Over the years, telecom tower companies have realised the importance of reducing diesel usage and started adopting renewable energy solutions. The shift, however, has not been very significant, with renewable energy solutions being tested only at the pilot level or being installed in conjunction with diesel generator (DG) sets. In a bid to discourage diesel usage at tower sites and consequently reduce the telecom sector’s carbon footprint, the Department of Telecommunications (DoT), through a directive issued in January 2012, mandated stringent targets for implementing green technologies in the telecom sector. As per the directive, 50 per cent of rural and 20 per cent of urban towers had to be powered by renewable energy sources by 2015. The deployments need to go up to 75 per cent in rural areas and 33 per cent in urban areas by 2020. While the intent behind these guidelines was much appreciated, the guidelines were considered too ambitious, almost unrealistic, given the prevailing conditions in the industry. To begin with, tower companies would have to incur capex of Rs 660 billion to meet the targets by 2020. Given the financial condition of most players in the telecom tower space, matching these numbers would be a Herculean task. Moreover, the guidelines overlooked several technical and practical challenges, such as inadequate space for installing solar panels. The tower community also sought clarifications on the definition of rural and urban areas. Following a series of representations by the tower industry, DoT has now referred the matter to the Telecom Regulatory Authority of India for review. In the meantime, tower companies have taken initiatives to reduce diesel consumption to less than 30 litres per month and have declared these sites “diesel-free”. GTL Infrastructure Limited has about 6,000 diesel-free sites.
Case study: NEDO project
Japan’s New Energy and Industrial Technology Development Organisation (NEDO) had commissioned a joint initiative – Demonstration project of energy management system for reducing energy consumption by mobile phone base stations. This was based on a joint MoU signed in August 2014 by NEDO, DoT, the Ministry of New and Renewable Energy, the Department of Economic Affairs (Ministry of Finance), GTL Infrastructure Limited, and Viom Networks.
As part of this project, technology solutions were provided by Japan for deployment at select telecom sites. The project highlights are as follows:
- Solutions deployed: A broad mix of technologies and solutions were deployed to achieve the desired results. Solar photovoltaic (PV) panels with a total capacity of 2.9 kWp were installed at the sites (12 modules per site), with each module having a capacity of 242 Wp. In addition to solar panels, lithium-ion batteries were deployed for energy storage. A total of six units with a capacity of 3 kWh per unit were deployed at each site. An energy management system was used to monitor the solar radiation (PV power), battery state of charge power (EB power) and load power. Further, a switched-mode power supply system with a maximum capacity of 18 kWh was used. Other solution components included a change-over switch (grid, DG, battery, air conditioner) with remote control based on an optimisation algorithm and photocatalytic paint on the shelter. Also, DC air conditioners with 1.5 kW cooling capacity were used at the outdoor sites, while soft-start inverters of 5 kVA capacity were used for the indoor sites.
- Demonstration process: PV panels are installed adjacent to the shelter and lithium-ion battery systems and energy management systems are placed inside the shelter, enabling centralised remote monitoring and control. The outside of the shelter is coated with photocatalytic paint to reduce the indoor temperature.
- Role of photocatalytic paint: This paint has a high solar reflective index and is applied on the shelter’s external surfaces to keep the painted surfaces cool, thus saving energy.
India has a steep target of increasing renewable energy generation to 175 GW by 2022. Various renewable energy solutions with different technical merits can be considered for deployment at telecom tower sites to reduce the carbon footprint. With green energy becoming a key focus area for the country as a whole and for the ministries of environment, power, and new and renewable energy, a joint approach and clear directive encompassing all industrial sectors will ensure success. s
Based on a presentation by Tushar Kapadia, Vice-President, Strategic Initiatives, GTL Infrastructure Limited