Hydrogen make up about 92% of all mass in the entire universe. It’s everywhere. Ask any astronomer. All that interstellar gas? Hydrogen. All the stars in the universe? Hydrogen.
Elemental hydrogen is what fuels the sun. It is a giant ball of hydrogen gas that is sufficiently dense to have enough gravity to hold together while undergoing continuous fusion reaction. The fact that the sun is roughly 93 million miles away and yet enough energy reaches the earth’s surface to heat the planet is astounding. 1383 Watts per square meter according to one estimate, which is what makes solar energy and solar hot water possible. All wind, all ocean currents and all plant growth which leads to all life on earth, is the result of sunlight falling on the earth. Pretty amazing.
Hydrogen is the first element in the periodic table. It has 3 times the specific energy of gasoline and a burn temperature about double gasoline. Since Hydrogen is also abundant on the Earth as water, covering 71% of it’s surface, it would seem like a perfect fuel source.
If you dig around you can find a number of attempts to use hydrogen as fuel. There are several vendors making hydrogen “add-on” kits for large trucks. Usually they generate a small flow of hydrogen from electrolysis of water which is added to diesel fuel or gasoline to increase its octane level. This increases the fuel efficiency and actually reduces emissions in most engines by increasing the burn temperature of the fuel.
Why isn’t hydrogen use more widespread?
Hydrogen is the lightest of elements. The pesky gas molecules like to react with oxygen to form water. If you can keep them pure, they like to float around. The energy required to compress hydrogen to liquid state is incredible, and liquid hydrogen must be maintained at 20 degrees above absolute zero at high pressure. Not easy to do and not easy to package into a vehicle.
Hydrogen fuel cells have been touted as the answer to our energy needs for quite some time. Why has there been so little acceptance?
Hydrogen as a fuel is not widely available. The most successful applications have been those where the hydrogen can easily be generated locally as needed. That has been limited to industrial fork lift users with large numbers of fork lifts, like in a large distribution center, and on municipal buses where the fuel can be generated in a bus barn at night.
The large fuel cell systems that are currently available use methane as fuel and strip the hydrogen from methane at very high temperatures. This would be OK if didn’t look a lot like combustion and didn’t result in a whole lot of CO2 being generated.
There are some promising options to consider. More next week.