3. Water, water everywhere…
Per day, six on-orbit crew require:
• 13.2 liters for drinking, eating, and hygiene
• 6 liters for oxygen generation
• 1.8 liters for the toilet
• 1.6 liters for payloads and EVA needs
Total on-orbit needs are 8525 liters (over 2,200 gallons) per
year.
Current systems on board can provide 77% of the water
required through recycling of urine and condensate.
4. …so let’s all have a drink.
• The Sabatier system generates water by
reacting waste carbon dioxide from the
crew with waste hydrogen from the
oxygen generator
CO2 + 4H2 → 2 H2O + CH4
• Through this reaction, Sabatier can
improve the water recovered to over
85%
• Sabatier is also needed for future
exploration
– ISS as a test bed for exploration
– Possible commercial applications
5. The ISS is ready for Sabatier
• The ECLSS systems were designed to function with or without
Sabatier.
– The Oxygen Generation System (OGS) is “scarred” for a Sabatier system
– The Carbon Dioxide Removal Assembly (CDRA) delivers waste CO2, and the OGS delivers
waste hydrogen
6. Sabatier is ready for the ISS
• At the outset of the contracting process,
the Sabatier system R&D was advanced to
the point of an Engineering Development
Unit.
• All of the interfaces with ISS were clearly
defined, allowing for rapid development
• The contractor, Hamilton Sundstrand, has
significant hardware experience.
• The ISS continues to perform as a testbed
for biological, physical, engineering, and
scientific research- acquisition testing was Paul Sabatier (1854 – 1941)
the next step.
7. A New Kind of Service Contract
• NASA only pays for water on-orbit, not for the
hardware.
• More like a utility bill than a general contractor bill
• Minimizes NASA risk because payment is only for the
service when it is available
• Fixed price for the service defines NASA maximum
commitment and puts the contractor’s “skin in the
game” throughout the entire life cycle
• Minimizes NASA involvement in design and
development
• The contractor only gets paid when and if it works
• Demonstrates another type of contract that moves
closer to commercialization of space
• Look-back penalty is either 0% or 100%
• All payments up to checkout are returned:
1. For completion of Safety Review Panel Phase 1 & 2
2. For completion of Performance and Verification Review
3. For completion of On-orbit Checkout
8. A Service Contract is Not Right
For Every Application
• Technical development risk for the developer needs to be
appropriate
– Within their expertise and experience
– Critical to the companies
• NASA needs to be willing to accept delayed performance or
failure
– Mitigated by above
• NASA must be fair and pay if NASA defaults on the deal
– If NASA cannot launch, NASA still pays
– If NASA cannot define or provide interfaces, NASA still pays
• Needs to be some upfront payments
• Fee will be higher than cost plus, but overall cost lower
9. A New Way for the Future
As spaceflight becomes increasingly
commercialized, service contracts will be
more desirable for “routine” needs than
cost-plus-contracts
