baithammer
Mongoose
Ugh forgot to put "as if thrust 1".
High Guard 2e - Solar Panels
- Thread starter Pyromancer
- Start date
AnotherDilbert
Emperor Mongoose
Not quite, the solar panel are based on an imaginary PP-1, but still does not allow manoeuvring.DickTurpin said:
That kind of performance is theoretically possible, provided the solar "panels" are an extremely thin film.
http://forum.mongoosepublishing.com/viewtopic.php?f=89&t=119491&p=908896&hilit=solar#p908881
PsiTraveller
Cosmic Mongoose
Well the 1 ton of solar panels is the volume of very thin panels all folded up. Fold things out to catch the sun and assume the panels are 1cm thick. 1m3 of storage space is now 100 m2 of unfolded panels.
1 dTon is 1400 m2 of unfolded panels.
Or make the panels thinner and have a larger surface area. The film may be hectares in size.
Maybe they are inflatable balloins of mylar that inflate to massive size and concentrate the sunlight onto a central point. This is what creates the power. They could be hundreds of meters in diameter. These solar power bubbles prevent the movement of the ship.
1 dTon is 1400 m2 of unfolded panels.
Or make the panels thinner and have a larger surface area. The film may be hectares in size.
Maybe they are inflatable balloins of mylar that inflate to massive size and concentrate the sunlight onto a central point. This is what creates the power. They could be hundreds of meters in diameter. These solar power bubbles prevent the movement of the ship.
DickTurpin
Banded Mongoose
AnotherDilbert said:
Good catch. Since the solar panels are 1/10th the size of a fusion plant that would provide 30 power yet they only provide 20 power, the actual power/ton ration is actually 20/3rds (say 7x) in favor of the solar panels. It still seems excessive.
AnotherDilbert said:
We were talking about the power generating capacity of solar sails, not the thrust provided by solar sails. There is no reason the two could not be used together such as a solar sail made of or lined with a power generating film but that is another discussion.
baithammer
Mongoose
Solar Sails don't generate power, solar panels do.
AnotherDilbert
Emperor Mongoose
Solar cells can be a thin layer on a thin film substrate, so that a solar "panel" would look like a solar sail. The solar sail acceleration would be negligible.DickTurpin said:
Even a small ship would need a square kilometre or so of panel, so a thick, solid panel is quite impractical.
AnotherDilbert said:
Slightly different topic - there’s been proposals to use high-albedo coatings applied to asteroids to force them (very gradually I assume) into a different and presumably less dangerous orbit. Given the low thrust calculated for solar sails, is that idea even remotely possible?
AnotherDilbert
Emperor Mongoose
I would guess that it is not very practical. A painted asteroid would have much lower acceleration than a spacecraft with a solar sail.Linwood said:
At less than a millionth of a g it would gain 0.1 km/s or so per year of acceleration (in Earth orbit, much less in the belt). It would take decades to change the asteroids orbit even a little.
Sigtrygg
Emperor Mongoose
Oh its practical - it could be done with current technology in very little turnaround time. The draw back is it takes years to perturb the orbit of the asteroid.
So it is a serious proposition for an Earth crossing asteroid that 'may' impact in 30+ years time. It is of no use whatsoever against something that is going to hit in only a few months or years time.
So it is a serious proposition for an Earth crossing asteroid that 'may' impact in 30+ years time. It is of no use whatsoever against something that is going to hit in only a few months or years time.
Reynard
Emperor Mongoose
My interpretation concerning Traveller solar panels. First, a vessel's power plant also includes a lot of empty space. The displacement is not a solid block. A solar panel array is tightly and efficiently packed until deployed. It includes bracing and armatures to extend a huge yet thin surface area with energy catching cells that are probably more advanced than we have today in order to explain the amount of power they absorb. The size explains one reason they can't be deployed when jumping, it most likely extends beyond the jump bubble. Any velocity above 1g will tear the array apart.
The array is used mostly to supplement a power plant to reduce fuel use. A vessel with no power plant cannot sustain functions much beyond minimal basic power and maneuvering without sacrificing other priority systems (See Running Out of Power, CR. pg. 144). Vessels without power plants are more often satellites and stations equipped with station keeping 0g thrusters at best. The Thrust 1 motive system would allow the craft the extra ability to reposition itself as well as hold a stable position and only for very short distances rather than interplanetary trips. It's minimally maneuvering between 0g and 1g thrust.
By not manuevering (M drive is turned off), you can run a station without fuel. There's enough power for basic needs plus the power points for operating the M-drive can be allocated to other power point using systems. Position corrections would mean shutting down systems (dimming the lights) to operate the M-drive for brief periods. If there is power left over with M-drive shut down, those power points could be added to High Efficiency Batteries which can hold enough charges to fire energy weapons as well as powering the turret a finite number of rounds. Missile and sandcasters won't need power but the turrets will.
