Cooking Industry

ARUN®100 Solar Boiler / Solar Thermal concentrator with Thermal Storage atRamkrishna Mission Students Home, Chennai

The Project:

Ramakrishna Mission Students Home, Chennai wanted to install a solar thermal system to reduce their dependence and incremental expenditure on LPG used for cooking.

Requirement as stated by the client:

• Heat / steam required for cooking breakfast, lunch, snacks, dinner for 700 students
• The project should be handled on turnkey basis including complete integration with the existing system
• The solar thermal installation should occupy minimum footprint area

Requirement analyses by Clique Solar:

• Breakfast preparation starts as early as 4 am. Thus, steam required during non-solar hours as well

Recommendation Made:

1 ARUN®100 solar thermal concentrator with energy storage arrangement generating 540 kg of steam/day during solar hours on a clear sunny day, satisfying the complete energy requirement for cooking and hot water, resulting in 100% LPG fuel saving of 30 - 40 kg per day (depending on the usage).

Installation of the Project:

The system was commissioned on 26thOctober 2013.

Project Highlights:

• Steam available round the clock though provision given for energy storage. Steam Storage has been provided for cooking breakfast at 4 a.m.
• System is installed on roof top of existing building
• Cooks about 2000-3000 meals per day

Project Summary:

Date of Completion	October 2013
Steam Delivery	7 bar steam / 170°C
No of meals cooked on solar	About 2,000 to 3,000 meals on a sunny day
Average Fuel Savings	30 to 40 kg of LPG on a clear sunny day




Integration Schematic:





Operating Philosophy

The basic aim of the control system in this integration scheme is to deliver steam to the existing boiler header and excess steam to be delivered to thermal storage for non-solar hours operation.

The ARUN dish automatically tracks the sun from morning to evening. The receiver coil at the focus of the dish transfers the heat of the sun to the heat transfer medium (water). “The Steam generation system with Storage” consists of ARUN®100 dish, thermal storage, pumps, valves, etc. Once the system starts generating steam and required pressure is achieved, the steam is delivered to the common header of existing boiler system. If there is reduction in steam usage by the process (due to holiday, break, etc), the upstream pressure increases causing a valve to open, thereby delivering steam to the storage tank. This process continues whenever the sun is available. When the sun is not available, steam is first generated from the storage tank. Thereafter the existing boiler system is turned on.




ARUN®100 Technology Details

Aperture Area	104 sq.m.
Footprint Area	3m x 3m = 9 sq.m.
Temperature Rating	Peak delivery of 350°C
Thermal Output Rating	Peak delivery of 3,50,000 kcal/day
Tracking System	Fully automatic two-axes tracking system
Estimated Life of System	20 years +




Need for Thermal Energy Storage in Cooking

A typical energy requirement in community cooking setting is shown in the graph below in blue line. The red curve shows the energy generation with solar system. It is seen from the above graph that there is a mismatch in timings between the cooking energy demand and solar energy supply. The red shaded area (solar energy delivered in excess of requirement) is stored in a thermal storage tank. It is used at times when solar energy is not available for the cooking requirement (blue shaded area).