ABOUT PPCL

* The Puducherry Power Corporation was incorporated with the  objective of generating 32.5 MW of Electricity (22.9 MW from Gas Turbine and 9.6 MW from Steam Turbine) at Karaikal which is one of the outlying regions of Puducherry .The required gas is obtained from the Gas wells at Narimanam in the Cauvery basin under an agreement with the Gas Authority of India. The Corporation had received the entire cost of Rs. 133.04 crores as Share Capital from the Govt. of Puducherry till 1999-2000 and the same has been utilized for the execution of the Project.

* The first and prestigious gas based power plant was set up at T.R. Pattinam, Karaikal to cater to the power demand of Karaikal region. The plant on Open Cycle (22.9 MW Gas Turbine) was synchronized during October 1999. The plant was dedicated to the nation by the Hon'ble Prime Minister  of India on 25.05.1999.

* The plant was put into commercial operation w.e.f 3rd January 2000. The entire power generated from the Karaikal Gas Power Plant is supplied to the Electricity Department, Karaikal. The plant is performing extremely well till date.

* The power generated  by both the gas and steam turbines are distributed at 11 KV legal and distributed to local industries and consumers. Some of the power is exported to 110 KV level to nearby 110 KV substation.

* In consideration with the requirement of power in the Union Territory of Puducherry more so at Karaikal, expansion plans are in the anvil depending on firm allocation of gas of 4.85 lakhs cu.m per day for additional 100 MW, by the Ministry of Petroleum and Natural Gas.

                                    

FUNCTONS & OBJECTIVES (In Points and Specific)

 The main objectives besides others of forming the corporation are given below;

            a) To carry on the business of electric power generation and to construct, lay down, establish, operate and maintain generating stations and tie lines, sub-stations and main transmission lines connected therewith; to operate and maintain such generating stations, tie lines, sub-stations and main transmission lines as are assigned to it by the competent government and to fix and carry out all necessary power stations, cables, wires, lines, accumulators, lamps, works and to generate, accumulate, distribute and supply electricity and to light cities, towns, street docks, markets, theatres, buildings and places both public and private

            b) to construct, carry out, maintain, improve, manage, work and control and superintend any reservoirs, water works, tanks, dams, weirs, bridges and works in connection therewith, hydraulic works, electrical works and factories and other works and conveniences which may directly or indirectly contribute to subsidize or otherwise aid or take part in such operations.

          c) To carry on the business of mechanical engineers, manufacturer of all types of combustion engines, including oil and petrol engines, gas turbines, steam turbines, boilers, locomotives, road rollers, automobiles, trucks, tractors, agricultural implements and pumps.

          d) To carry on any consultancy works including planning, designing, erection, testing commissioning and maintenance in respect of the works relating to energy and power sector.

COMMITTEES

 

i)  Audit Committee

            An Audit Committee comprising of 4 members of the Board of Directors of the Corporation as required u/s 292 A of the Companies Act, 1956 has been constituted. This committee goes into the details of the Corporation in regard to the Financial reports, Audit Reports of the Statutory Auditors, AG and such other matters as the Board may authorize the Audit Committee to decide.

ii) Safety Committee 

           Safety Committee takes the responsibility to identify any safety defects that might be present in the Plant and explore their remedial measures to create a safe environment for the plant personnel.

ACHIEVEMENTS (SCHEMEWISE / ITEMWISE, YEARWISE)

A.  Physical Achievements :

   The Corporation is on the top in respect of Capacity Utilization of the plant in the country from the year 2000-01 as per the "Review of Thermal Power Station" brought out by CEA.

Sl.No. YearGeneration

(MU)

Generation Target fixed by Ministry of Power

PLF+ Target fixed by the Ministry of Power (%)

PLF (%)

1. 2000-01 234.13 230.00 80.79 82.23

2. 2001-02 249.35 235.00 82.54 87.73

3. 2002-03 264.00 235.00 82.54 92.48

4. 2003-04 275.42 255.00 82.32 96.74

5. 2004-05 275.41 255 89.87 96.74

6. 2005-06 258.38 250 87.81 90.74

7. 2006-07 270.60 260 91.32 95.05

8. 2007-08 273.62 260 91.07 95.85

9. 2008-09 257.45 250 87.81 90.43

The Operational Efficiency of the Plant. The Plant has surpassed the generation  target by the Ministry of Power, Government of

India consistently since commercial production. The target fixed for the current year 2008-09 is 250. MU.