The array is used mostly to supplement a power plant to reduce fuel use. A vessel with no power plant cannot sustain functions much beyond minimal basic power and maneuvering without sacrificing other priority systems (See Running Out of Power, CR. pg. 144). Vessels without power plants are more often satellites and stations equipped with station keeping 0g thrusters at best. The Thrust 1 motive system would allow the craft the extra ability to reposition itself as well as hold a stable position and only for very short distances rather than interplanetary trips. It's minimally maneuvering between 0g and 1g thrust.
By not manuevering (M drive is turned off), you can run a station without fuel. There's enough power for basic needs plus the power points for operating the M-drive can be allocated to other power point using systems. Position corrections would mean shutting down systems (dimming the lights) to operate the M-drive for brief periods. If there is power left over with M-drive shut down, those power points could be added to High Efficiency Batteries which can hold enough charges to fire energy weapons as well as powering the turret a finite number of rounds. Missile and sandcasters won't need power but the turrets will.
PsiTraveller
Cosmic Mongoose
I want clearer rules for solar panels as power supply for space stations or asteroid facility/processing operations. These facilities would be in orbit in the good solar capture area, not too far from the sun.
I am not worried about Thrust 1, this is a facility that has been placed in orbit, built there or towed, so minimal station keeping is needed.
I am interested in building large solar arrays to power the facility and the processing operations. So I want solar panels to produce more than just minimal power to extend minimum operational levels. I want excess power, if in orbit of a planet let's microwave beam the excess down to the planet for free energy to the grid. In non-orbital facilities I want enough power to give power for a manufacturing facility, ore processing. or any other operation I want to operate in the asteroid.
You can do hand wavey descriptions of massive solar arrays visible as the player's ship approaches the facility. But some hard crunchy numbers just to make a design printable for a description would be good.
I am not worried about Thrust 1, this is a facility that has been placed in orbit, built there or towed, so minimal station keeping is needed.
I am interested in building large solar arrays to power the facility and the processing operations. So I want solar panels to produce more than just minimal power to extend minimum operational levels. I want excess power, if in orbit of a planet let's microwave beam the excess down to the planet for free energy to the grid. In non-orbital facilities I want enough power to give power for a manufacturing facility, ore processing. or any other operation I want to operate in the asteroid.
You can do hand wavey descriptions of massive solar arrays visible as the player's ship approaches the facility. But some hard crunchy numbers just to make a design printable for a description would be good.
DickTurpin
Banded Mongoose
Linwood said:
Since the cost of the solar panels is included in the ship cost, annual maintenance already includes the panels.
Sigtrygg
Emperor Mongoose
You could look at the real world numbers and convert and extrapolate. A solar cell on a satellite in orbit around the Earth gets 1361 W per square metre incident radiation, the efficiency of the cell will reduce this - current tech is between 20%-40%PsiTraveller said:
Let's go with the best efficiency and say a TL8 solar array can generate 500 W per square meter - 0.5kW per square metre. What is needed is a conversion to MgT EPs.
Since I do know the conversion rate for CT (250MW per EP) if I go with that 500,000 square metres of solar array are needed (the solar arrays on the ISS are each about half as efficient as the best we could make today and have an area of 375 square metres each).
AnotherDilbert
Emperor Mongoose
Plus a safety margin, since solar panels degrade in space¹, that would be something like a million square metres per EP.Sigtrygg said:
¹ https://en.wikipedia.org/wiki/Space-based_solar_power#cite_note-39
Sigtrygg
Emperor Mongoose
That's with ten year old technology, and I don't think you need to double your array size just to cope with a 0.25% loss per year.AnotherDilbert said:
Let's assume a TL8 panel also includes a coating to lessen this degradation, and at TL10+ the materials are intrinsically resistant to this degradation.
Now to advance the TLs:
higher TLs would bring more efficiency and more durable materials, how about 750 W per square metre at TL10 and 1000W per square metre at TL12
AnotherDilbert
Emperor Mongoose
0.25% is on Earth, much more in space. In the example a panel degraded by 14% in seven years, which would be about 58% in 40 years, hence a safety margin of 200% would leave a life-length of 32 years. We generally assume spacecraft systems have better life-lengths.Sigtrygg said:
Quite possibly, but I don't think we are quite there yet.Sigtrygg said:
Sigtrygg
Emperor Mongoose
Yup, I misread the footnote.AnotherDilbert said:
Still what I am proposing as TL8 is the equivalent of the peak of out current technology and as I say a protective coat, perhaps one that requires refurbishment during annual maintainance
A TL7 solar panel would be 250 W per square metre and suffer for the 10% degradation per year.
I peg current Earth TL as 7.7 - working fusion power, grav vehicles and man portable laser weapons are still to be declassified
