This week we continued researching the regenerative fuel cell.
Manufacturers of both fuel cells and electrolyzers have been contacted and questioned on sizing information.
A spreadsheet is being developed in order to do the calculations for the sizing of the system.
After contacting the manufacturers, it was decided that separate fuel cell and electrolyzer stacks will be used instead of the single package due to the efficiency. Also, in sizing the fuel cell, a "middle of the road" approach will be taken. Because the acid and alkaline fuel cells have approximately the same numbers used in sizing, neither of the two will be chosen specifically until later.
The solar cells which are going to be used are the GaAs/Ge. They are the cells which were recommended by Frank Baiamonte from NASA's JSC.
As of right now, the plan is to run off of the fuel cell during lunar night, and the solar array during the day. For sizing, the solar array would need to provide enough power to supply the lander and the electrolyzer (regen. hydrogen and oxygen).
Next: At current status the power group is ahead of schedule. However, new power requirements will need to be obtained due to the increase in mission length. The plan for next week is to begin obtaining these requirements from other subsystems. The lack of this information should not hinder our work at present, however, it could cause a standstill later in the design. The group also plans to continue to develop the spreadsheet for sizing the fuel cell and other components.