For many people, electric cars seem like the obvious automotive future. After all, according to the US Department of Energy, gas cars are only 17%-21% efficient versus 59%-62% for electric cars. Sales of plug-in vehicles are up 33% in the first half of 2014, and vehicles like the Nissan Leaf keep setting new sales records. 

Meanwhile Tesla Motors is planning on increasing its annual sales rate to 100,000 cars by the end of 2015 and 500,000 cars by 2020 while investing billions into building the world's largest battery factory to make these ambitions a reality. 

Then there's the issue of oil, which is a non-renewable resource. Surely the world will run out of oil sometimes within the next 50 to 100 years and force us all to switch to electric cars, right? Well, there are several reasons to believe that gas-powered cars won't give up without a fight, and new technological innovations mean your children and grandchildren might still be driving gas-powered cars 50 or even 100 years from now.

Earth is awash in oil
In 1956 US geologist M. King Hubbert predicted that US oil production would peak in 1970 and then go into a permanent decline. Until new applications of oil recovery technology such as hydraulic fracturing and horizontal drilling took off in the last few years, Mr. Hubbert had been correct.

Us Oil Production Graph

However, thanks to the shale oil/fracking revolution, the US just achieved 11 million barrels/day (mbpd) of oil production in the first quarter of 2014, not only smashing the 9.643 mbpd record set in 1970, but becoming the world's largest oil producer in the process. 

But surely that kind of production growth can't last, right? After all, with oil reserves finite, the faster we pump it out of the ground the faster we run out. Thus the oil boom should actually be accelerating the rate at which we are forced to switch to electric cars. 

To answer that let's put existing oil reserves into context. According to the Oil Depletion Analysis Center in London, the world has thus far produced a cumulative total of 1.2 trillion barrels of oil. Meanwhile the US Energy Information Administration estimates the world's shale oil reserves at 3.357 trillion barrels. Throw in an estimated 2.5 trillion barrels of Canadian tar sands plus conventional reserves and the world has well over 6 trillion barrels of oil left in the ground, about five times what mankind has produced thus far. 

This is not to say that all of this oil is presently economical or technically recoverable, and the environmental implications of using that much oil could be dire indeed. However, I want to make it very clear that the world is not running out of oil anytime soon. 

A well-oiled machine
Automakers are working tirelessly to innovate and maximize the efficiency of the internal combustion engine and cars in general. For example, Ford is making its newly redesigned F-150 pickup truck with 95% aluminum body panels, resulting in 700 lbs of weight savings. Its 2.7-liter turbocharged six cylinder engine allows for 8,500 lbs of towing yet still results in improved fuel efficiency.


Three-time engine of the year award winner Source: Ford Motor Company

Ford's other automotive innovations include industry leading engines. For example, its 1-liter ecoboost 3-cylinder engine just won engine of the year for the third consecutive year according to Engine Technology International magazine.

Ford is also partnering with GM to develop new, ultra efficient 10-speed automatic transmissions. These are expected to improve performance and efficiency in smaller vehicles.

Other automakers are following Ford's example when it comes to maximizing efficiency. For example, Jaguar Land Rover has invested $68 million into its new high-efficiency Ingenium family of engines. 

This will allow the company's upcoming XE sports sedan, which is 75% aluminum, to achieve an estimated 59 mpg based on the new European driving cycle.

Jaguar Xe

Source: Jaguar Land Rover of North America LLC

Meanwhile Volvo is working on a new family of engines dubbed Drive E, which it plans to put into its all new 2015 XC90 full size SUV. A 2-liter 4-cylinder engine will be combined with both a turbocharger and supercharger, as well as a plug-in hybrid option and new eight speed automatic transmission to achieve: 400 horsepower, 490 lbs-feet of torque, and an estimated 117 mpge in the European driving cycle.

Foolish bottom line 
Let me be clear that I am a heavy proponent of electric cars, mainly for efficiency and long-term economic reasons. I believe electric cars will steadily increase their market share over the coming decades and eventually replace gas cars entirely.

However, respect should be paid to the thousands of engineers and business leaders around the globe who are working tirelessly to squeeze every last ounce of efficiency from the internal combustion engine. Given the fact that the world is awash in both oil and vehicle innovations, it's very possible that people may still be driving gas-powered vehicles 50 or even 100 years from now.

Adam Galas owns shares of Tesla Motors. The Motley Fool recommends Ford and Tesla Motors. The Motley Fool owns shares of Ford and Tesla Motors. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.