HG vs TCS Fuel Purification Plants

[Gruffty]

This is a spin off from my thread in the Software Solutions board about fuel purification plants.

According to HG (2ed), at TL-15, 1,000 dTons of fuel requires one, 15 dTon, Cr 130,000 fuel purification plant. Logically then, 2,000 dTons of fuel would need double the quoted figures, 3,000 dTons of fuel three times, and so on.

Correct? Oui? Non? n'est pas? Right.

According to p. 14/15 of Trillion Credit Squadron:

The Percentage-Based Fuel Purification Plant Table (on p. 15 of TCS) shows those plants as a percentage of the fuel tankage of a ship, and includes the minimum tonnage required and the cost per ton of percentage-based fuel purification plant installed. The table simply restates the Fuel Purification Plant Table (i.e. the one in HG) in different terms.

So, theoretically, we should be able to reproduce any HG-built fuel purification plant using the TCS FPP rules. Still with me? Good......

 

[Gruffty]

So let's do that then. To keep the maths simple we'll bypass some of the design process and jump straight to looking at fuel requirements. Our theoretical ship is constructed at TL-15, requires exactly 1,000 dTons of fuel to power its Jump drive and Power Plant and has fuel scoops included in the hull design. The naval architect wants this ship to be able to carry out wilderness refuelling and thus the ship requires a Fuel Purification Plant (FPP).

So, according to HG our theoretical ship with its 1,000 dTons of fuel requires one 15 dTon, Cr 130,000 FPP. Correct so far? Yup.

Now let's apply the TCS FPP construction process to our theoretical ship:

1,000 dTons of fuel / 100 (to get 1%) = 10;
10 * 0.15% (% of fuel at TL-15) = 1.5 dTons for the FPP (ignore the TCS minimum dTons issue for the moment);
1.5 dTons * Cr 10,000 (cost at TL-15 per ton of FPP) = Cr 15,000.

The HG FPP is not the same as the TCS FPP for the same amount of fuel, at the same TL.

So either:

1. The HG FPP table is wrong;
2. The TCS FPP table is wrong;
3. Both the FPP tables are wrong;
4. I have gone wrong with the maths somewhere above.

Your thoughts and ideas on this, gentle sophonts, would be most welcome.

 

[Plankowner]

I would say TCS is wrong.

It should be 1.5% not 0.15% in the TCS formula.

1.5dtons seems VERY small for a refinery for 1000 tons of fuel.

ANOTHER QUESTION:

I looked through HG and couldn't find out HOW LONG it takes the Purification plant to purify that 1000 tons of fuel. 1 turn, 1 day, 1 week? I couldn't find it anywhere in LBB 5.

 

[Gruffty]

I would say TCS is wrong. It should be 1.5% not 0.15% in the TCS formula. 1.5dtons seems VERY small for a refinery for 1000 tons of fuel.

I agree. If we move the decimal point on all of the TCS values for % of fuel, the results are *exactly* the same as HG; only the cost differs.

ANOTHER QUESTION:

I looked through HG and couldn't find out HOW LONG it takes the Purification plant to purify that 1000 tons of fuel. 1 turn, 1 day, 1 week? I couldn't find it anywhere in LBB 5.

Ditto. AFAIK, the actual time to purify the unrefined fuel is only clearly laid out in MT:RM, but nowhere within LBB 5. MT says that a FPP of the correct size can purify all the fuel in the tanks in 6 hours; it goes on to say that a FPP of half the required size would take 12 hours.

So for our theoretical ship that would be 1,000 dTons of fuel purified in 6 hours by a 15 dTon, Cr 130,000 FPP.

As to the costs of FPPs, I noticed that T20 uses the same cost values as TCS, not HG. All 3 system (HG, TCS, T20) use the minimum dTons per FPP rule, and all 3 systems use exactly the same values by TL. I haven't yet looked at T4, TNE or G:T but will do, cos I'm like a dog with a bone with this sort of thing I'll ask Hunter where he got the cost/minimum dTons for T20 from.

