Where are the mine life values used in the DCF?
What is "Tons Processed [Tons Proce]"?
How do we export the discount rate used in the DCF?
What consitutes not enough coal to mine?
Can CoalVal calculate different results with the same input?
Question: Can CoalVal calculate different results with the same input?
Answer: The question has been raised concerning if CoalVal could produce different results with the same input. The answer is it depends on the version of CoalVal that you are using. If you are using a version earlier than 1.2.8 then the answer is that for Longwall you can get the wrong answer. But if you calculate the DCF report twice on the same areas then the answer will be correct. So it appears that you can get different results with the same input for versions earlier than 1.2.8, but if re-calculated you will get the correct results.
I have tested versions 1.2.12 and 1.1.10 of CoalVal in comparison to "longwall_v2.xls" DCF calculations for ROM coal, parting, and dilution. The results are as follows for CoalVal version 1.2.12:
Production ----CoalVal
1.2.12------- Excel Workbook
Coal --------------378,877 ------------------------378,877
Parting ----------424,087 ------------------------424,087
Dilution ----------146,237 -----------------------146,237
Development -----CoalVal 1.2.12-------- Excel Workbook
Coal --------------------1,767,958 ----------------1,767,958
Parting -------------------198,148 ------------------198,148
Dilution -------------------136,654 ------------------136,654
I get the same results with version 1.1.10 if I recalculate DCF.
The problem with any CoalVal version prior to 1.2.8 is the floating point error that we were all were getting. If you read the fixes section on the web site for version 1.2.8 you will see that the problem was a un-initialized variable. What this means is that the variable has a memory location in the memory of the computer it is running on. Since the variable has not been initialized, the value for the variable is what ever happens to be in that memory location. When I ran a new area with a Longwall mine model, I found that version 1.1.10 would not calculate the development properly for DCF until I re-calculated it again. For version 1.2.12 I found no such problem.
Question: What constitutes not enough coal to mine in a fractional LPU?
Answer: We know the yearly tons to be mined are based on the mine model chosen for an area. We also the mine life in years and from this we get the total tons for 1 LPU by "yearly tons" * "Mine Life". To get the tons for the fractional LPU the following formula is used: "TonsForFracOfLMU := TonsFor1LMU * Frac(NumLMU). We assume that you need al least enough coal for one year of mining. If the tons for a fractional LPU is greater than the yearly tons, DCF yealy report is calculated. If not, then there is not enough coal to mine, so no DCF yearly report is not calculated.
Question:
Is LOMAcres and other LOM fields calculated using the mine model mine
life
or the calculated mine life?
Answer: A Mine Model does not have a "Mine Life", only resources areas have a "Mine Life". The "Mine Life" is entered on the Resource Area page of the Projects window. The "Mine Life" may be different from what the user entered if a DCF resource area has been calculated using fractional LPU's. In this case the "Mine Life" used is the CoalVal calculated fractional "Mine Life".
Question: "Minimum Mine Life" is not necessarily the minelife used to calculate the threshold price since the spreadsheet shows only 10s and 5s. Where are the mine life values used in the DCF?
Answer: Fraction
Mine Life and Fractional LPU's has been added to the data export as of
version 1.2.9.
Question: What is "Tons Processed [Tons Proce]"?
Answer: It is an old field that is no longer used. It has been removed from the data export as of Version 1.2.9.
Question: (On a data Export Excel Workbook) -- The IRR is listed as zero in the spreadsheet, although the hurdle rate is10% as Lee entered it on Projects=>"Seams, Areas, and Discounted Cash Flows"=> Seams page. How do we export the discount rate used in the DCF?
Answer: First of all we are not using Internal Rate of Return, we are using Net Present Value in our DCF calculations. The field IRR was used when CoalVal calculated DCF by either IRR or the NPV methods.
Version 1.2.9 will
export the "Hurdle Rate" from the Seam table.
top
Question:
How do I know the answers to the questions shown on the DCF reports page
for each resource area (By looking at the data export workbook)? -
Resource area has been calculated?
Area is at least one LPU?
Calculated Report uses fractional LPU?
Answer: Download
version 1.2.9. This version allows for the exporting of the answers to
these 3 questions.
