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Well, 30 tons of MREs can get a 100-man crew through 500 days of greenhouse construction, assuming robotics/telerobotics do most of the heavy lifting.  The boring menu would motivate the crew to get the greenhouse ice cream factory up and running asap.

That's... 1 kg/m3?  Vastly superior to ISS BEAM.  How do your material properties and layerings compare with BEAM? 

The martian surface presents saltation abrasion, hard UV, electrical discharge, corrosive salts and an uncertain flux of cm-scale iron meteorite bullets.  Maybe you've accounted for these and other problems, but you'd want to be sure your greenhouse could survive them.

A good principle, that. 

What structural mass per m3 do you estimate for your quonset-style greenhouse?  For comparison, an LMT 300-m water-roof dome is notionally a modular titanium polygon / ETFE foil cushion structure.  That structure (including anchoring system) comes in around 0.1 kg/m3.

Well hi, and thanks for running things.  Sane forum.

Max Yield

Sounds good.  Given the expense and difficulty of constructing greenhouse space, superb crops are needed, with careful co-planting for efficient use of space, and many other tweaks for max yield.

Chard is good, yes.  Turnips are yucky. 

In one exercise I roughed out an intensive garden, augmented with prawn-and-tilapia aquaculture.  Scale: 8 acres of garden, 1 acre of aquaculture.  Location: 40 South.  Lighting: 60% PPF light transmission, for 9 months of useful sunlight per Mars year, plus LEDs.  LED supplement and extended growing seasons notionally match yields to terrestrial garden yields (with exception of wheat, per above).

In this scheme the garden and aquaculture produce roughly 210 million calories per Mars year:  self-sufficiency for an initial crew of 100. 

The plots:  (link to full-res image)

I didn't attempt a Perfect Day / Thrive synthetic dairy plant in that scheme, because I can't quantify the plant's yield.  I imagine it could boost calorie production significantly.

Can you recommend some other breakout crops or methods, to make big improvements in yield?  E.g., some especially short-season (<60d) hybrids?

Ferment and Fertilizer

Right, that's what the Buttercup GM yeast does.  Then once it outputs the casein protein, normal dairy processes make cheese and other tasty products. 

I don't know Buttercup yield, the factor that determines viability for a small greenhouse plant.  I'd expect yield to be excellent - after all, it's an optimized commercial GM fermentation process - but I don't have a number yet.

We explored in situ production of calcium, magnesium and other nutrients as bulk fertilizer, at the NasaSpaceFlight forum.  One tech that seemed to meet the need for calcium and magnesium fertilizer was the Calera CO2 sequestration process, aka ABLE:  Alkalinity Based on Low Energy.  It's a commercial process that efficiently extracts calcium and magnesium cations from basalt - a rock which is of course abundant on Mars.

Alternately, a Zero Liquid Discharge (ZLD) plant could also extract those cations from brine, as part of the standard ZLD precipitation sequence:

1.  iron via oxidation & pH increase

2.  magnesium via pH increase

3.  calcium and phosphorous via pH decrease, then alkaline agent

4.  potassium via temperature decrease

Additional potassium and phosphorus could be recovered from stalk-and-greens composting, which would also provide free heat for the Calera reactor.

Nitrate can also be produced efficiently in the greenhouse.  As envisioned, a nitrogen gas-separation membrane is coupled to a small plasma nitrate production plant.

Other methods could be used of course, and you've broached some others in forum.  I just note that these particular ISRU methods could likely produce, altogether and efficiently, over 90% of the fertilizer required for a hydroponic greenhouse.  That's significant only because fertilizer tonnage would be very expensive if shipped as cargo, or else very hard-won if recovered through complex ECLSS waste reprocessing.

Yes, and they noted that CO2 enrichment "makes a slightly higher maximum [photosynthetic] efficiency possible".  They noted some other mods that might also boost yield beyond their own: 

- raising planting density (e.g., from 2000 to 4000 plants/m2)
- optimizing hydroponic water potential and hydroponic root-zone environment
- balanced nutrient uptake
- longer photoperiod for increased nitrogen assimilation
- and of course, higher PPF.  The published figures present yields that have not yet plateaued even at the highest experimental PPF (150 mol/m2d).

See Fig. 8 for the growth rate that's "potentially achievable".  Clearly there's room for improvement, and some methods for attempting improvement.  And who knows, combining these methods with focused genetic engineering might lift growth rate beyond the rate that was potentially achievable back in 1988.  100 million calories per acre might not be possible, but it's not obviously impossible.

Wheat

Under optimal field conditions you can get over 6 tons per acre, but the greatest yield ever recorded was achieved in a NASA high-irradiance experiment.  Bugbee and Salisbury 1988 got 20 tons per acre:  enough wheat for 36,000 loaves.   

That's 69 million calories from one harvest on one acre.  I think that's the yield record for any crop species, and an attainable goal for a settlement attempting calorie self-sufficiency.

A notional greenhouse acre plot:

- 2000 wheat plants/m2
- summer sunlight + 6 MW power, 16 hr/sol, spectrum-optimized LEDs
- curtain-box (red mulch) surrounding plot, to maximize useful PPF and prevent eye damage
- PPF 200 mol/m2d  (~4x typical terrestrial field)

Magnus effect gives greater lift.  In comparison, the proposed JPL Mars copter is a kind of rotor, augmented.  It would mass 1 kg and spin a counterrotating rotor pair having span of 1.1 m. 

With the rotor spinning at 2400 rpm, the copter lifts only itself and a payload of, essentially, a GoPro camera board.  Rotor tips approach 500 km/hr, so there's little freedom to increase rpm or blade length.  Payload is maxed out.

Given the very slight lift of JPL's example copter, I think kbd512 is probably right on that.