IES Interview preparation notes – Power system (EE) – By Mr. Swayamdeep Singh , AIR 23 (ESE 2014)

Hello friends, here are the IES interview preparation notes on Power System by Mr. Swayamdeep Singh . If you have any doubts, you can ask in the comments below. I sincerely thank Swayamdeep for this voluntary contribution.

Hi, congratulations on qualifying for ESE interview. Here I am sharing notes on Indian power system which I prepared for interview.

You can find notes on

  1. Power theft
  2. Smart energy meters
  3. Challenges of power generation
  4. Rural electrification
  5. Solar power in India
  6. Smart cities and smart grids
  7. Some facts of Indian power sector , regional grids

Power Theft or pilferage

Pilferage is the theft of part of the contents of a package.

In 2010, electricity losses in India during transmission and distribution were about 24%, while losses because of consumer theft or billing deficiencies added another 10–15%

How power theft is done?

  • Tampering meter
  • Using unauthorised wire/ katiya to tap distribution feeder

Solutions –

  • Distribution by Cable connection (Underground distribution) : not possible to put unauthorised wire there
  • Report power theft on
  • Educate people about the effect of power theft on them . Tell them how they have to pay the for additional load created by power theft & power outages. And ask them to report about illegal connection
  • Smart meters

Smart meters

What is a smart meter?

It is used to measure electricity, remotely switch the customer’s power supply off and/or individual appliances based on demand response. It can remotely control electricity consumption to maximise energy efficiency and load balancing.

Smart meters consist of two units:

  1. the metering device, which is in the custody of the distribution or utility company
  2. a display unit that is at the consumer’s place.

Typical smart meters being deployed in India are capable of one way communication only as those with enhanced features cost more and it is a sensitive subject for consumers in this market.

How can smart meter curb power theft ?

For the distribution firms, the meters can detect unusually heavy demand, which may point to tapping of wires. This is particularly relevant in certain parts of India where petty theft of power is rampant and manual detection is difficult.

Smart meters can also be used to shut off service to households and commercial establishments that don’t pay their bills.

Initial indications from deployments globally indicate that putting in place monitoring systems such as smart meters prevents loss due to electricity theft. It can also lead to lower power consumption as consumers who were earlier using ‘free’ power reduce it and resort to using only as much as they can pay for legally.

Also smart meters ease the burden on customers who regularly pay bills by billing them very accurately and often less.

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Problems / Challenges of power generation

Distributed generation (DG) refers to power generation at the point of consumption.

Why DGs ?

Generating power on-site, rather than centrally, eliminates the cost, complexity, interdependencies, and inefficiencies associated with transmission and distribution

Coal based plant facing shortage of coal

Problems –

  • Improvement of mining techniques
  • Finding new coal deposits
  • Bad quality coal available in India => import coal => energy security problem

Hydro project


  • Rehabilitation controversy

Solution –

  • Give the home and employment guarantees to displaced people
  • Today we are building dam , in some time canals has to be constructed, and canal top solar project will be started => labour is required => there they will be employed
  • Important power project must be given environmental clearance

Indian nuclear projects


  • Activism since Fukishima disaster
  • Educate people about safety precautions used

Solution –

  • Get eminent personalities / scientists like APJ to talk to people about it

DG projects (Solar , etc)


  • Costly : because demand is less


  • Subsidization/ incentives for solar plants e.g. rooftop solar plants => demand increase, cost comes down
  • Later subsidies not be required
  • Homes which get rooftop solar plans should be provided with bidirectional meter. so that they can make money with surplus power

Rural electrification

Using microgrids for rural electrification

Microgrids are modern, localized, small-scale grids, contrary to the traditional, centralized electricity grid (macrogrid). Microgrids can disconnect from the centralized grid and operate autonomously, strengthen grid resilience and help mitigate grid disturbances. They are typically low-voltage AC grids, often use diesel generators, and are installed by the community they serve. Microgrids increasingly employ a mixture of different distributed energy resources, such as solar hybrid power systems, which reduce the amount of emitted carbon significantly.

e.g. read this quora answer –

Instead of just concentrating on big power plants which take years of planning to come up we can shift our concentration on small power plants of 1MW. Desi power makes cooperative society in village and for them small power plants are established. These biomass power plants use weeds like Daicha, Ipomia as fuel. Villagers are trained to run and maintain a power plant. Power is sold to the villagers at nominal margins of profit. Now there are many benefits of these power plants.

  1. They provide clean source of power to villagers and it can be built at very remote places where there is still no electric poles. ( I have worked on these places so I know the condition, villagers at these places use to travel 3 to 4 Kilometers to charge their cell phones).
  2. As power plants are built very close to villages so negligible distribution losses.
  3. Growth in power based industries in villages like lathe, welding machines, cold storage for agriculture products, rice mills.
  4. Due to exposure to this technology villagers become more aware of the opportunities. Evening markets grow, education increases.
  5. These small power plants give job to around 4 to 5 villagers directly and 10 to 15 indirectly. Villagers don’t depend on diesel gen sets for irrigation any more.
  6. Most important is that the dependency of these villagers on big power manufacturers decrease. They don’t need to wait for power anymore.

