all of you, are well aware what is power system. So, we have to slightly see in deeper in about

its structure. Before we do that, we left last time about the diversity factor I think

we have to come up to day light saving we have talked about it.

Now, staggering of the office timings, now what is staggering of office timing? Suppose,

some offices start 8, some 9, some 10, it does happen in our country all offices do

not start at 9'o clock. What is the advantage? The advantage is manifold for example, if

you know that your office starts at say 11, why should you take bath at 6 you will I know

get up leisurely take bath. What has bath to do with your energy, because

you will start your geyser, so you are using energy at different times; hence diversity

factor will be help. Everybody in Delhi is not going to start his geyser or her geyser

at a same time. So, as I said for every activity that you do, you need electric energy, preparing

breakfast you need you know the toast or sandwich maker or mixie or microwave or whatever? So,

all these activities will take place at different times, because you have to get out of your

house at different times. Incidentally the bonus is ease of transportation

system. Imagine, if whole 1 crore leaves their houses at same time, do you have that transportation

system in place, the buses, you will not find any space, and there is no railway network

as yet. So, it helps to ease the transportation problem at least you will get a space to stand

in a bus; or even if you are taking your car out, you know there may not be a jam.

Different time zones, now what do you mean by different time zones? India is the country,

where there is only Indian standard time right from Kanyakumari it will Jammu and your Somnath

to Assam. But, please understand before partition, even Peshawar time was same as time as Delhi

time. Now, Pakistan is half an hour behind and Bangladesh is half an hour ahead I hope

all of you know this fact. So, why not we divide the remaining part of

the country what is India today into three parts. Let the western zone we have Pakistan

timing, let the eastern zone have the Bangladesh timing, and the central zone today's Indian

standard time; you may ask me questions, so what we happen, there may be more confusion,

well confusion would not be there, because people will be understand.

Now, the bus is going to Lahore they suddenly adjust their clocks, moment the reach Lahore

border. So, you will be adjusting your clock, moment you reach Ambala let us say the Ambala

time zone changes. But, what is the advantage? The advantage is instead of having 1 peak,

now you will have 3 peaks and smaller ones. So, you need not un necessarily have higher

install capacity you can do away with that, you need not add any extra capacity and whatever

capacity you have, that can be used more optimally. Because as you all know adding a mega watt

needs 4 crores, transmitting that mega watt needs another 4 crores that is today's price.

And where are crores in India, we do not we are a poor country we do not have money.

So, in order to avoid that capital investment, which government does not have; because by

enlarge, most of the power systems in India is being controlled by government of India,

there is hardly any private participation. Though, we desire we hope we request them

please come in and invest money. But, you know the Indian power system privatization

started and ended with Enron, Enron he was a sad story like your Devdass. So, people

do not want to repeat another Enron. So, it is a basically the duty of the government

to provide you power and they do not have money. So, why not use the existing power

system optimally and there, these different time zones will definitely help us. And mind

it as I said in the last lecture, all these measures do not need any money, they are free.

If you declare tomorrow will timings will change as you pass Ambala or Kanpur, you do

not have to pay anything, only thing you have to adjust your watches; as indeed you will

go do it when you abroad, when you go to US you adjust your watches to New York time's,

Delhi time would not be there. Then, the last item in this category of high

diversity factor is a two part tariff. What is tariff, when you go to hotel you ask what

is a tariff what, how much it will cost you if you stay for night. So, similarly, the

power you get in your home or industry or a commercial building, you to pay nothing

is free. So, there is certain tariff and in India the most popular tariff is two part

tariff. And two part tariff means, what? There is a charge for kilowatt there is charge for

kilowatt hour as we will see after some time the equation exact equation.

You should have an incentive to have better power factor, why better power factor? If

power factor is low, the P is equal VI cosine phi all of you know this equation, now power

factor is low voltage being constant, the current will go up to get the same value of

P this which mathematics everybody knows. Current going up is not good, it is bad. Why

it is bad? It will have more more losses I square r your conductor will get heat up,

your insulation may melt it may fail. So, our aim should be to have as much higher power

factor as possible. So, that is a part of power quality I am sure all of you must have

learnt a topic called power quality, now it is very important topic in under graduate

wherever you have done done your that the degree.

So, if power factor is high we say power quality is good. Another power quality issue is harmonics,

which you must have heard about T H D Total you know Harmonic Distortion, which should

be less than 5 percent; if you have done power electronics course or drives course in your

under graduate. Then I have two more factors given on this sheet, plant capacity factor,

plant use factor.

Now, these two factors are equally important as were the earlier two, the load factor and

diversity factor. What does the plant capacity factor convey its nothing but, a ratio any

factor is got to be a ratio, ratio of actual energy produced upon maximum possible energy

that could have been produced. In fact, you also have a study factor, the actual studies

carried out by you up on what you could have really done.

So, you should also try to use this factor in order to have better studies schedule or

program. This is in short can be written as a average demand up on installed capacity.

What is the use, if you have better plant capacity factor that means the existing plant

you are using optimally, you are using in a better way. See, you purchase a book 400

rupees and if you do not open it through out the semester, you have wasted your 400 rupees

if you get a scholarship; otherwise, you have wasted your 400 rupees of your parents or

whose ever is supporting you. Next is plant use factor, look the difference

between the two factors they are not otherwise, I would not have written them twice. Plant

use factor is nothing but, actual energy produced kilowatt hour upon plant capacity into time

the plant has been in operation. This is a maximum possible energy, here actually what

energy you could have generated, if you have used plant capacity. So, indirectly maintenance

is involved in it, indirectly how you are up keeping your power plant is your whole

plant capacity available or there is a d rated. What is rated? 100 mega watt unit in never

operated in 100 mega watt in India, it is rated to 80 mega watt; like, you people do

not do your work to the best of your capability you always do less than that, that is a rating

of yourself.

