Power plant question

[Carlobrand]

I have a choice at TL9. I can use a standard CT 250 Mw fusion power plant at a cost of MCr12, fuel cost is cheap; MT's power plant is cheaper for some reason, but I'm not considering that at the moment. Or, and here's where it gets confusing:

• MegaTraveller proposes a TL8 252 Mw MCr1.05 MHD power plant consuming 3.675 Kl/h at a cost of Cr918.75/h;
• Striker proposes a TL8 250 Mw MCr 2.78 MHD power plant consuming 75 Kl/h at a cost of Cr18,750/h.

Which of these MHD plants is more realistic? I know essentially zip about power plant engineering other than what I can look up on-line, and I'm not sure I know enough to even formulate a decent search. Near as I can figure, a power plant that size could power a city of a couple hundred thousand.

 

[Condottiere]

I don't know about realistic.

I would pick the one that most fit for purpose, or, alternatively, cheapest to use.

 

[AnotherDilbert]

MT:
Target: 250 MW.
250 MW / 0.8 MW/m³ / 1.5 scale ≈ 208.33 m³ ≈ 210 m³ plant.
fuel consumption is 210 × 0.035 m³/h = 7.35 m³/h.

Striker:
250 / 0.6 / 1.5 ≈ 277.78 ≈ 280 m³ plant.
Fuel consumption: 280 × 0.6 × 1.5 × 0.3 m³/h = 75.6 m³/h.


MT is lala-land...
250 MW is something like 1000 ~350 hp car engines going on full throttle. If you believe a car engine can run for an hour on full throttle on 7 l ≈ 2 gallons (colonial), I have a bridge to sell you...


Petrol has an energy content of about 13 kWh/kg.
250 MW for an hour is 250 000 kWh. The efficiency of a turbine is 50% (guessing), so we need 500 000 kWh worth of fuel.
500 000 kWh / 13 kWh/kg ≈ 38 500 kg = 38.5 tonnes.
With a weight of about 0.7 kg/l or tonnes/m³, that would be 55 m³/h.
Conclusion: Striker is much closer to reality...

 

[atpollard]

MT is lala-land...

Conclusion: Striker is much closer to reality...

While this is probably 100% correct (I did not confirm his arithmetic, but it looks right at first glance), it is worth noting that FUSION PP* are also in "lala land" so that MT may have just balanced the "lala land" to be more equal. That makes the decision a matter of DESIGN INTENT (greater realism vs greater game mechanics balance) ... which is for each individual IMTU to decide what is THEIR priority.

At least @AnotherDilbert had given you the tools to make an informed decision.

*[250 MW is a LOT of power ... like a LOT of LOT ... as noted: "1000 x 350 HP engines" scale a LOT ... that is some "vehicle"!]

 

[kilemall]

You can always put your thumb on the scale and increase things like gravitics power consumption.

 

[whartung]

MT and CT are not compatible rulesets. You can't mix and match. It's apples and oranges. If you're going that route, just make stuff up until you're happy. What difference does it make?

 

[kilemall]

MT and CT are not compatible rulesets. You can't mix and match. It's apples and oranges. If you're going that route, just make stuff up until you're happy. What difference does it make?

CT Striker as I understand it was the start of the quantification kick that culminated in MT and was revisited in TNE, so maybe inspired is the right word.

CT Striker is so fussy that while I use it for resolution I don’t build vehicles with it. I use the MgT2 Vehicle Handbook, eyeball the armor costs/value, slap the Striker weapons on and go.

Among other things allows quick custom items to be built- go to the dealership, test drive a base chassis, lay down the credits, 48 hours later the makers have built the new vehicle.

Do the same thing with the guns, using either the MgT2 merc gun builder, T5, or the armory house rules. I can value em and use the chrome language to spec what they got. Always Christmas going to the Gun Maker store.

 

[Tobias]

250 Mw is ~ 10 times the stated maximum output of the popular LM2500 turbine, which has a fuel consumption of 227g/kwh, so 5.675 tons per hour. STRIKER values are much closer to our reality than MT's.

 

[AnotherDilbert]

MT and CT are not compatible rulesets. You can't mix and match.

In this case they are near identical:


It is only the fuel consumption that differs significantly.

CT Striker and LBB5 is the basis for the MT craft design system.

 

[Tobias]

MT and CT are not compatible rulesets. You can't mix and match. It's apples and oranges. If you're going that route, just make stuff up until you're happy. What difference does it make?

Many (almost all for the standard tech levels) things in the MT design system are taken directly from CT.

Speaking of which:

I have a choice at TL9. I can use a standard CT 250 Mw fusion power plant at a cost of MCr12, fuel cost is cheap; MT's power plant is cheaper for some reason, but I'm not considering that at the moment. Or, and here's where it gets confusing:

• MegaTraveller proposes a TL8 252 Mw MCr1.05 MHD power plant consuming 3.675 Kl/h at a cost of Cr918.75/h;

This uses the errata'd values. The orginal values in the Referee's Manual are in fact exactly the same as in STRIKER - with one exception: Scale efficiency does not increase fuel consumption in MT (because fuel consumption is calculated as a multiple of power plant size, not output).

