1:1:E:1. Heat
Heating requirements for certain types of hab modules are discussed in another section (1:1:H); these requirements are estimates, based on the specifications of the materials used in construction, but provide a framework for planning. Heat for Aurora modules can be provided by electricity, fuel cell waste heat, or chemical combustion. In practice, multiple sources will likely be used - both for redundancy, and to fine-tune heat input based on need. Possible fuels are listed in the table below. The lower heating value (where combustion products are vented to atmosphere) for each fuel is given, as is its density.
|
Fuel |
LHV (kWh / kg) |
Density |
|
Diesel |
43 |
0.832 kg/L (6.943 lb/gal) |
|
Biodiesel |
37 |
0.88 kg/L |
|
Kerosene |
43 |
0.780 - 0.810 kg/L |
|
Propane |
46 |
--- |
|
Methane |
50 |
--- |
|
Hydrogen* |
119 |
0.8988 kg/m³ (at STP) |
*Hydrogen as a fuel is discussed in its own section
The temperature values used for anticipating heating requirements come from two sources: data collected at the American Byrd station between 1961-19901, and at the Soviet/Russian Russkaya station between 1980-19902. Russkaya is relatively close to the planned Aurora site, and at a similar elevation. Both Russkaya and Byrd are/were located in Marie Byrd Land, but Byrd's remoteness from the coast, and elevation (above 5000 ft), make its temperature data a worst-case-scenario lower limit.
The approach - when planning for energy needs and habitat specs - has been to design for the coldest temperature ever recorded in a given location. In the case of the proposed Aurora site in the Fosdick Mountains, that temperature is -47° C, measured at Russkaya in 1985.
If fuel cells are placed inside habitats' thermal envelopes, the waste heat they generate when producing electricity can contribute to overall heating requirements. The electrical energy generated by fuel cells also heats buildings, since after being used by devices, most of it is radiated as infrared [because of thermodynamic inefficiency].
See also: Heat subsection in Emergency Procedures (1:1:EP)
1 Byrd climate data, via NOAA
ftp://ftp.atdd.noaa.gov/pub/GCOS/WMO-Normals/ANTARCTICA/AM/89125.TXT
2 Russkaya climate data, archived from AARI https://web.archive.org/web/20060525125710/http://www.aari.nw.ru/projects/Antarctic/data/data.asp?lang=0&station=5
Russkaya Information Page archived from AARI, May 2006