B. FINANCIAL AND OTHER NOTEWORTHY ACHIEVEMENTS:

Year

 Profit after Tax

(Rupees in Crores)

Dividend Declared (Rupees in Crores)

 

% of Dividend

 

2000-01 6.40 0 0

2001-02 7.32 1.46 20%

2002-03 8.34 0.83 10%

2003-04 14.34 1.72 12%

2004-05 10.74 0.86 8%

2005-06 8.89 2.04 25%

2006-07 11.52 2.30 25%

2007-08 11.52 5.02 50%

2008-0911.66(un

audited)- -

* The Plant was dedicated to the Nation by Shri Atal Bhihari Vajpayee, the then Hon'ble Prime Minister of India on 25.05.1999.

* The Plant achieved the highest Plant Load Factor of 103.58%  during January 2003 and the yearly Plant Load Factor of 96.74% in 2004-05.

* The Corporation  received the National Safety Award for 2003 for outstanding performance in industrial safety as runner-up during the year 2003 in achieving lowest average frequency rate from Labour Minister, Govt. of India on September 21st 2004.

* The Corporation has contributed to Puducherry Chief Minister Relief Fund (viz) Tsunami Relief Fund- Rs.2.00 Crore in the year 2004-05 and Flood Relief Fund Rs. 5.00 Lacs in the year 2005-06. Contribution to Karaikal Carnival 2006- Rs. 4.00 Lakhs.

 

FINANCIAL EXPENDITURE 

            The Corporation had not received plan funds from the year 2000-01 and the entire expenditure is met from the revenue received from the sale of power.

Year Plan Expenditure (Rs. Lakhs)

1999-2000 190.00

2000-2001 to Till date Nil

DAILY GENERATION REPORT

       DATE

GENERATION DURING THE DAY IN KWH  

MAX. GENERATION DURING THE DAY IN MW  

CUMULATIVE GENERATION FOR THE MONTH IN MKWH

CUMULATIVE GENERATION FROM FIRST APRIL IN MKWH

26/05/2010

612500 25.52 15016510 31413840

25/05/2010

626970 26.12 14404010 30801340

24/05/2010

621740 25.91 13777040 30174370

23/05/2010

621960 25.92 13155300 29552630

22/05/2010

600100 25.00 12533340 28930670

21/05/2010

576730 24.03 11933240 28330570

20/05/2010

575540 23.98 11356510 27753840

19/05/201 591730 24.66 10780970 27178300

0

GAS COMPRESSOR

An essential component in any gas plant or gas system, a gas compressor is a mechanical tool designed to raise the pressure of gas or vapor. The increase in the pressure of the gas is done by lowering its volume. It is very natural that compression of a gas increases its temperature. Gas compressors are widely used in various industrial applications. It is one of the most essential as well as an expensive piece of equipment and has a predominant influence on gas processing in gas plants.

Working Principle

The working of gas compressor is similar to pumps. Both pumps and compressors increase the pressure on a fluid/gas and both are used to transport the fluid/gas through a pipe. However, as gases are compressible, the gas compressor can also reduce the volume of a gas which is not the case with pumps. Since liquids are relatively incompressible, the main purpose of a pump is simply to transport liquids and that brings out the difference between compressors and pumps. A gas compressor reduces the volume of a gas and this is done by pressing the gas molecules close together and storing them under pressure. The energy caused by this action allows the temperature of the gas to rise.