These are just few of the advantages. Its not necessary to have just biomass power plants. Solar power plants, Wind mills or hybrid systems can also be used as viable source of energy depending on the region.

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Solar power

  • India has recently announced target to install 100 GW solar power capacity by 2022
  • Many believed that the initial target of 22 GW by 2022 would be difficult to achieve, there is an increased optimism regarding the new target.
  • The government is set to push for ultra mega solar power projects with capacities of up to 4 GW
  • Small-scale projects that would cover thousands of kilometres of canals and millions of roofs are also catching up fast.
  • A number of states are considering implementation of net-metering regulations to increase adoption rates in the domestic sector.
  • Depend on the removal of bureaucratic hurdles,
    • availability of low-cost and sustained finance
    • attractive tariffs,
    • Bidirectional meter.

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Instead of protectionist measures, the Indian solar market needs to focus on mechanisms to attract private and international finance. Supporting domestic project developers and manufacturers through innovative finance options and international cooperation will be much more beneficial for the Indian solar sector, and the environment as a whole.

  • As the solar market matures, manufacturers and project developers can consolidate their efforts to achieve economies of scale.In the Indian solar market, one can expect that small, fragmented manufacturing utilities will consolidate to boost larger scales of production.

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Solar parks

Solar farms, or solar parks, are the large-scale application of Solar Photovoltaic (PV) installations used to generate electricity.

Gujarat Solar Park is the name used for a group of solar parks being constructed in Gujarat, India. This makes Gujarat as Asia’s largest solar park hub

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Canal-top Solar Power Plant

1 MW grid-connected Solar Power Plant at village Chadrasan, T: Kadi, Dist: Mehsana on Narmada canal is an engineering innovation as it serves the triple purpose –

  1. Generation of clean energy,
  2. Annually reducing 90,000 litres of water evaporation from the canal
  3. Use of precious land for the solar power plant.

Source- <>

Canal Top Solar Power Plant in Gujarat

Solar cities

What is a Solar City?

Several Indian cities and towns are experiencing rapid growth in the peak electricity demand. The local governments and the electricity utilities are finding it difficult to cope with this rapid rise in demand and as a result most of the cities/towns are facing electricity shortages. In this context, the “Development of Solar Cities” programme    is designed to support/encourage Urban Local Bodies to prepare a Road Map to guide their cities in becoming ‘renewable energy cities’ or ‘solar cities’.

The Solar City aims at minimum 10% reduction in projected demand of conventional energy at the end of five years, through a combination of enhancing supply from renewable energy sources in the city and energy efficiency measures. The basic aim is to motivate the local Governments for adopting renewable energy technologies and energy efficiency measures. In a Solar City all types of renewable energy based projects like solar, wind, biomass, small hydro, waste to energy etc. may be installed along with possible energy efficiency measures depending on the need and resource availability in the city.

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Smart cities

The key components of the planned smart city initiatives in India are :

  •  Smart parking systems
  •  Smart grids
  •  Smart health care systems
  •  Smart transportation systems
  •  Smart public safety systems

Apart from these, there are also plans of building smart systems for:

  •  Environment management
  •  Digital signage
  •  Urban lighting
  • Smart transportation system – which has the capability to track and send real-time mobile alerts to citizens if there is a block in any of the approaching roads.

In computing, real-time refers to a time frame that is very brief, appearing to be immediate. When a computer processes data at this speed, it reads and handles data as it is received, producing results without delay. For example, a website that is updated in real-time will allow its viewers to see changes as soon as they occur, rather than waiting for updates to be visible at some later date.

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  • Smart parking -Having a smart parking system which would direct a visitor on entry to a specific location where a parking slot is available.
  • Smart health care systems – A smart health care system which has a wearable device to monitor an aged citizen’s vital body parameters, such that doctors/ family members are alerted before hand when the parameters start showing signs of variation. This could eventually save many lives.
  • Smart public safety systems -Safety of women and children. One possible solution is to use CCTVs, wearable devices and mobile applications which can be used to alert police officials in case of any danger.

Internet of Things (IoT)

Underlying technology which forms the basis of these smart city initiatives is the Internet of Things (IoT).

IoT is at the forefront of the digital universe. It is a technology which is used to interconnect embedded objects / devices like sensors, mobile devices and so on, and facilitate communication among them without the need for any human intervention. IoT becomes very prominent in the present era where the number of internet-connected devices (12.5 billion) have surpassed the number of human beings (7 billion) on the planet in 2011.

