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Electric vs Gas

Title text: An idling gas engine may be annoyingly loud, but that's the price you pay for having WAY less torque available at a standstill.

Explanation

This explanation may be incomplete or incorrect: Created by a HYDROGEN INTERNAL COMBUSTION ENGINE RUNNING A GENERATOR. Do NOT delete this tag too soon.

Internal combustion engines are the most common technology used to propel vehicles. In US vernacular, the most common motor fuel is known as "gasoline", or "gas" for short, leading to these engines being referred to as "gas engines".

Electric motors, which were long considered to be impractical for most forms of transportation, are rapidly rising in popularity, and now constitute 18% of all global vehicle sales. Randall has long been a strong proponent of electric vehicles.

In this strip, White Hat claims to be comparing the pros and cons of electric motors and gas engines. The joke is that every point he makes goes in favor of electric motors. Despite it being posed as a dilemma, it's very clear which side of the debate White Hat is promoting.

The strip offers the following points in favor of electric motors:

• "Cleaner and more efficient". Internal combustion engines produce and vent harmful combustion products, while electric motors produce no byproducts. The efficiency of both gas and electric motors vary, but the typical vehicle in the US converts around 25% of available energy into motion, while the typical electric vehicle is in the neighborhood of 80%. (It should be noted that all of this refers to the motors only, and ignores how the fuel and electricity are produced).

• "More powerful". While both types of engines can be built for very high power, electric motors can often carry more power in a compact design.

• "Annoyingly loud". Internal combustion engines, by their nature, produce significant noise. Despite noise attenuation measures (such as mufflers), they contribute significantly to urban noise. Properly designed electric motors are nearly silent.

• "WAY less torque available at standstill". Internal combustion engines need to continually operate within a specific range of rotational speeds, which means that a complex system of transmission gearing is needed to convert this motion into the specific speeds needed at the wheels. When starting from a stand-still, this means that torque must be applied to the wheels relatively gradually to avoid stalling the engine. Electric motors, by contrast, generally produce their peak torque when at a standstill. This results in electric vehicles having significantly better acceleration and engine responsiveness.

It should be noted that White Hat is deliberately confining his arguments to electric vs gas motors rather than electric or gas-powered vehicles. Doing so ignores the basic reason why internal combustion vehicles have long dominated transportation: hydrocarbon fuels are a very dense and fairly easy to handle form of energy storage. Providing electrical power to a moving vehicle requires a large number of high-capacity batteries, which was impractical until comparatively recently (other methods, such as fuel cells, have been proposed but remain experimental).

A more comprehensive comparison would include the cons of electric vehicles, including:

• Higher cost (primarily due to the cost of batteries)
• Long charging times
• Limited range
• Limited charging infrastructure

Advancing technologies may change how serious these cons are, but they currently remain genuine issues.

White Hat's argument that electric motors are superior in every way is likely true, if we consider only the motor itself. This is evidenced by the fact that gas motors are virtually never used in applications where a reliable source of electricity is available to run an electric motor. However, if we consider the entire system of motor, power, power storage, and the costs of producing the vehicles and their power sources (i.e., refining the fuel or producing the electricity) the matter becomes significantly more complex.

Transcript

[White Hat, with his palm raised, is talking to Cueball.]

White Hat: Electric motors and gas engines each have their pros and cons.

White Hat: On one hand, electric motors are cleaner and more efficient. On the other hand, electric motors are more powerful.

White Hat: So it's hard to say which is better overall.

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