Why don't we use H2 as our source of energy?

Question

I understand that current use of fossil fuel emits co2 as product, which causes global warming. I also learnt that hydrogen has potential to release a big amount of energy. What stopped us from using hydrogen?

Answer 1

It may be more appropriate to work on a cell that converts CO2 plus water into methane, or some sugar. We have a molecular process in the plant that can convert CO2 plus water into sugar and oxygen. Just add sunlight. The sugar is just a storage medium for solar energy. This strategy has some advantages and disadvantages. But at least stored sugar represents CO2 out of the atmosphere. We can stand to run the factory every day and just let the inventory build if we don't use it all.

Otherwise we can just harvest sea vegetation that is otherwise creating dead zones, dry and stack it for fuel in our currently coal burning electric plants.

Answer 2

Iceland is looking to become the Middle east of the Hydrogen economy. With the countrys' vast reserves of geothermal power, it is in a unique position to be able to produce liguid hydrogen much cheaper than almost anywhere else in the world. It is already running both hydrogen burning and hydrogen fuel cells in it's government fleet. With a poulation of just over 300k it is the perfect place to testbed a hydrogen society. It is expected that by 2020 Iceland will be exporting significant quantities of liquid hydrogen.

Answer 3

There's no abundant natural supply of hydrogen we can tap, except what's bound up in water.  

In order to get the hydrogen out of water, you have to break it's molecular bond to the oxygen it's tied up with in there.

That requires energy.  In fact, it requires exactly as much energy as you can get when you burn the hydrogen.  Because burning the hydrogen is exactly the same operation as seperating it from oxygen, in reverse.  

In practice, all mechanical operations being less than perfectly efficient, you can never get back as much energy from burning the hydrogen as what it took to get the hydrogen from the water.  

Hydrogen thereore is not practical as an energy source.  It is practical as a clean automotive fuel, however, as long as you have lots of clean energy available to split water to get it.  We could use nuclear energy to produce all the hydrogen we need for hundreds of years, for example.

As to why this isn't being done already, the conventional wisdom is that it's cheaper to burn oil.

However I do think the conventional wisdom is at least in part a biased product of the oil lobby.  

The cost of gasoline has gone up 300% in just the last ten years for example.  And I think all our military activities in the middle east for the past fifty years or so should be counted as part of the cost of our dependence on oil as well.  To say nothing of the damage we are doing to the enviornment, and the cost associated with that.

So yeah, while I wouldn't necessarily insist that hydrogen must be pursued as the exclusive alternative, I would say the remarkable lack of a national effort to find any alternative is largely because of the oil lobby, the politicians it owns, and a lazy, complacent public as well.

Answer 4

the hindenburg.

Answer 5

Where are we going to get it from?

Answer 6

First of all, I think you're referring to H, not H2. Oxygen occurs in gaseous state as O2, Hydrogen as H.

Why don't we use it? Because in order to isolate it from the other chemicals it's mixed with, we have to use a lot of power, in the first place. Then we have to use more power to compress it. Where do we get this power from to prepare the hydrogen? That is the question. Most power comes from burning coal or natural gas, from nuclear power stations, or from dams which destroy entire ecosystems.

It might *look* like hydrogen fuel cells are clean because they don't cause any direct pollution, but when you look at the amount of power it takes to isolate and compress hydrogen, and the pollution caused  by whatever power source we use for this purpose, it is not so clean.

The whole idea that hydrogen is the next clean energy source is bunk until we find a reliable, clean, safe way to isolate and compress the hydrogen. We don't have that yet.

Answer 7

The simple answer is that Hydrogen by itself is not an actual source of energy. The reason for that is that to make hydrogen you have to expend energy to extract it from either water or oil (Hydro-carbons - think hydrogen-carbons). The end result is that hydrogen isn't mined or refined as a primary source of energy, but instead can be used as an energy storage source. I.e. You can use coal or oil or nuclear (or renewable energy sources) as the power source to extract the hydrogen and then store the resulting hydrogen in a tank. Later you can use the hydrogen and extract the "stored" energy for many common use such as driving a car powered by hydrogen.

Hydrogen is not a new source of energy - it is only a way to store energy for later use.

Timothy D.

West Melbourne, FL