Topic: SM: P VM A-2.4 Select Power Source (21) Part 2: Solar Panels

[snrdg051306]

Please note that this topic was originally posted on 4/11/2011


Q1: What is the base TL for solar panels in SM: P

So far I haven't found any mention of a TL for solar panels in any of the material I have. I am guessing that TL 14 is a possibility after looking at SM: P TL VM Part II Technological Development pp. 6 - 14.

Q2: What other systems besides computers and life support would receive power from solar panels?

Recap: MarkC and Defendi recommended that any system with a negligible power requirement draws power from solar panels.

Systems with negligible power requirement
1. Microfreq Comm Rig - p. 111 - Yes
2. Basic Sensor Suite - p. 112 - Yes, unless Advanced Suite selected
3. Life Support - p. 118 - Yes already designated
4. Recreational Facilities - p. 118 - Only if used for food storage/preparation.
5. Sick Bay - p. 119 - Yes
6. Labs - p. 119 - Depends on if lab can support repairs and there aren't any workshops
7. Workshops - p. 119 - Yes
8. Security Stations - p. 119 - At least one if installed
9. Fighter Bays - p. 119 - Only if being used for housing people or evacuating ship.
10. Vehicle Bays - p. 119 - same comment as Item 9.

Additional recommendations:

1. I would include all of the communication rigs installed.
2. Defensive Screens powered to at least 1 if radiation shielding is not installed. Radiation Shielding does not have a power requirement per VM p. 120.


Q3: How do you calculate the power output from solar panels?

I've been working on this but so far my only suggestion was to into the surface area in square meters x 0.01. After some more thought I realize that the selected surface area could be more than available on the ship and/or not match the mass calculated on p. 116.

My research has shown that solar panels today have an average conversation factor of solar to electrical power of about 8 to 25%. I haven't found anything about the conversion factor for the International Space Station. MegaTraveller and Traveller: New Era each have a method of figuring out solar panel/array performance. Unfortunately, I'm not sure how the Traveller TL or real world TL corresponds to SM: P TL.

[markc]

 Tom R;
 I would not include defensive screens in the solar power list as they take too much power IMHO. You should install some level of rad shielding as a standard of construction if things can be damaged by radiation.
 IMHO the power level would increase with TL as other power plants do. So at low TL's they would be 8% and at high TL's they might be as high as 40%. But I am just guessing and have not done any research at all on the subject or some of the "magical" materials that appear in the future. 


 Again I do not know how to determine the surface area in SM:P without some shape and subtraction of said area by equipment that takes up surface area. You could wave you hand and say ok the surface area is equal to the mass of the craft or a % of the mass of the craft as a general rule.


 I also have not had time to build anything as my quick pick up game was nixed do to bad back problems achieved by trying to do to much when my friend decided to drop by for a few days.


MDC   

[snrdg051306]

Morning MarkC,

Thanks for the feedback and I hope your back is feeling better. Looks like we both have had some fun the last couple of weeks. My tooth is gone, I feel much better, and I've started working on the spreadsheet again.

I have done a quick look the SM: P TL VM 6.3 concerning radiation shielding (RS) and defensive screens (DS) here is what I found:

Courier Shuttle p. 27: neither RS or DS installed
Death Howl II p. 28: DS installed
Goliath p. 28: RS installed
Kizzari Military Packet p. 30: DS installed
Hierarch FTL Shuttle p. 30: neither RS or DS installed
Life pod p. 31: neither RS or DS installed
Maintenance Pod p. 31: neither RS or DS installed
Small Orbital Shuttle p. 31: neither RS or DS installed
Large Orbital Shuttle p. 32: neither RS or DS installed
S-5B Sparrow p. 33: DS installed
S-8B Hawk p. 33: DS installed
S-9C Blood Hawk p. 34: DS installed
S-12B Hammer p. 34: DS installed
S-17B Thunderstroke p. 35: DS installed
Slashing Blow III p. 35: DS installed
Warthog Medium freighter p. 37: neither DS or RS installed
Wolverine p. 37: DS installed
Zephyr Light freighter p. 37: RS installed
Izzari Police gunboat p. 38: DS installed
Kalzari System Patrol Boat p. 38: DS installed
Raptor Response gunboat p. 39: DS installed
Fat Brat Border Patrol Boat p. 39: DS installed
Design Example p. 113: DS installed

Looking over the list I'd say that defensive screens have largely taken over for radiation shielding and would be on the list of systems that get some of the solar panel's power output. I have to agree that the defensive screens wouldn't be powered to the full rating unless the vehicle is in a high radiation area.

SM: P solar panels are, in my understanding, intended as an emergency power source which has a list of critical systems that get power. Of course the list gets juggled depending on the situation as to which systems gets powered.

If my vessel has defensive screen and radiation shielding I'd shutdown the defensive screen. If I've only got the defensive screen I'll use the lowest power draw setting to get protection. If I don't have either I'm really hoping for a place I can hide in like Ben Bova suggested in Book 1 "The Precipice" of the Asteroid Wars series. The crew of the first fusion powered spaceship had to shutdown their radiation shielding, which is some sort of super conductor system, due to sabotage and of course a really bad solar storm kicks up. The crew uses chondritic asteroid as a storm shelter.

I had a similar thought about using a scale of increasing the solar panel power output with the tech levels. Unfortunately, without a handle on which TL to start solar panels at the idea is on the shelf waiting for clarification from on high.