Reciprocating compressors:

A positive displacement compressor, reciprocating compressor takes successive volumes of air, which is confined within a closed space, and raising this air to a higher pressure. This is done by using a piston. Air is drawn into the cylinder through the piston's compressing and displacing element. This compressor is considered single acting when the air compression is done by using one side of the piston and when both the sides are used, the reciprocating compressor is considered double acting

THE THERMODYNAMIC CYCLE

An explanation of a few basic thermodynamic principles is necessary to understand the science of reciprocating compressors. Compression occurs within the cylinder as a four-part cycle that occurs with each advance and retreat of the piston (two strokes per cycle). The four parts of the cycle are compression, discharge, expansion and intake. They are shown graphically with pressure vs. volume plotted in what is known as a P-V diagram (Figure 3).

Figure 3. Intake

At the conclusion of a prior cycle, the piston is fully retreated within the cylinder at V1, the volume of which is filled with process gas at suction conditions (pressure, P1 and temperature, T1), and the suction and discharge valves are all closed. This is represented by point 1 (zero) in the P-V diagram. As the piston advances, the volume within the cylinder is reduced. This causes the pressure and temperature of the gas to rise until the pressure within the cylinder reaches the pressure of the discharge header. At this time, the discharge valves begin to open, noted on the diagram by point 2.

With the discharge valves opening, pressure remains fixed at P2 for the remainder of the advancing stroke as volume continues to decrease for the discharge portion of the cycle. The piston comes to a momentary stop at V2 before reversing direction. Note that some minimal volume remains, known as the clearance volume. It is the space remaining within the cylinder when the piston is at the most advanced position in its travel. Some minimum clearance volume is necessary to prevent piston/head contact, and the manipulation of this volume is a major compressor performance parameter. The cycle is now at point 3.

Expansion occurs next as the small volume of gas in the clearance pocket is expanded to slightly below suction pressure, facilitated by the closing of the discharge valves and the retreat of the piston. This is point 4.

When P1 is reached, the intake valves open allowing fresh charge to enter the cylinder for the intake and last stage of the cycle. Once again, pressure is held constant as the volume is changed. This marks the return to point 1.

Comparison of Gas Compressors

Item Reciprocating Rotary Vane Rotary Screw CentrifugalEfficiency at full load

High Medium-Low High High

Efficiency at part load

High due to staging

Poor-Below 60% at full load

Poor-Below 60% at full load

Poor-Below 60% at full load

Efficiency at no load (power as % of full load)

High (10%-25%) Medium (30%-40%)

High-Poor (25%-60%)

High-Medium (20%-30%)

Size Largetab Compact Compact CompactNoise level Noisy Quiet Quiet (when

enclosed)Quiet

Vibration High None None NoneOil Carry Over Moderate Low-Medium Low LowPressure Medium-Very

highLow-Medium Medium-High Medium-High

Capacity Low-High Low-Medium Low-High Medium-High

Applications of Gas/Air compressors

Fuel Gas / Power Generation Gas Boosting Gas Generation / PSA Gas Liquefication / Cryogenics Gas Transmission / Delivery

Oil Refining / Chemical Processing Refrigeration / Gas Drying Semiconductor Processing

Vessel / Cylinder Filling

GAS TURBINE

A Little Background

There are many different kinds of turbines:

← You have probably heard of a steam turbine. Most power plants use coal, natural gas, oil or a nuclear reactor to create steam. The steam runs through a huge and very carefully designed multi-stage turbine to spin an output shaft that drives the plant's generator.

←← Hydroelectric dams use water turbines in the same way to generate power. The turbines

used in a hydroelectric plant look completely different from a steam turbine because water is so much denser (and slower moving) than steam, but it is the same principle.

← ← Wind turbines, also known as wind mills, use the wind as their motive force. A wind turbine

looks nothing like a steam turbine or a water turbine because wind is slow moving and very light, but again the principle is the same.

A gas turbine is an extension on the same concept. In a gas turbine a pressurized gas spins the turbine. In all modern gas turbine engines the engine produces its own pressurized gas, and it does this by burning something like propane, natural gas, kerosene or jet fuel. The heat that comes from burning the fuel expands air, and the high-speed rush of this hot air spins the turbine.

