Author Topic: theoretical limits of SEP  (Read 844 times)

Offline Vultur

  • Senior Member
  • *****
  • Posts: 2189
  • Liked: 926
  • Likes Given: 184
theoretical limits of SEP
« on: 08/09/2024 02:35 am »
So I was thinking about this... with modern thin film cells (which can be made as thin as 2-3 micrometers) how good of a specific power could you get for really powerful SEP systems (like the VASIMR 39 days to Mars stuff)?

If you could put thin film solar cells on a solar sail type backing, and deploy it like a solar sail, it seems like you could get enormous areas at very low mass (if density is silicon's 2.5 g/cm^3, 3 micrometers thick means about 7.5 tons per square kilometer, unless my math is wrong).

Could you really get tens to hundreds of megawatts of thrust out of VASIMR or other electric propulsion systems? (1 square kilometer of solar cells at even 10% efficiency should be about 136 megawatts at Earth orbit, maybe 50MW at Mars).

Online InterestedEngineer

  • Senior Member
  • *****
  • Posts: 2699
  • Seattle
  • Liked: 2090
  • Likes Given: 3406
Re: theoretical limits of SEP
« Reply #1 on: 08/09/2024 03:17 pm »
So I was thinking about this... with modern thin film cells (which can be made as thin as 2-3 micrometers) how good of a specific power could you get for really powerful SEP systems (like the VASIMR 39 days to Mars stuff)?

If you could put thin film solar cells on a solar sail type backing, and deploy it like a solar sail, it seems like you could get enormous areas at very low mass (if density is silicon's 2.5 g/cm^3, 3 micrometers thick means about 7.5 tons per square kilometer, unless my math is wrong).

Could you really get tens to hundreds of megawatts of thrust out of VASIMR or other electric propulsion systems? (1 square kilometer of solar cells at even 10% efficiency should be about 136 megawatts at Earth orbit, maybe 50MW at Mars).

Anyone invent a radiator that is that light?

The best ion engine out there is 66% efficient at converting electricity energy to thrust energyt.  That means there's a lot of heat to dissipate.  Yes, a lot of it goes out the back as heated ions, but some of it (say 10%) needs active cooling.

How much does 10MW of radiator mass?


Tags:
 

Advertisement NovaTech
Advertisement
Advertisement Margaritaville Beach Resort South Padre Island
Advertisement Brady Kenniston
Advertisement NextSpaceflight
Advertisement Nathan Barker Photography
1