The 300 kWp system was undertaken for CIS under Karnataka´s solar net metering policy, wherein energy produced is first consumed by the school and the excess is fed into the grid.
India is the fifth largest consumer of electricity in the world, producing almost 70 per cent of its electricity from polluting hydrocarbon-based generation plants, which emit CO2 and other green houses gases.
The country spends almost 10 per cent of its GDP in energy imports accounting for a substantial amount of foreign account deficit, when it is blessed with abundant solar energy. Solar energy is clean and holds the promise to make India energy independent.
Wanting to be change leaders and demonstrate by example to others that it is forward thinking and feasible to power an entire school by clean and renewable energy; CIS recognised the above challenges and decided to adopt solar energy to meet all their electricity requirements.
CIS approached New India Electricals Ltd to design and build a solar power plant on all of the school building´s roofs. The 300 kW project was sized based on the institution´s electricity consumption of the last 12 months and was implemented in a matter of just 45 days.
The grid-tied solar plant takes advantage of Karnataka´s progressive net metering policy, which uses the grid as a bank to upload excess electricity. The policy compensates the users for excess electricity fed into the grid.
The Government of India and Karnataka encourages the adoption of solar energy by giving various incentives such as zero import duty on solar panels, reduced taxes and duties. The payback of a typical solar plant is around four to five years.
Potential & Benefits
The solar plant is expected to yield 12 per cent project IRR, with the payback period being 4-5 years, considering the advantage of depreciation. It reduces electricity bills and the system automatically synchronises with diesel generators and thereby reduces diesel consumption. Complete data analytics of the electricity consumption, loads and solar generation is provided by the monitoring system installed on campus.
The solar plant at CIS is grid-tied, south facing fixed tilt rooftop plant on the flat roofs of the school and east-west facing on the sloping roof of the school auditorium. The School maintenance cleans the solar plant on bimonthly basis, besides custom water jets installed to clean dust and bird droppings. CIS has also installed two panels along with a meter for our students to see and understand how solar energy works.
The project was commissioned in January 2016 and the entire installation was required to be completed in 45 days with the installation team working round-the-clock to meet deadlines.
Multiple rooftops in the same campus also created a challenge and the solar PV panels had to be strategically arranged across these roofs to accommodate the 300 kWp capacity plant.
The solar PV system was synchronised with DG sets such that majority of the loads were taken away from PV system when the grid was down. This added complexity to the project but DG synchronisation meant reduced emission of diesel fumes.
Multiple documentation and approvals from CEIG and BESCOM, to co-coordinating and liaising with different agencies was another major challenge and was highly time consuming.
- JOCELYN FERNANDES
- CIS campus in Yelahanka is located just off the New Airport road.
- It is a 300 kWp DC capacity project, handling 75 per cent of the school´s power load.
- The project, commissioned in January 2016, uses a grid-tied rooftop PV system.
- Technology in use is thin film CIS procured from Japan.
- The plant is expected to produce 4 lakh units of electricity annually and hopes to save the school approximately Rs.25 lakh in electricity costs.
- CIS went live with their solar energy production and consumption on March 22, 2016, a date that marked their 20th anniversary.
- They were the first school in Bangalore to adopt solar energy for 100 per cent electricity needs.
- Any excess energy produced that is not consumed on campus, is exported to the power grid and redistributed to neighboring villages and homes.
- They are carbon neutral as a school and are doing our bit to reduce the world´s carbon footprint.
- The Solar Project system at CIS is one of the best performing solar PV plants in Bangalore with a performance ratio of 85 per cent.
- The solar plant has a weather station and a remote monitoring system to check the solar radiation and corresponding solar generation on a minute-to-minute basis.