Gas Turbine Engines Working

Gas turbine engines are, theoretically, extremely simple. They have 3 parts:

← A compressor to compress the incoming air to high pressure.

← A combustion area to burn the fuel and produce high pressure, high velocity gas. ← A turbine to extract the energy from the high pressure, high velocity gas flowing from the

combustion chamber.

The following figure shows the general layout of an axial-flow gas turbine - the sort of engine you would find driving the rotor of a helicopter, for example:

In this engine air is sucked in from the right by the compressor. The compressor is basically a cone-shaped cylinder with small fan blades attached in rows (8 rows of blades are represented here). Assuming the light blue represents air at normal air pressure, then as the air is forced through the compression stage its pressure and velocity rise significantly. In some engines the pressure of the air can rise by a factor of 30. The high-pressure air produced by the compressor is shown in dark blue.

This high-pressure air then enters the combustion area, where a ring of fuel injectors injects a steady stream of fuel. The fuel is generally kerosene, jet fuel, propane, or natural gas. If you think about how easy it is to blow a candle out, then you can see the design problem in the combustion area - entering this area is high-pressure air moving at hundreds of miles per hour. You want to keep a flame burning continuously in that environment. The piece that solves this problem is called a "flame holder", or sometimes a "can". The can is a hollow, perforated piece of heavy metal (shown here is half of the can in cross-section):

The injectors are at the right. Compressed air enters through the perforations. Exhaust gases exit at the left. You can see in the previous figure that a second set of cylinders wraps around the inside and the outside of this perforated can, guiding the compressed intake air into the perforations.

At the left of the engine is the turbine section. In this figure there are two sets of turbines. The first set directly drives the compressor. The turbines, the shaft and the compressor all turn as a single unit:

At the far left is a final turbine stage, shown here with a single set of vanes. It drives the output shaft. This final turbine stage and the output shaft are a completely stand-alone, freewheeling unit. They spin freely without any connection to the rest of the engine. And that is the amazing part about a gas turbine engine - there is enough energy in the hot gases blowing through the blades of that final output turbine to generate 1,500 horsepower and drive a 63 ton M-1 Tank! A gas turbine engine really is that simple.

In the case of the turbine used in a tank or a power plant, there really is nothing to do with the exhaust gases but vent them through an exhaust pipe, as shown. Sometimes the exhaust will run through some sort of heat exchanger either to extract the heat for some other purpose or to preheat air before it enters the combustion chamber.

The discussion here is obviously simplified a bit. For example, we have not discussed the areas of bearings, oiling systems, internal support structures of the engine, stator vanes and so on. All of these areas become major engineering problems because of the tremendous temperatures, pressures and spin rates inside the engine. But the basic principles described here govern all gas turbine engines and help you to understand the basic layout and operation of the engine.

OTHER VARIATIONS

Large jetliners use what are known as turbofan engines, which are nothing more than gas turbines combined with a large fan at the front of the engine. Here's the basic (highly simplified) layout of a turbofan engine:

 

You can see that the core of a turbofan is a normal gas turbine engine like the one described in the previous section. The difference is that the final turbine stage drives a shaft that makes it's way back to the front of the engine to power the fan (shown in red in this picture). This multiple concentric shaft approach, by the way, is extremely common in gas turbines. In many larger turbofans, in fact, there may be two completely separate compression stages driven by separate turbines, along with the fan turbine as shown above. All three shafts ride within one another concentrically.

The purpose of the fan is to dramatically increase the amount of air moving through the engine, and therefore increase the engine's thrust. When you look into the engine of a commercial jet at the airport, what you see is this fan at the front of the engine. It is huge (on the order of 10 feet in diameter on big jets), so it can move a lot of air. The air that the fan moves is called "bypass air" (shown in purple above) because it bypasses the turbine portion of the engine and moves straight through to the back of the nacelle at high speed to provide thrust.

A turboprop engine is similar to a turbofan, but instead of a fan there is a conventional propeller at the front of the engine. The output shaft connects to a gearbox to reduce the speed, and the output of the gearbox turns the propeller.