TR) of cooling one needs 3.7kg of steam per hr. For 160 TR you need 592 kg of steam per hr.  Each parabolic mirror of 16 sq metres area gives steam of 4 kg per hour. Hence one needs to install 148 parabolic mirrors.

Operating costs-Conventional System
Every Tonne in screw type chiller requires 0.9 units of power per hr . In Mumbai, Reliance Infrastrcture Ltd. supplies power to commercial consumers at Rs. 11.50 per unit. Assuming 12 working hours a day the 160 TR consumes 622,080 units a year                                   
Annual Power Bill                                                                     71,53,920.00

Operating costs-Solar System
Assuming that for 300 days in a year parabolic mirrors generate steam for 6 hrs a day. For these 300*6  ie 1800 hrs no fuel required. For the balance time ie 360days * 12 hrs = 4320 hrs minus 1800 hrs ie 2520 hrs Natural Gas is used. Natural Gas is currently priced at Rs. 13.54 per cubic metre.  

Conclusion: One can get same end effect of power generation by investing just Rs. 20000 in solar thermal technology, which otherwise requires Rs. 5 lakh investment in solar PV cost