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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". (The word "gasoline" does not actual refer to any gaseous state, but derives from brand-name fuel of a man called John Cassell that, at times, had also been called "Cazeline" or "Cazelline". The term "petrol"/"petroleum" used elsewhere derives from processed mineral oils ("petra", Latin for "rock"), althugh "Petrol" has also been a registered brand-name for another business's motor-fuel product.)

Electric motors, which were long considered to be impractical for most forms of transportation, although as early as 1885 were an actual form of motor-car engine to which the fledgling internal combustion engine had to compete. Despite, over most of the last century, electric motors being sidelined in everyday car design, modern forms 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 may be very clear which side of the debate White Hat is promoting. On the other hand, it may indicate that one of the things we might consider a pro in electric motors (the instantaneous power now available, exceeding that of many non-electric engines) he would consider a problem - perhaps more accurately, a problem with the drivers of such vehicles, recklessly using the enhanced capabalities to accelerate at all opportunities, whether safe to do so or not.

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. Even when considering inefficiencies in the source production and transmission and storage and release of energy included, battery driven electric vehicles are generally more efficient than internal combustion propelled vehicles[1].

• "More powerful". Electric motors are indeed able to deliver a lot of power from a small motor if an ample energy supply is available, and can do so 'on demand' often far quicker than with a fuel-powered engine that has to put its power through a gearbox in order to service a wide range of road-velocities from standstill to the eventual top speed. Due to battery limitations, short or partial runtime use cases, such as dragsters, hand tools, yard tools, toys and electric scooters, net the most benefit from the small size of a high powered electric motor.

• "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. This might legitimately be considered a problem, though, when surprisingly quiet vehicles are now sharing the roads, when everyone is used to a rapidly approaching vehicle providing a very noist clue of its approach. In particular, turbo-charger blow-off valves make particular noises that are completly lacking in an all-electric vehicle being driven under a similar performance level.

• "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. Again, the audible clues of gear-changes, whether from automatic or manual systems, are part and parcel of what many people have grown up with, in anticipating what vehicles might need paying explicit attention to.

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 (or a hybrid system which can draw at least some of its power indirectly from a more efficiently and inconspicuously running IC engine), which was impractical until comparatively recently. Other methods, such as hydrogen fuel cells (a form of "combustion" that can be used more directly to form electricity) have been proposed, but remain experimental.

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

• Higher cost of purchase (primarily due to the cost of batteries), although partially offset by lower costs of operation
• Long charging times
• Relatively limited range
• Shortened range in hot weather
• Significantly shortened range in cold weather
• Limited charging infrastructure
• Higher vehicle weight

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

Other pros of electric vehicles aren't mentioned

• Lower costs of operation (partially offset by higher costs of purchase)
• Higher reliability
• Lower maintenance and repair costs
• Lower carbon footprint, at least when charged from a grid that has significant nuclear or renewable sources

Taking White Hat's arguments to suggest 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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