ISTR (Yeah, just checked it) the errata massively increasing the fuel efficiency of non-fusion PPs go back to the original run of MT (they were published in The Traveller's Digest 13 by DGP) rather than having been added later by DonM.
I assume DGP errata'd the values based on the vehicles they wanted to design, not on realistic considerations of fuel efficiency. DGP, and I am just going to say it, were not as interested or knowledgable in engineering and military topics as the GDW folks had been - they were more about exploratory science and role-playing rules.

 

[Carlobrand]

I was suspicious of the MT value given what they did with fuel cells. This is for a colony, not a vehicle, so I don't have to worry about vehicle design (although there's no generator rules, so it's a bit of a stretch). Trying to see if it was more efficient for the colony to install a non fusion power plant and pay the fuel cost versus the cost of a fusion plant.

 

[kilemall]

I was suspicious of the MT value given what they did with fuel cells. This is for a colony, not a vehicle, so I don't have to worry about vehicle design (although there's no generator rules, so it's a bit of a stretch). Trying to see if it was more efficient for the colony to install a non fusion power plant and pay the fuel cost versus the cost of a fusion plant.

I suppose that depends on the colony’s fuel supply.

 

[Carlobrand]

I suppose that depends on the colony’s fuel supply.

Probably. At a thousand credits per 13.5 kiloliters, importing hydrocarbon fuels gets expensive, not to mention we'd either need a regular trader or a large storage facility to store enough between visits. Recovering and refining local fuel sources requires there to be local fuel sources plus some infrastructure to do it, so that option might not be open to some colonies. Biodiesel? Alcohol?

 

[Marcatlas]

I have a choice at TL9. I can use a standard CT 250 Mw fusion power plant at a cost of MCr12, fuel cost is cheap; MT's power plant is cheaper for some reason, but I'm not considering that at the moment. Or, and here's where it gets confusing:

• MegaTraveller proposes a TL8 252 Mw MCr1.05 MHD power plant consuming 3.675 Kl/h at a cost of Cr918.75/h;
• Striker proposes a TL8 250 Mw MCr 2.78 MHD power plant consuming 75 Kl/h at a cost of Cr18,750/h.

Which of these MHD plants is more realistic?

Neither. The fuel consumption is thousands of times higher than it should be. Use Fusion PPs from Cepheus deluxe and match the size of them using what it takes for an MT power plant to power Jn for a certain hull sizehull size.

 

[Tobias]

For a colony, it may be worthwhile to look into renewables. Of course, those aren't really covered by either CT or MT.

 

[Marcatlas]

For a colony, it may be worthwhile to look into renewables. Of course, those aren't really covered by either CT or MT.

For Base load generation? Not viable vs even a portable fission generator.. Unless they happen to have a great geothermal or an easily, large damable source of water

 

[Condottiere]

Depends on how large and extensive the colony is.

If feasible, distributed power grid, if possible, technological level eight mini fusion reactors.

 

[Carlobrand]

Neither. The fuel consumption is thousands of times higher than it should be. Use Fusion PPs from Cepheus deluxe and match the size of them using what it takes for an MT power plant to power Jn for a certain hull sizehull size.

I have no experience with Cepheus. Is that books? Software? How do I access it?

For a colony, it may be worthwhile to look into renewables. Of course, those aren't really covered by either CT or MT.

That's a good idea. MT has solar panel rules, but I think they're drawing extra power from the ether. The only thing I have with renewables is someone parking in orbit and saying, "That's a real nice wind farm you've got there. It'd be a shame if something happened to it."

Of course, that's true of pretty much everything. There'd need to be some sort of minimal planetary defense set up to discourage that kind of thing. Larger communities can afford planetary defenses substantial enough to at least stop casual threats, so that's a good solution for them assuming the environment supports it. For smaller communities, best they can probably do is to put their power plant in a bunker with a cheap point defense system to knock down missiles.

 

[Marcatlas]

I have no experience with Cepheus. Is that books? Software? How do I access it?

Cepheus Deluxe is a version of "Traveller" based on the Mongoose Traveller SRD. There is a forum on this board dedicated to it. DriveThru sells it.

 

[Tobias]

For Base load generation? Not viable vs even a portable fission generator.. Unless they happen to have a great geothermal or an easily, large damable source of water

Of course, it really depends on the environmental conditions. Different worlds would offer different possibilities: A tidally locked world could use solar panels on the bright side, and transfer energy to the habitable twilight zone; or make use of a large-scale heat differential machine. On the other hand, a world with massive tidal forces could utilize those.