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Home assignments

Students who have not yet completed the home assignments can do that together with either EG2200 or EG2205. Please refer to the examination instructions on the front page for further details.

Lärare Mikael Amelin skapade sidan 19 december 2012

Lärare Mikael Amelin ändrade rättigheterna 19 december 2012

Kan därmed läsas av alla och ändras av lärare.
kommenterade 21 januari 2013

Hi,
there are some problems in Home Assignment I that are somewhat unclear. I hope we could get some clarities around these matters as they might be troubling other students aswell.
Problem 1: Are we looking for one common nordic electricity price? Or one electricity price per country, i.e one for Sweden and one for Denmark?
Problem 5: Do we consider the same variable operation cost for the fifth nuclear power plant than for those that have already been built in Finland?
Problem 6: Is the total nordic consumption increased by 2.5% or is it only Finlands consumption that is increasing? (The question seems to refer to problem 5, thus the confusion)

Thanks in advance

Daniel Brodén

Anmäl missbruk
Lärare kommenterade 22 januari 2013

Problem 1: We are assuming that Sweden and Denmark has a common electricity market. Would it then be possible to have different electricity prices in Sweden and Denmark?

Problem 5: This question is about making a rough estimate; therefore, you can pick any variable operation cost within the price interval for the existing nuclear power plants.

Problem 6: It is the total Nordic consumption that increases by 2.5%.

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kommenterade 23 januari 2013

Hi, while working with Problem 3 in the matlab program I encountered a few problems: 

While computing the price for a dry year (as stated in the question) no price is given, instead the program calculates that there is a lack of energy because the supply side cannot reach the demand. Is this a programming error?  However there is a line called Extra Import with values that ranges from 0 to 4.5 TWh depending on countries. Is the point that these numbers should be changed based on the information in Table 1 (as reffered to in the question) in order to import enough to satisfy the demand? 

When calculating the energy left to import, should we add the numbers in the row called Extra Imports to the total imports? (as the numbers in this row must come from the cables in Table 1?)

Thank you

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Lärare kommenterade 24 januari 2013

There are several ways to determine the need for import to the Nordic countries during a dry year. Choose the one you like best.

Anmäl missbruk
kommenterade 25 januari 2013

Hej!

I am a master student who has already finished the course of EG2050. Now I would like to re-take the course. Can I submit the reports, but only to finish the questions of bonus part and not attend presentations because right now I am still in Västerås for my master thesis?

Sorry for the late question and thank you for your kind help in advance!

Regards,

Mvh

Anmäl missbruk
Lärare kommenterade 25 januari 2013

Yes, that is ok.

Anmäl missbruk
kommenterade 30 januari 2013

Regarding Home Assignments Part II.

In problem 10 are we to find one common frequency or different frequencies for each area? 

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Lärare kommenterade 1 februari 2013

We want you to state the frequency in each area. Whether or not the frequency is the same in several areas is for you to determine. (Hint: How many synchronous grids are there in the system?)

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kommenterade 1 mars 2013

Hi,

I have a question regarding the bonus assignment 20 of homework 4. When simulating with the ppc.m script for a segment size of 70-75 I get unconsistent results on ETOC, LOLP and EENS. Otherwise the trend I notice is that my ETOC decreases with decreasing segment size and my LOLP increases. I guess my question is why do we suddenly get a total different phenomena when setting the segment size to 75?

Thanks in advance

Anmäl missbruk
Lärare kommenterade 4 mars 2013

What other segment sizes did you test? You need a lot of samples (I would say at least 50 for this problem) to analyse the trend---it is not as unambigious as one might think!

Although it is interesting to study the trend and analyse how the segment size affects the resutls, please notice that the question is about the importance of the segment size and whether it changes the conclusion on the profitability of the wind farm investment.

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kommenterade 5 mars 2013

I used segment sizes 100, 75, 50, 25 and 1. So maybe I should test for segment sizes below 10ish to get above 50 samples? The problem is that I do not see any clear trend between segment size reduction and ETOC for example. What I was hoping to see was that ETOC or LOLP would decrease or increase as I was reducing my segment size. However I can not draw such a conclusion because it seems to be nonlinear. Intuitively I would think that a segment size reduction increases the number of samples and thus makes the expected result variables more accurate. Even though this might not affect the question stated in the problem, I find it hard to understand why we get such "random" variations in the expected result variables when decreasing the segment size.

Anmäl missbruk
Lärare kommenterade 5 mars 2013

The segment size reflects how well the approximate duration curves corresponds to the real curve. What you describe as "random" variations is more of a threshold effect, when certain points of the approximate curve moves due to changes in the segment borders.

If you want to study the trend, it is better to test evenly distributed segment sizes up to 100 MW (for example 100, 95, 90, ... 5 MW or---if you have patience enough---100, 99.5, 99, ... 0.5 MW).

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kommenterade 25 januari 2014

Do we need to make presentations for bonus problems?

Anmäl missbruk
Lärare kommenterade 27 januari 2014

The details are explained in the course syllabus

Anmäl missbruk
kommenterade 12 februari 2014

Hej!

Jag har en frågan gällande hemuppgifter del 3 och del 4 och vilka uppgifter som är seminarieuppgifter och vilka som är bonusuppgifter.

För del 3: stämmer det att seminarieuppgifterna är uppgift 12-14 samt uppgift 17 och att bonusuppgifterna är uppgift 15-16?

För del 4: är seminarieuppgifterna till denna del uppgift 18-20, 22-23 samt uppgift 26 och att bonusuppgifterna är uppgift 21 och uppgift 24-25?

Tacksam för svar!

Anmäl missbruk
Lärare kommenterade 13 februari 2014

GAMS LICENCE PROBLEMS

There has been a problem with our GAMS licence. A new licence has now been installed in the Student room, Teknikringen 33. This licence may not be available if the computer has not been restarted. Hence, if you receive error messages concerning the GAMS licence, try restarting the computer. If the problem persists then please report which computer you have been using to me and try to log in on another computer.

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