I was just talking about tariffs couple of minutes back the tariffs is back here, cost

of electric power nothing is free, there is no free as they say in management. So, if

you take a power otherwise it will be called theft, those of the person who use electricity

without paying that is nothing but, a power theft.

In fact, in our country, theft is one of the highest 40 percent of the power is you know

used are not paid for; and that is why T N D the part of your title of your course is

renamed as theft and dacoity, not transmission and distribution, which is very unfortunate.

And every person is trying to reduce this theft, power theft.

Now, the cost of electric power is given by a plus b kilowatt plus c kilowatt hour, what

are a b c, this three are coefficients all of you have done enough mathematics to understand,

what is coefficient; a is constant is a fixed charge like, telephone whether you make a

single call or not, you have to pay that 250 rupees rent. And that is why people are going

more and more for mobile phone, because there is no rent there, if it is a prepaid, they

already cut whatever they want to cut. Plus b time's kilowatt, b is proportional to maximum

demand, as c is the units actually consumed. So, all of you must be paying electricity

bill or your parents must be paying electricity bill at home. So, that bill will give you

one is a fixed charge then depending on what is your connected load in your house; when

you get connection, you have to declare what is your connected load, and then the actual

energy consumed, which energy meter shows. Unfortunately in this country, all auto taxi

meters are fast all energy meters are slow. In fact, some of the energy meters run in

opposite direction in night. So, that by the time morning is there, you are back to the

starting point. Now, this should influence the load curve and load factor. Now, if load

factor is low, there should be penalty on the consumer. How do you...? By replacing

kilowatt to K V A; what is k v a kilowatt into cosine 5 power factor. So, rather having

a kilowatt, let us have k v a and then, the consumer will be careful in having a better

power, you will be forced to have a better power factor.

So, he has to install power factor corrective devises, this is what people do in energy

audit, I am sure you must be doing that energy audit course. Have you are you doing there,

evening people have a compulsory 1 unit energy audit course; and I request you to go and

sit there. Because, there are some courses which are not there for the morning students

which is bad? So, you can go and nobody will say no, everybody

is welcome please do that energy audit course. What is energy audit, you have to go and see

in any any premises whether it is a factory, whether it is a building, whether it is a

restaurant; how the energy is being consumed, in what energy is being consumed; is it being

consumed rightly, is the bulb not required 100 watt in 50 watt will do, is it being even

the house keeping measles to improve. Then you know the energy c is to keep your

things clean you do not have to wait for Diwali to clean your bulb. It can be cleaned regularly

and will find the difference the lumens coming out will be much more than normally you get.

So, this is what we do. You have to see the why voltage is coming down, why not we have

a voltage stabilizer, the power factor. How do you improve power factor, just by putting

capacitances in shunt with load, the power factor will be go up. No doubt, there is a

cost further capacity, there is a price to pay, but it is worth; because there is a something

called payback period, you invest 10 rupees and that 10 rupees you will realized back

in no time; and the payback period will be few days or months or at the most a year,

it is worth. Other things are S V S etcetera Static Var System. fax I do not know how many

of you know FACTS Flexible AC Transmission System. So, all these things are come here

to have three in one. They not only improve power factor, they improve

efficiency and they improve the voltage control, voltage stability is you know achieved. What

is the optimization problem here, what is problem here, what is the problem here, compensation

how much where when, if you answer these three that is your R and D topic.

Now, there are five examples solved in the book 1.1 to 1.5, please go through these five

examples. If you have any difficulty in understanding them, if necessary we will have a separate

class for this, if not, because they are solved. you should how do you read a solved example,

how do you solve a solved example, that is also an art; do not read it like a novel or

a magazine, read the problem close the book try to solve it yourself, because we have

already covered a theory. The beauty is why do you why should you solve

the solved this problems, you know exactly where you have gone wrong; in an unsolved

problem, you would not be able to know where you have gone wrong, only thing you come to

know is the answer is wrong. But, why answer is wrong it is not so easy to find out, you

have to consult your colleague who should be solving it independently. And if you do

that same mistake, again there is a problem you never come to know where you have gone

wrong. So, the solved examples of very important,

please go through them solve them yourself independently; and let me know whether you

you have solved them or was the is there any difficulty you please let me know. What is

load forecasting, it is a very important topic today. You must be seeing weather forecast

every day whatever channel you may tune for I do not whether present day students at all

see anything other than m TV and v TV. But, if you care to see any news channel, then

there will be a weather forecast, even Doordarshan also shows 4 megacity temperatures, now a

day they have started giving other city temperatures also.

Now, any planning will need this load forecast, you are planning a power system for 15 years

hence, for the India of 2020 what should we know? We should know several factors, what

we will be the population, what what will be the industrial scene, how much agriculture

will be there, how much houses will use electricity. Today only 85 percent villagers have been

15 percent are not. And these 15 percent are places in accessible places hilly areas, there

is no grid there. So, are we able to take grid up to that point or not, we have to plan

all these things. Power plants, once you know the load, then only you will go for power

plant. How what do you do when you go for a market; suppose, your mother or father tells