The underlying business objective  for setting up smart cities in India is to create ac$15 billion ‘Internet of Things (IoT)’ industry in India in the next six years, thereby creating a host of new job opportunities in the country in various industrial sectors. IoT offers promising opportunities for telecom operators & system integrators

The creation of IoT-based platforms for setting up smart city initiatives is not an activity which can happen overnight. The first step for setting up an IoT platform is the creation of a proper digital infrastructure for India. In order to ensure this, the digital India programme has been launched. This programme aims at ‘transforming India into a digitally empowered society and knowledge economy’ and will also provide the required impetus for the development of the IoT industry in India

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Smart grid

A smart grid is a system which includes a variety of operational and energy measures including smart meters, smart appliances, renewable energy resources, and energy efficiency resources. Electronic power conditioning and control of the production and distribution of electricity are important aspects of the smart grid.

See this video –

It can be linked to thousands of power sources, including climate-friendly ones such as wind and solar. All of this instrumentation then generates new data, which advanced analytics can turn into insight, so that better decisions by key stakeholders of the value chain can be made in real time. The whole system can become more efficient, reliable, adaptive and smarter.

As appliances and other technologies align with a smart grid’s capabilities, consumers will also be able to create ‘home area networks’ of smart appliances, thermostats, security systems, and electronics that will ‘talk’ with the grid. For example, there is no need for the compressor or defrost unit of a refrigerator to operate during peak hours – it can wait. Today, millions of refrigerators that operate at random contribute to thousands of megawatts of peak-load. This can be controlled through simple modifications in the refrigerator. Very soon, most home appliances will become smart.

Consumers could get voicemail or email messages during a peak-energy-use time that encourages them to turn off certain appliances in return for financial incentives from utilities. Or there might be a setting on an appliance, such as a dishwasher, so that it would automatically run at a time when electricity demand is relatively low. These capabilities would allow consumers, companies and communities to save power and money. And ultimately this would result in lower levels of emissions of the greenhouse gases that contribute to climate change.

The design of a sustainable smart grid model would also provide a blueprint for developing nations. And the reduction in carbon emissions along with potential technological innovations would benefit all nations, developed and developing alike.

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Indian power sector

  • The utility electricity sector in India had an installed capacity of 278.733 GW as of 30 September 2015
  • Renewable Power plants constituted 28% of total installed capacity and Non-Renewable Power Plants constituted the remaining 72%.
  • India became the world’s third largest producer of electricity in the year 2013 with 4.8% global share in electricity generation surpassing Japan and Russia.
  • During the year 2014-15, the per capita electricity generation in India was 1,010 kWh with total electricity consumption (utilities and non utilities) of 938.823 billion or 746 kWh per capita electricity consumption

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McKinsey claims that India’s demand for electricity may cross 300 GW, earlier than most estimates. To explain their estimates, they point to four reasons:

  • India’s manufacturing sector is likely to grow faster than in the past
  • Domestic demand will increase more rapidly as the quality of life for more Indians improve
  • About 125,000 villages are likely to get connected to India’s electricity grid
  • Blackouts and load shedding artificially suppresses demand; this demand will be sought as revenue potential by power distribution companies

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Regional Grids of India

The Indian power system for planning and implementation is divided into five regional grids. Establishment of one unified grid through integration of regional grids was conceived by Central Transmission Utility in nineties. The work of integration took place in a sequential manner.

On October 1991, North-Eastern (NER) and Eastern (ER) grids were integrated. On March 2003, Western (WR) grid and NER-ER were interconnected. Next on August 2006, Northern (NR) and Eastern (ER) grids were interlinked, thereby forming a NEW grid i.e. Central grid. By the formation of this grid, it helped the 4 regions to meet their demand-supply mismatch.

Since there was a lack of integration of NEW grid with Southern (SR) grid, the Southern region remained as power deficit region in the country. As per Load Generation Balance Report for 2013-14 released by the Central Electricity Authority (CEA), Southern region had a power deficit of 26.1% in the year 2012-13. Though HVDC link exists between the NEW grid and SR grid, vast amount of power can’t be transferred, due to the fact that the HVDC link has a limited transmission capacity.

On 31st December 2013, Southern grid was connected to Central grid through the newly commissioned 765 KV Raichur-Sholapur transmission line thereby forming ‘One Nation-One Grid-One frequency’ system.

Grid failure of 2012

The July 2012 India blackout was the largest power outage in the world, occurring as two separate events on 30th and 31st July 2012. The outage affected over 620 million people i.e., about 9% of the world population, or half of India’s population, spread across 22 states in Northern, Eastern, and North-Eastern India. The main reason for this blackout was due to demand-supply mismatch. Since southern grid was not synchronized with central grid, it was not affected. This sort of a black out can be countered by the unified grid, if proper grid standards are maintained.

The three-member investigation committee consisted of S. C. Srivastava, A. Velayutham and A. S. Bakshi, and issued its report on 16 August 2012. It concluded that four factors were responsible for the two days of blackout:

You can go through the following links for info about HVDC system in India

Please point out if any error has crept in. Share your material after selection. All the best.

Swayamdeep Singh

AIR 23 ESE 2014 Electrical engineering

Thank you for reading. If you have any doubts, you can ask it here itself in the comments. Please share this post so that you can get even tougher competition during interviews. 😛

All the best 🙂


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