Readings:

Time: 08:00
Inside Temp: 74 deg F/ 23.3 deg C
Outside Temp: 33 deg F/ .5 deg C
Relative Humidity: 67%

Time: 12:00
Inside Temp: 78 deg F / 25.6 deg C
Outside Temp: 50 deg F / 10 deg C
Relative Humidity: 65%

Time: 20:00
Inside Temp: 59 deg F/ 19 deg C
Outside Temp: 43 deg F/ 6.1 deg C
Relative Humidity: 61%

Hab (taken at 19:00)
Minimum Temp (& RH): 63 deg F/ 17.2 deg C/ 23%
Maximum Temp (& RH): 76.6 deg F / 24.8 deg C / 34%

Today:

Plants watered; salad machine, nursery, and surface plants all thriving. All tanks at normal levels.

GreenHab Summary

• Accomplishments
• Weather station
• Salad machine
• New screens and drain guards in Tanks 2 and 4
• Photo documentation of sensor placements
• Added surface plants
• Added ozone generator to Tank 5
• Added aerators to Tanks 1 and 3
• Covered sides of Tanks 2 and 3 to prevent algae growth

Water Usage: The GreenHab system does seem to do its job quite nicely. The main concern is to balance fresh water usage/conservation, while ensuring that enough water is used each day in the Hab to flow through the GreenHab system and keep it full and functioning well. An easy way to ensure that enough water is used (min. 20/max. of 30 gallons/per day) is to have each crew take two showers per day and wash dishes twice per day. Our crew normally used closer to 30 gallons/day because we cooked a lot and we found that it was not possible to do dishes merely once per day (not enough clean dishes or space to make the next meal!). This would be our recommendation for future crews.

If not enough water goes through the system, the tanks become depleted and thus Tank 5, which is at the end of the line, would not be full enough to replenish the TST. If too much water goes through the system, a normal amount of toilet flushes wouldn't be enough to draw from Tank 5 fast enough, and thus Tank 5 would overflow. This figure of 20-30 gallons/day usage is simply approximate. I think to throw off the system, you would really need to use either far less or far more water than normal. The system is good at righting itself if the levels are just somewhat off. We discovered this after accidentally depleting Tank 4 twice...we were worried that it would take a long time for Tanks 4 and 5 to get back up to normal levels, but you just take a few extra showers to move extra water through the system, and things right themselves.

Need for Automation: Two areas in the GreenHab could easily be automated to eliminate the need for a crewmember to be physically present three times per day: 1) the recirculation pump from Tank 4 to Tank 1 can be put on a timer to run for five minutes, three times per day; and 2) the switch from Hab power to solar power and back each morning and evening can be put on a photocell. With these two functions automated, a crewmember can simply visit the Greenhab once per day to visually inspect the tank levels, assure that the aerators, pumps, trickling filters, and fans are operational, and tend to the nursery plants. The newly automated TST refill, for example, has been great.

Roof Leaks: Needs to be fixed; see previous reports.

Wiring: While we did tack down some loose wires per Crew 27's recommendations, there are many exposed connections and no cover on the circuit breaker box. Especially now that the electrical diagram has been completed by Crew 27, now would be the time to better house these elements.

Diagrams: Our thanks to Crew 27 for creating the Water Flow and Electrical Diagrams for the GreenHab. They proved invaluable to us and to the Engineering team, and will likely be just as useful to future crews as well.