MegaTraveller has a formula for calculating the maximum square meters of surface area available for solar panels/cells. The formula takes the square root of the vehicles volume. In the TL VM A-2.4 design example the TMAC has a volume of 300 kiloliters which, using MegaTraveller's formula, gives us a maximum surface area of 300^(1/2) = 17.3205 square meters for solar panels. The next step would then multiply the srface area by the 8 to 40% or whatever the effeciency rating that a solar panel has covnerting solar radiation to usable power.

I've been wondering if you had a chance to try the spreadsheet yet. I've completed Determine Minimum crew (22), after having to rebuild Select Power Source (21). Of course I've got some more comments/questions for both Steps 21 and 22.

Again thanks for the assistance you've provided.

[snrdg051306]

I have finally found some information on the power output of the International Space Station's 4 large Photovoltaic (PV) arrays (solar panels) which is between 20.9 to 32.8 kW per array. Each array has a surface area of 375 m^2.

What is the unit of measure for power output of a reactor, solar panel and/or generator?

[CharleyRhines]

I have finally found some information on the power output of the International Space Station's 4 large Photovoltaic (PV) arrays (solar panels) which is between 20.9 to 32.8 kW per array. Each array has a surface area of 375 m^2.

What is the unit of measure for power output of a reactor, solar panel and/or generator?

Thanks for sharing those figures.. I still believe PV system in expensive and ineffective way of generating power.

[arakish]

Sorry for posting so late...

Thanks for sharing those figures.. I still believe PV system in expensive and ineffective way of generating power.

But if you ain't got nothing else for power, PV systems can be life savers.

Q1: What is the base TL for solar panels in SM: P

So far I haven't found any mention of a TL for solar panels in any of the material I have. I am guessing that TL 14 is a possibility after looking at SM: P TL VM Part II Technological Development pp. 6 - 14.

Actually, we have known about PV systems since TL 13.  It was just that our technology at that level could not use them very effectively.

Q3: How do you calculate the power output from solar panels?

I've been working on this but so far my only suggestion was to into the surface area in square meters x 0.01. After some more thought I realize that the selected surface area could be more than available on the ship and/or not match the mass calculated on p. 116.

My research has shown that solar panels today have an average conversation factor of solar to electrical power of about 8 to 25%. I haven't found anything about the conversion factor for the International Space Station. MegaTraveller and Traveller: New Era each have a method of figuring out solar panel/array performance. Unfortunately, I'm not sure how the Traveller TL or real world TL corresponds to SM: P TL.

Here is what we have used:
TL        Energy Factor
13        1
14        2.5
15        5
16        10
17        25
18        50
19        100
20        250
21        500
22        1000
23        2500
24        5000
25+      continue progression

The energy factor is the amount of kW of power per square meter of the PV panels.  Using the numbers provided by snrdg051306, the ISS panels produce about 14kW per square meter placing the TL between 16 and 17, which is about right for today.

Anyone got a better way?

rmfr

[CharleyRhines]

I have finally found some information on the power output of the International Space Station's 4 large Photovoltaic (PV) arrays (solar panel) which is between 20.9 to 32.8 kW per array. Each array has a surface area of 375 m^2.

What is the unit of measure for power output of a reactor, solar panel and/or generator?

Thanks for sharing those figures.. I still believe PV system in expensive and ineffective way of generating power.

[arakish]

Here is what we have used:
TL        Energy Factor
13        1
14        2.5
15        5
16        10
17        25
18        50
19        100
20        250
21        500
22        1000
23        2500
24        5000
25+      continue progression

The energy factor is the amount of kW of power per square meter of the PV panels.  Using the numbers provided by snrdg051306, the ISS panels produce about 14kW per square meter placing the TL between 16 and 17, which is about right for today.

Anyone got a better way?

rmfr

Wrote the above from memory, when I looked it up and I forgot one thing about PV panels.  We also had an equation that compensated for how close you were to a star and its luminosity factor in terms of Sol.

P = s × F × L; where P = power generated, s = size of panel in square meters, F = factor as above, and L = luminosity factor in terms of Sol.

Even if the star is equal to Sol (our star), if you were in orbit about Jupiter, then L would equal 0.037 since Jupiter receives only about 51 W/m^2 compared to Earth's at about 1367 W/m^2.  Thus, if you had TL20 PV panels and in orbit about Jupiter, they would produce 9.25 kW power per square meter (1 × 250 × 0.037).

If you were at the equivalent distance of Earth from an F2-V star, then those same PV panels would produce 3250 kW per square meter since the F2-V star would have a luminosity factor about 13× Sol (1 × 250 × 13).

Here is a table for each planet in our system showing the value for "L".  Remember, the "L" factor is using the mean solar irradiance.

Object		"L" factor
Mercury		7.577907827
Venus		1.91038771
Earth		1
Mars		0.441477688
Jupiter		0.037198244
Saturn		0.01100951
Uranus		0.00271763
Neptune		0.001100951
Pluto		0.000775421

Now you can kind of see why the Voyager probes needed those nuclear reacters for power out there at Saturn, Uranus, and Neptune, and beyond.

To find the flux (energy received) received from a star: F = L ÷ (4 × PI × d^2); where F = flux received, L = luminosity in terms of Sol, PI is the constant, d = distance from emitter in AUs.

rmfr