Greentech Lead India: Electricity demand in India has been consistently outstripping its generation over the years. Fuelled by a healthy GDP growth rate and growing access to power in rural areas, electricity consumption in the country has grown at a CAGR of ~ 6% , resulting in a peak load deficit of around 10%.
As on October 2012, the installed power generation capacity in India stood at 209 GW with thermal power (comprised of Coal, Oil and Gas) accounting for ~ 66% of the installed base. India’s fuel mix for power generation has been traditionally biased towards coal. However, continuously rising demand for coal over the years coupled with problems related to land acquisition and resistance to coal mining has made it increasingly difficult to get long term coal linkages.
As per estimates made by the International Energy Agency (IEA) in its World Energy Outlook for 2030, India will need an additional power generation capacity of about 350 GW by 2030. Under such circumstances, India will be forced to reduce its dependency on coal and the non –conventional energy sources will have to play an important role in the country’s emerging energy mix.
Development of Renewable Energy (RE) in India
Non-conventional energy sources account for ~11% of India’s power generation capacity. Renewable energy projects have been primarily focused on Wind power, which constitutes about 70% of the installed capacity. One of the key drivers for this has been the financial incentives provided by the government for development of wind power projects.
Why RE projects have not picked up in India
Considering the limited scope of this article and predominance of wind energy in India’s renewable energy portfolio, we will restrict our discussion to analyzing issues pertaining to wind power projects.
The Ministry of New and Renewable Energy (MNRE) has introduced several policy and regulatory changes for promoting RE projects. However, their success has been limited due to:
Lack of integrated policy
Financial incentives and tax exemptions being doled out by the government towards capital expenditure for setting up of RE projects had turned it into a financial instrument rather than a sustainable source of power generation. The developers put up the required infrastructure but never bothered to run them efficiently. There was limited focus on developing a strong supplier base for equipments, facilitating earning of carbon credits and supporting R&D initiatives focused on renewables
Volatile energy supply
The unpredictable nature of renewable energy sources makes it difficult for the Utilities to rely on them for meeting their base load requirements. The utilities require that the wind farms should have systems which are capable of regulating voltage and reactive power to maintain a smooth voltage profile at the point of grid connection. They should not trip due to grid faults and must be able to withstand occasional electromechanical swings in the power grid.
Such capabilities require investments in power forecasting solutions and latest technologies for Wind Turbine Generators (WTGs). Due to the fragmented ownership of wind farms in India, where individual investors typically own a few turbines rather than an entire wind farm, nobody is willing to make these upfront investments, thereby leaving the turbines isolated and its potential under-utilized.
Electricity grid management
Power system Operation Corporation (POSOCO), a subsidiary of Power Grid Corporation of India is responsible for managing the stability of national as well as regional electricity grids and their interconnection. POSOCO needs a clear visibility of the available power generation capacity in order to plan the day-ahead generation and evacuation schedule. Any deviation from the schedule, if undetected, could cause power swings and grid frequency instability which may even lead to blackouts. Therefore, without the support of suitable technology solutions for integration of renewable energy resources, the grid operators find it difficult to ensure efficient and reliable grid management.
Promoting “Green energy” and its integration with the grid – The way forward
Policies for market development
There is a need to define a comprehensive strategy for the development of entire eco-system around renewable energy. Apart from incentivizing capacity addition, focus on market development is required through increased adoption of schemes like Generation Based Incentives (GBI), Renewable Purchase Obligation (RPO) and Renewable Energy Certificate (REC) trading. Some of these have already started. We also need to invest in developing the required technology infrastructure in the country so that RE projects become economically viable and self-sustainable
Adoption of Technology solutions
There is a need to integrate the advancements in Information technology and automation solutions with the fundamentals of Electrical engineering to develop innovative digital solutions which would overcome the limitations of traditional electricity supply. Some of these solutions have been briefly discussed here
Wind power forecasting
Central Electricity Regulatory Commission (CERC) has mandated forecasting of wind power generation by the wind farms with an accuracy of at least 70%. Those who do not comply will have to pay Unscheduled Interchange (UI) charges. Accuracy of the forecasting package will depend on the span of its automation controls and its ability to integrate various solution components. Indian wind farm operators are not exposed to such sophisticated forecasting solutions and rely on software packages which have limited capability.
In the figure below Infosys has proposed the conceptual architecture for a robust wind power forecasting solution:
Wide Area Monitoring System (WAMS)
Power system operators rely on real time data, communication, computations and control for efficient management of the electricity grid. Currently these functionalities are provided by SCADA (Supervisor Control and Data Acquisition) system. WAMS is an emerging solution which uses Phasor Measurement Units (PMUs) for real time measurement of voltage-current phasors and time stamping them using a GPS clock. These measurements are then aggregated and time aligned using a Phasor Data Concentrator (PDC) to get a view of the transient state of the grid and study its dynamic behavior.
The repository of data collected from various PMUs installed at multiple points in the grid could be analyzed to gain useful insights
- Event analytics – post disturbance analysis of event to identify triggers and root cause
- Real time analytics – to monitor transient state power oscillations, harmonics etc
- Predictive analytics – to predict system behavior based on complex algorithms and historical data models
Adoption of WAMS by the grid operators would enable them to effectively monitor the grid operations in real time and make near accurate “state estimations” using various ‘BIG DATA” analytics techniques. Improved control over grid operations would encourage the system operators to allow seamless integration of renewable energy sources with the electricity grid.
In the figure below Infosys has proposed the conceptual architecture for PMU based integration of renewable energy sources
Solution architecture for PMU based integration of renewable energy sources
Conclusion
India’s pursuit to increase the share of renewable energy sources in its total power generation as mandated by the National Action Plan on Climate Change (NAPCC) is contingent upon implementation of technology solutions for seamless integration of renewable energy sources into the electricity grid. Some of the key technology interventions which could help us reach our goal are
- Wind power forecasting solution – its implementation needs to be mandated for all the wind farms so that the volatility associated with wind power generation is minimized and we have a reasonable estimate of the day-ahead power generation schedule
- Wide Area Monitoring System (WAMS) – Phasor measurement units to be installed at critical points in the grid for real time monitoring of grid performance parameters. Any deviation from the expected behavior could be instantaneously captured and correction actions taken suitably
- Smart Grid – Advanced Metering Infrastructure (AMI) and Distributed Generation Integration – would enable bi-directional communication between the customer and the Utility for better alignment of the energy consumption and generation volumes at small scale (household) as well as bulk scale
Authors:
Sachin Sinha, senior associate consultant with Energy and Utilities practice of Infosys
Mitul Thapliyal, principal consultant with Energy and Utilities practice of Infosys