Green Grid

Power Grid Corporation of India Ltd., in conversation with the editor, affably offers insights on issues of sustainable grid management and outlines mechanisms to increase grid efficiency. Optimistic about the sustainability of India’s energy scenario Shri Chaturvedi feels that renewable energy will take great strides in the near feature.

What are the chief objectives of a green grid and how have these objectives been achieved in the Indian context?
POWERGRID, one of the largest power transmission utilities in the world, have had minimal environmental and social impact in its developmental activities owing to the very nature of its activities that does not involve disposal of any pollutant in land, air or water or any large scale excavation resulting in soil erosion. However, to achieve the goal of sustainable development, and conservation of natural resources, POWERGRID has adopted a proactive approach and developed a comprehensive Environmental Social Policy and Procedures (ESPP) in 1998 through extensive national consultations. The basic principle of the ESPP is avoidance, minimisation and mitigation.

Avoidance: There has been a tremendous reduction in forest involvement in implementation of transmission lines. For example, forest involvement which was about 6 per cent in 27,000 circuit kms of lines till 1998 has come down to 2 per cent with proactive and systematic conservatory approach adopted in construction of 20,500 circuit km line during the last 6 years.

Minimisation: The Corporation is developing compact substations to minimise land requirement and has been trying to locate substations on Government land to minimise the social impact. Provision for rain water harvesting and collection of used/waste water for conservation has been undertaken at several locations. Also, the adoption of innovative tower design like multi-circuit and tall towers to protect wildlife and trees in ecologically sensitive areas have reduced felling load. In fact the felling along Tehri transmission line was reduced to 14,739 against earlier estimate of 90,000 trees in Rajaji National Park due to installation of 85m high towers.

Mitigation: Massive plantations are being carried out at sub-stations. Measures like compensatory afforestation involve plantation over twice the area affected by the project. POWERGRID has contributed about 110 crores to state forest authorities towards afforestation on more than 10,000 hactares of land over the last decade. Further, POWERGRID has developed a robust transmission system and inter-regional links. This has facilitated the evacuation of green power from wind and hydro which substitute fossil fuel based power generation and thereby helps in minimising CO2 emission.

Is India working on a Smart Grid or an Intelligent Grid?
A Smart Grid envisages being able to heal itself, motivate consumers to actively participate in operations of the grid, provide higher quality power that will save money wasted from outages, accommodate all generation and storage options and enable electricity markets to flourish. To achieve these objectives, efforts are underway at all levels - generation, transmission and distribution sectors. Use of renewable sources in generation, use of wide area monitoring system (WAMS) and software application tools SCADA/EMS in transmission, and use of distribution automation and smart meters in distribution are some of the key issues in the implementation of Smart Grid.

POWERGRID’s initiatives in the implementation of Smart Grid projects:

• Pilot project for installation of Phasor Measurement Units (PMUs) in the
Northern Region

• Implementation of intelligent monitoring and control of the interconnected electric power grid using WAMS
In order to develop advanced software functions, POWERGRID has taken up a project in the Western Region, under the New Millennium India Technology Leadership Initiative (NMITLI) programme. The main features of the project are the installation of PMUs at 25 to 30 locations mostly in Western Region Grid and development of software functions using PMU data for better visualisation and situational awareness. This will be followed by similar projects in other regions and the coverage shall be gradually increased to encompass the entire national grid. It is expected that in next 5 to 7 years, the entire network will be covered by Smart Grid technology.

Tamil Nadu has a sizable amount of power being generated from wind. Is the power fed into the grid by the above State and others such as Maharashtra and Rajasthan which also have a large number of wind power installations?
India has one of the largest programme in renewable energy covering a wide spectrum of resources such as wind, solar, biomass, small hydro etc. Out of these programmes, the highly successful India’s wind power programme is entirely market driven. India ranks amongst the top 5 countries in the world with an installed capacity of more than 10,000 MW.

Capacity in MW
Tamil Nadu : 4304.5
Maharashtra : 938.9
Gujarat : 1566.5
Karnataka : 1327.4
Rajasthan : 738.4
Madhya Pradesh : 212.8
Andhra Pradesh : 122.5
Kerala : 27
West Bengal : 1.1
Total : 10242.3
Data as on 31.3.2009

Is solar power also fed into the grid?
As the cost of solar power installations is very high, Rs 15 to 20 crores/MW, solar power fed into the grid is very small (only about 2 MW). The government has taken a number of initiatives and has announced a new initiative on development and demonstration of megawatt capacity grid interactive solar power generation in January 2008 with a view to harness the vast solar energy potential in the country for power generation.