Difference between revisions of "Comparison of motors"

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(The appropriate use of the different engines)
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|colspan="9" | ''' Engines using a deflagrative liquid/gas (ie gasoline, hydrogen, ...)'''  
 
|colspan="9" | ''' Engines using a deflagrative liquid/gas (ie gasoline, hydrogen, ...)'''  
 
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|Internal combustion engine || 20-30% || ? || ? || ?? || ? ||
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|Internal combustion engine (Otto)|| 30% || ? || ? || ?? || ? ||
 
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|[[Fuel-powered turbine]] || 70-80%<ref>[http://wiki.answers.com/Q/Thermal_efficiency_of_gas_turbine Gas turbine efficiency]</ref>|| ? || ? || ?? || ? ||
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|Internal combustion engine (Diesel)|| 35-50%<ref>Efficiency range depends on compression ratio, large low-speed diesel engines typically having a higher compression ratio, and thus a efficiency closer to 50%</ref> || ? || ? || ?? || ? ||
 
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|Internal combustion engine || 20-30% || ? || ? || ?? || ? ||
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|[[Fuel-powered turbine]] || 70-80%<ref>[http://wiki.answers.com/Q/Thermal_efficiency_of_gas_turbine Gas turbine efficiency]</ref><ref>Efficiency differs greatly from the type of turbine used though (unrecuperated or recuperated version)<ref><ref>Efficiency greatly depends on size aswell, microturbines ie are but 15 to 30% efficient, see http://www.wbdg.org/resources/microturbines.php</ref>|| ? || ? || ?? || ? ||
 
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|colspan="9" | ''' Engines using electricity'''  
 
|colspan="9" | ''' Engines using electricity'''  

Revision as of 22:49, 19 August 2012

This article compares motors, primarily on their efficiency and usability in a given location.

Comparison of the engine types

Type Efficiency Fabrication requirements Difficulty of production Durability Difficulty of repair Production cost
Engines using a heated/compressed liquid (ie water)
Piston steam engine 15%?  ?  ?  ??  ?
Steam turbine (bladed rotor) 35%[1][2]  ?  ?  ??  ?
Steam turbine (Tesla) 40%  ?  ?  ??  ?
Fuel cell  ?  ?  ?  ??  ?  ?
Engines using a heated/compressed gas (ie air, ...)
Compressed air engine 26%  ?  ?  ??  ?
Stirling engine upto 40%  ?  ?  ??  ?
Engines using a deflagrative liquid/gas (ie gasoline, hydrogen, ...)
Internal combustion engine (Otto) 30%  ?  ?  ??  ?
Internal combustion engine (Diesel) 35-50%[3]  ?  ?  ??  ?
Fuel-powered turbine 70-80%[4]Cite error: Closing </ref> missing for <ref> tag  ?  ?  ??  ?
Engines using electricity
Electric engine (Switched reluctance motor) 70%  ?  ?  ??  ?

The appropriate use of the different engines

A lot of inefficient (fuel-burning) engines generally have very little efficiency and lose most energy in the form of heat. Ie internal combustion (IC) engines lose 70% of their energy in the form of heat, which makes them insuitable for tasks such as transport, ... In applications where this generated heat can be reused (ie for space heating), the 70% inefficiency can be recovered. [5][6]This means that these engines are most suitable as a combined heat and power system, ie for use in greenhouses, ... The same is true with a multitude of different engines (see above).

IC engines

Internal combustion engines can be fed using various fuels; ie diesel and petrol but also biofuels and wood gas. Fuels alternative from diesel and petrol reduce the efficieny of the system since energy is lost in the fuel production. For example, with wood gas, we find that we lose 25% efficiency (production is 75% efficient).

Thus, if ie IC-engines were to be used for inappropriate tasks as transport, the system will attain a efficiency of 3/4_X_30%= 22,5%. The production of the other fuels (ie pure plant oil, produced from waste vegetable oil) may be even less efficient. From an ecologic and a appropriate standpoint, these supplemental losses are irrelevant, and the system used for these inappropriate tasks will still be much more ecologic than by using diesel/petrol for the same tasks, simply because plants are already in the ecosystem where fossil oils are not. However, appropriately seen, we can never justify their use for inappropriate uses as transport, even if it is already better than their same use using fossil fuels.

See also

References