Having started from zero last decade, global acceptance of plug-in electrified vehicles (PEVS) is speeding up and in just the past four months the number grew by 20 percent to 600,000 vehicles sold.

This counts only the top-10 countries and their purchases of primarily passenger-oriented, highway legal plug-in hybrids and all-electric vehicles. Of these around 356,232 are battery electric, and 247,700 are plug-in hybrids and they add to an estimated 603,932 PEVs.

The lion’s share began after 2010, but a few thousand were counted from as far back as 2006 in the UK and 2003 in Norway. Excluded are commercial vehicles except for a few small vans. Also not counted are motorcycles, and buses, and this is overwhelmingly a tally of “normal” cars for consumers.

Silver Lining

With only a little more than a quarter million PEVs in American hands so far, it’s evident the country will be late for President Obama’s goal of one million for 2015. And we’ve seen some failures with start-ups, and a U.S. market otherwise stuck in the mud with several “compliance cars” by automakers unwilling or unable to proliferate them beyond limited markets and quantities.

BMW i3.

But despite negative indicators hovering like dark clouds, the silver lining is PEV numbers are adding up not unlike pennies, nickels, dimes and quarters thrown into a jar that eventually tally to a fair amount of dollars.

SEE ALSO: Plug-In Car Sales Cross Global Half-Million Mark

As existing markets and others yet pending purchase PEVs, and as automakers roll out new models from yet-modest efforts, the tide is slowly turning, and momentum ought to increase given growth to date.

To provide a closer perspective, here are various global sales milestones and when they occurred: 100,000, Dec, 2011; 180,000, Dec. 2012; 405,000, Jan. 2014; 500,000, May 2014; 603,932, Sept. 2014.

At the current rate, estimates by Brazil-based alternative energy enthusiast, plug-in car statistician, and HybridCars.com reader, Mario R. Duran shows acceleration continuing.

Duran conservatively forecasts 700,000 global PEVs by December and 1 million by August or September 2015.

Disproportionate Contributions

Among the 10 top-contributing nations, the percentage of PEVs purchased varies considerably.

“China, Germany, the UK and Sweden all have experience ballistic grow this year,” said Duran looking over the percentage of growth. “France is tanked, and Japan slowed down from previous years.”

The PEV market share in the U.S. is 0.71 percent, China’s is 0.22 percent, and if only these could adopt at a rate like some of the standouts, we’d really have significant volumes.

SEE ALSO: Tesla On Track To Sell 50,000th Model S This Month

The heavy lifting is being done by smaller nations, most notably Netherlands at 4.02 percent, and Norway at just around 15 percent.

These small countries have demonstrated political will, implemented infrastructure, and made the cost-benefit equation compelling for plugging in versus staying wedded to conventional petroleum power.

Pennies In a Jar

These are the tallies based on published reports through Sept. 2014:

United States: 259,949
Japan: 95,153
China: 77,205
Netherlands: 40,954
France: 38,605
Norway: 37,824
Germany: 21,256
UK: 17,456
Canada: 9,200
Sweden: 6,771

Just for some perspective, if the number-one EV adopter – the U.S – was adopting at the rate of the most aggressive – Norway – it would be a changed world.

Instead of around 6,000 electric cars bought in the U.S. in September, Americans would have taken home 185,000. And this year, instead of close to 44,000 in the U.S., the grand tally would be 1.85 million – just from January through September.

The actual numbers are around 260,000 PEVs bought by Americans since 2008 out of the just-over 604,000 global total.

And really, it’s an academic discussion and moot point as long as reality is what it is.

The present reality is earlier predictions have not all gone as hoped, but in the main, they arguably have. Growth is happening, synergy is increasing momentum, 0.6 million PEVs now displace conventional cars, and the next milestone will be here before you know it.