 

[Gruffty]

Interestingly, p. 267 of T20 says that it takes 20-TL of FPP hours to refine 200 dTons of fuel. It goes on to say that multiple FPPs can be used to increase the amount of fuel processed at any given time.

So, for a TL-15 FPP in T20, it takes 5 hours to refine 200 dTons of fuel.

For 1,000 dTons of fuel, we could install five, 3 dTon FPPs (= 15 dTons total, the same as HG) with each processing 200 dTons (5 * 200 = 1,000) of fuel every 5 hours.

I've also checked this up in the G:T book.

Each Fuel Processor module can process 8 "jump fuel modules" of unrefined fuel per hour. The number of "jump fuel modules" a ship requires is the same as 0.1 * hull dTons * Jump drive number (as per CT:HG). G:T uses the term "spaces" to indicate a volume of hull dTons; thus 1 dTon in CT = 1 "space" in G:T.

So, for our theoretical ship, in G:T the 1,000 dTons of fuel becomes 1,000 "jump fuel modules"; 1,000 / 8 = 125 Fuel Processors, @ Cr 850,000 each = MCr 106.25 - all unrefined fuel is processed in an hour!

 

[Plankowner]

{snip}

So, for our theoretical ship, in G:T the 1,000 dTons of fuel becomes 1,000 "jump fuel modules"; 1,000 / 8 = 125 Fuel Processors, @ Cr 850,000 each = MCr 106.25 - all unrefined fuel is processed in an hour!

THAT seems a bit high. 106Mcr for a fuel processor? I like the T20 values a LOT more.

Regarding 5 vs 6 hours. I don't consider that 20% difference too bad at all. Close enough for MTU!

 

[Gruffty]

I've just had another look at the FPP tables in HG and TCS, specifically in relation to cost/dTon.

The HG FPP table cost columns ends with Cr 150,000 for a 15 dTon FPP. I thought this was wrong, as the previous entry for TL-13 is 150,000, TL-14 is 140,000 then TL-15 is 150,000. Wrongly I dropped this to 130,000 on the basis of cost reduction by TL improvement.

However, take a look at the TCS table. It shows TL-15 FPPs costing Cr 10,000 per dTon. If we accept that the % column is wrong (and thus we move the decimal point one place to the right, making TL-15 FPPs require 1.5%), 1,000 dTons of fuel will reuqire a 15 dTon FPP at a cost of Cr 150,000 - exactly the same as the TL-15 FPP in HG.

I haven't looked at the costs for the lower TL FPPs yet, but will do. As an aside, T20s FPPs are priced nearly the same as TCS (there is a small amount of rounding involved, but they're only a few Cr apart).

COMBINED HG & TCS FUEL PURIFICATION PLANT TABLE (CORRECTED)

     Min.
TL   Size  Tons  Cost      %    per Ton
---------------------------------------
 8   10    50    200,000   5.0    4,000
 9    9    45    190,000   4.5    4,222
10    8    40    180,000   4.0    4,500
11    7    35    170,000   3.5    4,857
12    6    30    160,000   3.0    5,333
13    5    25    150,000   2.5    6,000
14    4    20    140,000   2.0    7,000
15    3    15    150,000   1.5   10,000

I think that makes sense, now.

 

[Gruffty]

Calculating the cost per dTon (% based from TCS) against the "bulk" cost (from HG), the prices are very close:

   Min. |              |     Cost/  | TCS     |
TL Size | Tons HG Cost | %   Ton    | Cost    |
--------|--------------|------------|---------|
 8 10   | 50   200,000 | 5.0  4,000 | 200,000 |
 9  9   | 45   190,000 | 4.5  4,222 | 189,990 |
10  8   | 40   180,000 | 4.0  4,500 | 180,000 |
11  7   | 35   170,000 | 3.5  4,857 | 169,995 |
12  6   | 30   160,000 | 3.0  5,333 | 159,990 |
13  5   | 25   150,000 | 2.5  6,000 | 150,000 |
14  4   | 20   140,000 | 2.0  7,000 | 140,000 |
15  3   | 15   150,000 | 1.5 10,000 | 150,000 |