Quote from: Robotbeat on 06/17/2017 06:50 pmJust use CO/O2 as a fuel system. Then you don't need to mine water and don't need to collect the exhaust.In principle this is a backup system that is only needed in emergencies. On that basis any system should leverage as much existing infrastructure as possible. Since SX have decided on Methalox (and show no signs of changing that decision) the simplest option is to run power generation (either combustion based or FC) with the same reactants, running overnight needs on batteries.
Just use CO/O2 as a fuel system. Then you don't need to mine water and don't need to collect the exhaust.
A system that can burn both CO/O2 and methane O2 would be helpful at the main site. CO/O2 can keep heavy industry running over night and may be more efficient than batteries, when weight and lifespan is included. In emergencies like long dust storms the propellant store can be used.
Good idea. Dual fuel shouldn't be a problem (the on-board generator for the Wrightspeed hybrid truck is a micro-turbine that is designed to run on diesel, compressed natural gas, liquid natural gas, liquid propane, or landfill gasses).
You might want generators at two sites (and away from any batteries) for redundancy/safety reasons. Just as you probably don't want to keep all your propellant in two big tanks. Though such redundancy comes at a cost, of course.
MIT Aims To Bring Nuclear Fusion To The Market In 10 Yearshttp://www.wbur.org/bostonomix/2018/03/09/mit-nuclear-fusionhttps://www.engadget.com/2018/03/09/mit-embarks-ambitious-plan-build-nuclear-fusion-2033/
TL;DR: commercial availability of continuously improving magnetic field density resistant high temperature superconductors. Basically the remaining job is commercializing the specific integration of the commercial off-the-shelf technologies in modern start-up fashion, quickly and efficiently.It seems reasonable to expect these aspirations to be met. This would make these commercial reactor technologies available for the aerospace community to lightweight for airlift and space-lift compatible versions.
One point I've not seen discussed very much is how much baseload vs dispatchable power will be needed on Mars.Given by far the greatest power requirement comes from the Sabatier plant making rocket fuel, I think the answer to this hinges on how amenable our hypothetical Mars-based Sabatier plant will be to shutting down and starting up again. I know that in heavy industry on Earth some industries are very suitable to Demand Side Response, is this the case with the Sabatier plant? What kind of penalties are there to shutting down/starting up? What losses are there, and how agile (fast) can a shutdown/startup be done in this kind of process?
Quote from: redskyforge on 04/10/2018 01:48 pmOne point I've not seen discussed very much is how much baseload vs dispatchable power will be needed on Mars.Given by far the greatest power requirement comes from the Sabatier plant making rocket fuel, I think the answer to this hinges on how amenable our hypothetical Mars-based Sabatier plant will be to shutting down and starting up again. I know that in heavy industry on Earth some industries are very suitable to Demand Side Response, is this the case with the Sabatier plant? What kind of penalties are there to shutting down/starting up? What losses are there, and how agile (fast) can a shutdown/startup be done in this kind of process?I don't know the answer to that, but the ability to reduce power consumption significantly would be desirable, especially if solar was a significant source of electrical power - at night and during dust storms, for example. But you might not need to shut down the propellant plant; reducing output may be sufficient.Minimum baseload is presumably life-support and keeping essential equipment etc running.
Quote from: CuddlyRocket on 04/11/2018 06:06 pmQuote from: redskyforge on 04/10/2018 01:48 pmOne point I've not seen discussed very much is how much baseload vs dispatchable power will be needed on Mars.Given by far the greatest power requirement comes from the Sabatier plant making rocket fuel, I think the answer to this hinges on how amenable our hypothetical Mars-based Sabatier plant will be to shutting down and starting up again. I know that in heavy industry on Earth some industries are very suitable to Demand Side Response, is this the case with the Sabatier plant? What kind of penalties are there to shutting down/starting up? What losses are there, and how agile (fast) can a shutdown/startup be done in this kind of process?I don't know the answer to that, but the ability to reduce power consumption significantly would be desirable, especially if solar was a significant source of electrical power - at night and during dust storms, for example. But you might not need to shut down the propellant plant; reducing output may be sufficient.Minimum baseload is presumably life-support and keeping essential equipment etc running.Not all life support has to be baseload. You could use consumable stores (e.g. O2, water) when you don't have power, then regenerate (by electrolysis, filtration, etc.) them when you do.
Yep. I read on another thread here that the larger your habitat volume, the longer it takes for the O2 mix to become seriously depleted.
Quote from: redskyforge on 04/11/2018 07:22 pmYep. I read on another thread here that the larger your habitat volume, the longer it takes for the O2 mix to become seriously depleted.And I recall also seeing that "air pockets" last far, far longer than people think. http://www.vocativ.com/198502/underwater-air-pocket-yangtze-river/index.html"Hexdall calculated that, in an air pocket the size of a U-Haul moving van, it would take about 79 hours before you lost consciousness."
Quote from: AC in NC on 04/11/2018 09:18 pmQuote from: redskyforge on 04/11/2018 07:22 pmYep. I read on another thread here that the larger your habitat volume, the longer it takes for the O2 mix to become seriously depleted.And I recall also seeing that "air pockets" last far, far longer than people think. http://www.vocativ.com/198502/underwater-air-pocket-yangtze-river/index.html"Hexdall calculated that, in an air pocket the size of a U-Haul moving van, it would take about 79 hours before you lost consciousness."Yes, but its not the lack of oxygen thats the problem. Its the carbon dioxide build up that will get you in trouble first long before you run out of oxygen.
The dominant application for CO2 scrubbing is for removal of CO2 from the exhaust of coal- and gas-fired power plants. Virtually the only technology being seriously evaluated involves the use of various amines, e.g. monoethanolamine. Cold solutions of these organic compounds bind CO2, but the binding is reversed at higher temperatures:CO2 + 2 HOCH2CH2NH2 ↔ HOCH2CH2NH3+ + HOCH2CH2NHCO2−
Quote from: Steve D on 04/11/2018 09:45 pmQuote from: AC in NC on 04/11/2018 09:18 pmAnd I recall also seeing that "air pockets" last far, far longer than people think. Yes, but its not the lack of oxygen thats the problem. Its the carbon dioxide build up that will get you in trouble first long before you run out of oxygen.That's exactly what that article says.
Quote from: AC in NC on 04/11/2018 09:18 pmAnd I recall also seeing that "air pockets" last far, far longer than people think. Yes, but its not the lack of oxygen thats the problem. Its the carbon dioxide build up that will get you in trouble first long before you run out of oxygen.
And I recall also seeing that "air pockets" last far, far longer than people think.