Scientists are working on solving the mystery of deriving hydrogen from fuel in an affordable way to power vehicles.

The Christian Science Monitor says:

Hydrogen has the potential to fuel incredibly environmentally clean cars. But making that fuel hasn’t been so efficient or economical. Pure hydrogen gas does not occur naturally on Earth, so scientists must devise ways to separate hydrogen from naturally occurring compounds, like H₂ O.

Electrolysis, the process of breaking H₂ O into hydrogen and oxygen gases by passing an electric current through water, and other possible methods have been prohibitively expensive or difficult.

But a team of scientists have come up with a different mechanism to produce hydrogen fuel from water. These researchers have created a biomaterial that catalyzes the splitting of the water elements, which they describe in a paper published in the journal Nature Chemistry.

Read more here.

UPDATE     5/28/19

Research continues.  The real potential is to have hydrogen power fuel cells.  Researchers are working on developing the technology to use hydrogen to power fuel cells. The hope is that this technology will replace internal combustion engines. Only water would be released from the tailpipe.

Commercialization of hydrogen fuel has not yet been accomplished.  There are many hurdles remaining before fuel cell systems will be a viable alternative for consumers.”  Cars powered by fuel cells are in prototype stages now.

For more information, see this article:  Can Cars Run on Water?

At this point, the most viable option for car efficiency, including high mileage and low emissions seems to be hybrid gasoline / electric cars.  However, fully electric cars technology continues to gain ground quickly.  The tipping point is approaching.

With Tesla now offering a model with pricing in the range of other quality cars, and a full range of options from most auto manufacturers, we expect that we will soon see an explosion of charging stations.