# Solar Panels for refining fuel

#### PsiTraveller

##### Cosmic Mongoose
I am trying to work out a solar panel based economy for asteroid living.

Assume the space family Robinson gets a Crown Grant to settle/homestead an asteroid. They find a 100 000 ton asteroid in a good solar zone, towing it into place if need be and settle in to carve out a home for themselves.

If the panels are sized to asssume no power plant then they need to meet basic systems and thrust 1. that would be 20000 power points for basic systems and 10000 points for thrust 1, 30 000 power points total.
Assuming TL 12 fusion at 15 points a ton that would be 2000 tons of power plant. 1o percent of that would be 200 tons of Solar Panels. (This raises a question as to what if we assumed TL 15 power plant at 20 points a ton, the same solar panels would now only need 150 tons of panels to provide the power? What about TL 8 Fusion aT 10 Point a ton.)

There seems to be a need to change the cost of panels to be TL specific, higher tech levels produce more power per ton.

So Assume the Robinsons don't actually have all the 100 000 tons of asteroid all hooked up, they are mining out the asteroid to build a home. They are wealthy and did buy all 200 tons of solar panels, as well as 10 tons of batteries with 60 power points per ton.

The description of solar panels says range and endurance is infinite as long as no manoeuvering or refining fuel. What is so power intensive about refining fuel? The power cost is 1 power point, even assuming 6 minute rounds of power demand that is 10 points an hour. One ton of battery could hold power for 6 hours, 24 hours power could be held in 4 tons of batteries.

It seems to me that a single ton of panels produces a flow of power equal to 10 tons of power plant, or 150 power. Looking at the math I have to think that solar panels and battery banks would be powering a lot of systems on asteroids.

Am I missing something here? Or are solar farms going to be popping up and powering industrial platforms in most systems?

If there's fusion in the game setting, there is also solar panels that work probably. See hand-waving.

What is the need for refined fuel for this situation?

The design sequence should divorce solar panelling size and output from hull volume, and give a set amount per volume; it is of course at the moment very dependent on the output of the installed power plant, which can vary in price and output depending on technological level and customization.

Having said that, solar panelling would be less capital intensive and needn't require a trained engineer, since a reactor, fusion or fission, could be subject to catastrophic failure.

On the other hand, solar panelling seems to be magically efficient.

Solar panels do require engineers to maintain them as its a major power system, which can be accomplished through automation.

The hull requirements are only for the power calculation not a limit on the solar panel size, just need to note you can't maneuver with panels deployed.

PsiTraveller said:
If the panels are sized to asssume no power plant then they need to meet basic systems and thrust 1. that would be 20000 power points for basic systems and 10000 points for thrust 1, 30 000 power points total.
You can't activate the M-drive under solar power so I assume solar power don't provide power for the M-drive, hence only providing basic power (20 000 Power in this case.)

HG only provides a simple rule-of-thumb for solar power backup systems for ships, not permanent installations for space stations.
HG said:
Solar Panels
Extendible solar panels provide backup power for a ship’s power plant.

To give the power per volume indicated the "panels" have to be gossamer-thin films suspended in space. They would be shredded by anything touching them. That would make them unsuitable as the only power plant for an installation.

They would only give the rated power in the Hab zone, power would multiplied by 25% (or size by four) for each doubling of the distance to the local star.

PsiTraveller said:
Am I missing something here? Or are solar farms going to be popping up and powering industrial platforms in most systems?
Basically no, solar power works excellently and reliably in space.

You would need a much sturdier installation than described by HG to be your primary power source, and you would need battery backup if you risk planetary shadowing, e.g. if you are in orbit around something.

The solar panels we have today degrades rather quickly in space from what I have heard, so the panels might have to be replaced regularly, say every decade or so...

Power is life or death in space and both fusion and solar are fairly cheap so it might make sense to install both for safety in space stations.

Which begs the question, why the provision for one gee thrust?

The tonnage consumed by enough solar panels required
to power a ship is equal to 10% that of the main power
plant, to a minimum of 0.5 tons. Solar panels cost
MCr0.1 per ton
If the panels are fitted to a ship without a power plant,
then assume the (non–existent) power plant is sized
to the ship’s basic systems and a Thrust 1 manoeuvre
drive. A ship equipped with solar panels consumes
power plant fuel at one–quarter the normal rate so long
as it is only engaged in minimal manoeuvring and does
not fire any weapons. Minimal manoeuvring does not
include long periods at full thrust, so solar power alone
is useless for most commercial and military vessels.
No power plant fuel is consumed, and endurance is
considered infinite, if the ship is not manoeuvring or
refining fuel. Jump drives cannot be engaged with solar
panels deployed.

I understand how the intent is for ships and the roleplaying of extending fuel supply while on a mission.

The space station chapter puts the option of space based infrastructure into space. This could be space refining, asteroid mining/processing facilities and manufacturing capabilitiy. These systems need a power source, and a solar panel system or solar/battery combination to ensure steady flow off power to whatever machinery you are operating seems to be a good investment. A ton of solar panels puts out 150 power (assuming the 10 percent number is valid). 10 tons of power plant (TL 12) puts out 150 power, which is replaced by 1 ton of solar panels. 150 power is a lot of power, more than enough to run a fuel processor, so why the restriction?

