PUNE: CSIR-National Chemical Laboratory (CSIR-NCL), Pune, has installed a solar thermal system for its in-house canteen cooking applications. It was recently inaugurated by Prof Ashwini Nangia, Director of CSIR-NCL.
A team from the solar thermal lab of CSIR-NCL had undertaken a study of the canteen to understand the practices in washing and cooking. The data was then used for recommending a suitable solar system and its integration in current heating practices. A solar based kitchen was demonstrated at CSIR-NCL’s canteen. The canteen offers breakfast, lunch and tea (morning and afternoon) to about 700 users.
“The solar thermal system is useful at different temperatures for various applications. Process integration of solar thermal towards cooking application according to requirement is a huge challenge,” said Nangia. The officials from CSIR-NCL said that the solar system delivers hot water in the range of 45-50°C for the washing section and 85-95°C for the cooking section separately. It reduces electricity requirement by 60-70 per cent in washing area and LPG consumption by 55 per cent for boiling process used for rice, tea, lentils, curry, etc.
The systems used are evacuated tube collectors (ETC) and compound parabolic concentrator (CPC) solar technologies along with storage tanks, steam cooking vessels, electric boiler and piping. The solar system at the canteen includes two ETC solar panels, which provide hot water for washing and three CPC solar panels that serve the purpose of cooking water. The volume of the tank on the roof is around 300 litres.
The storage of water overnight reduces water temperature by 10-15°C. An extra tank is installed in the kitchen where an electrical heating utility is provided, which can be used to fill the temperature deficit. It serves the purpose of supplying consistent hot water for cooking in all weather conditions, said scientists at NCL.
The solar system can also be useful for canteens, mid-day meal schools, orphanages, old-age homes, etc. “Hence, solar thermal systems for cooking application will definitely contribute towards using renewable resources, ultimately reducing LPG consumption and value addition towards savings in CO2 emissions for the environment,” said Nangia. “The expenditure for all the arrangements of the solar system is around Rs 6 lakh,” he added.