Difference between revisions of "Electricity"
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==Distribution and transportation== | ==Distribution and transportation== | ||
Electrical energy can be distributed using either Alternating Current (AC) or Direct Current (DC). On Earth AC current is used for most large scale systems, such as power grids and general electrical distribution. DC current has seen renewed use after the development of power electronics, that have led to the construction od DC power lines and DC converters for inter grid connections. | Electrical energy can be distributed using either Alternating Current (AC) or Direct Current (DC). On Earth AC current is used for most large scale systems, such as power grids and general electrical distribution. DC current has seen renewed use after the development of power electronics, that have led to the construction od DC power lines and DC converters for inter grid connections. | ||
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| + | Electrical distribution on Earth makes extensive use of the concept of grounding, as the Earth is generally considered a good conductor due to the presence of water in the soil. On Mars, however, the soil conductance is not necessarily good and separated grounding systems may be required. | ||
==Uses of Electricity== | ==Uses of Electricity== | ||
Revision as of 17:17, 20 April 2019
Electricity is the general term used to describe a number of electrical phenomena, such as Electrical power, electrical current and electric potential. It is associated with magnetism. It plays an important part in almost every modern technology. Electrical power can be transmitted easily a distance via conductors, such as metallic cables. A settlement on Mars cannot be imagined without electricity.
Contents
Primary Generation
Electrical power can be generated from a number of energy sources.
Electricity can be produced locally or centrally, or in a mixture of the two systems. Solar energy tends to be distributed, while nuclear energy tends to be centralized. Solar energy efficiency is independent of the size of the installation, and has lower losses when the user is close to the source. Nuclear energy efficiency depends on the temperature of the nuclear core and require minimum amounts of nuclear material to go critical and produce energy. Secondary systems for nuclear reactors, such as turbogenerators are more efficient when they are larger.
Solar energy
Photoelectricity is the direct conversion of photons to electricity. On Mars, this has already been used extensively for most of the solar probes and rovers.
Nuclear energy
Nuclear reactions in nuclear materials produces heat, that can be converted into electricity either directly or using thermal processes and mechanical energy.
Thermoelectric generators
A thermoelectric generator produces electricity from differences in thermal energy between two or more areas.
Photovoltaics from very hot cores (fourth generation nuclear)
This is the same process as photoelectricity from the sun but gets its photons from a very hot nuclear reactor core that liberates most of its energy in the form of photons.
MHD generators
Magnetohydrodynamic generators use the passage of a hot conducting gas in a magnetic field to generate an electrical current. MHD generators are generally considered as a topping stage to conventional turbogenerators.
Turbogenerators
A combination of a turbine and a generator, usually an alternator, to produce electricity. The generator uses the interaction between magnetic fields and conductors to generate an electrical current. A Dynamo can be used as generator for DC current. However, this requires a mechanical commutator that is subject to wear.
Piezoelectrics
Piezoelectricity is the generation of electricity as a direct result of mechanical deformation.
Secondary generation
Electrical energy can be converted into other form of energy for storage, or stored directly in magneto electrical fields in inductances and capacitances. See Energy storage. It can then be produced in a number of ways; electrochemically or mechanically.
Distribution and transportation
Electrical energy can be distributed using either Alternating Current (AC) or Direct Current (DC). On Earth AC current is used for most large scale systems, such as power grids and general electrical distribution. DC current has seen renewed use after the development of power electronics, that have led to the construction od DC power lines and DC converters for inter grid connections.
Electrical distribution on Earth makes extensive use of the concept of grounding, as the Earth is generally considered a good conductor due to the presence of water in the soil. On Mars, however, the soil conductance is not necessarily good and separated grounding systems may be required.
Uses of Electricity
Electricity can be directly used to produce
- Heat
- Light
- Movement of machine parts.
Significance for a Martian colony
Inevitabilities
For some settlement applications electricity can not be avoided. This is true for radio link and night time lighting.
Alternatives
Although there is some comfort in using electricity for a variety of applications, there are on the other hand some disadvantages to be considered. The storage of large amounts of electrical energy is a problem. Moreover, every transformation causes some loss of energy. The following alternatives may provide an advantage:
- Movement of machine parts can alternatively be created by muscle work, pneumatics or hydraulics. Muscle work is, for a certain degree, always available. Combination with physical exercise should be considered. Compressed-air is an easy storage for pneumatic energy.
- Heating can be avoided with a thick thermal insulation. At best the human metabolism and the lighting cause enough heat for a comfortable room temperature.
- Automation can be implemented with pneumatics.