I am thinking of large operations placed close to a sun, taking in the free solar energy and being the manufacturing base for the system. Place the asteroids perpendicular to the ecliptic to not block the sunlight heading for the planets. There is a lot of energy available, which means there are profits to be made. I think it is an area that could be fleshed out in the rules to add more options for players and GM's

The rules for solar systems are definitely a bit hazy. So long as you aren't in a hurry there's no logical reason why a ship cannot be fully solar-powered. Energy derived from a fusion plant is no different than energy derived from a solar panel. The only difference is fusion is much more compact and provides more output/ton than solar panels.

The rules also don't cover slower speeds. Stooging around at .1G via solar power is basically the same as getting in a small sail boat and sailing across the ocean rather than taking a plane.

As for stations that are powered by solar panels, if you don't want to install batteries just put it in a polar orbit or park it at a lagrange point that has full solar exposure.

Given the restrictions on maneuvering with solar panels, it appears to be the assumption that the fuel processor is being used in a skimming operation.

As to the short bursts, it might be like Extended Arrays where you can't maneuver while the array is deployed but you can retract then move( Next Turn).

That makes sense, and I am thinking of a stationary asteroid with a refining module and drones bring in unrefined fuel. So I feeel fine in ignoring the line from High Guard.

Of course a ship could skim, fill tanks, then set up in a lagrange point and start processing. It might add some time to the process, but save fuel. With panels producing so much energy the restriction does not make a lot of sense.

Considering you need partial or better streamlining to do skimming, however stations have the refinery which allows for skimming from orbit via skimming drones.

Yes, definitely thinking drones to storage tanks, or skimming ships to tanks for processing into Jump fuel.

An asteroid station with solar panels and a stable energy supply can power all sorts of industry. Jump fuel is an obvious one, hydrocarbon fuel if you want to reconfigure the fuel processor to produce diesel or gasoline from methane. Di-methyl ether is also an option.

Then you get into the space based crystal and zero g materials production. A solar array could power a refinery and production unit easily.

Spaceships: Engineering, Sunbathing and It's Not Easy Being Green

If the panels are fitted to a ship without a power plant, then assume the (non–existent) power plant is sized to the ship’s basic systems and a Thrust one manoeuvre drive.

If the panels are fitted to a ship without a power plant, then assume the (non–existent) main power plant is sized to deliver a performance rating of one.

Can you spot the difference?

The top sentence comes from the revised edition, and for our purposes, that for every ten tonnes, you have an appropriate rated solar panel that will deliver three scotts, in lieu of an a shipboard generator).

Though, which generator?

Let's go with my favourite technological level, nine, since that's when you introduce manoeuvre drive technology.

Let's take an early fusion power plant, with a default setting of ten scotts per tonne output.

Let's see how all this fits on a thousand tonne hull (mostly to get over the half tonne panelling minimum).

So a one kay hull has a basic power requirement of two hundred scotts, and can needs another hundred scotts to input into the impulse drives.

That means I need thirty tonnes of early fusion power plant to generate three hundred scotts.

Solar panelling is sized to ten percent of the matching power plant, that would mean that I only need three tonnes of solar panelling to generate three hundred scotts at technological level eight.

If we assume that actually any solar panelling can only deliver three quarters of the advertised output, we have four tonnes of technological level eight solar panelling delivering a net output of three hundred scotts, which works out to seventy five scotts per tonne of solar panelling, which is just seventy percent as efficient per tonne as a technological level twenty anti matter power plant; and greener.

Spaceships: Sweat of the Sun, Tears of the Moon and Solar Panelling

Taking this a step further, the expectation seems to be that he vessel can sustain, even if only temporarily, one gee constant acceleration.

That means the power requirement increases by fifty percent, which means a half tonne of solar panelling can run a one hundred sixty six tonne mobile space station.

It's an interesting question why you can only fire up the manoeuvre drives temporarily, and exactly how long can that acceleration be sustained for any length of time is it due to structural integrity, and would we experience the same restrictions if we just lit up the reaction rockets?

It shouldn't prove a problem to attach the solar panelling to the hamster cage mechanism, so that the solar cells can face the direction of the sun at all times, assuming nothing eclipses it.

In this edition, is there a "Maneuver-0" rating for station-keeping (gradual, minor orbital adjustments) only? Or am I thinking of another edition? Some editions say that if there's any maneuver drive installed at all, even if it's only enough for 0.0001 G, that's good enough for station-keeping. That would not require a lot of power, and even a fragile power source like solar panels would work (rather than torn to pieces like it might under even 1 G of acceleration).

If that's not actually in the official rules, you could house-rule it in to make space stations viable with fuel shuttles.

MGT 2ed does have thrust 0 m-drive but the solar power calculation is for solar power as the sole power plant, in effect is the minimum power requirement.

Embed the solar panels in the hull.

Arguably, you won't be able to make a hot landing in an atmosphere, without melting that layer off.

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