ON the topic of hydrogen - It is extremely inefficient, we can only extract it by using using oil, at the moment it uses as much energy to extract as you would get out of it. At the mo it's only a feesable fuel source at the moon and mars.
While on nuclear energy - Sorry if I am going to go on a rant here but - It is absolutely ridiculous that we are not using more nuclear energy, windmills, solar panels etc. are terribly inefficient. My country last year spent over 1 billion (A large sum for Ireland) building windmills. We will never get back this energy, the amount of concrete and metal used in the building of these damages the environment much more then it will ever save it too.
You may say, "oh what about nuclear waste and meltdowns etc." Yes you'd be right, but if the entire world used nuclear energy the amount of waste created per person would be the size of a golfball.
But that isn't the best bit- We are NOT using the right source for nuclear energy - Instead of using depleted uranium and plutonium we can use Thorium.
Thorium is three times more abundant then Uranium, DOESN't create nuclear waste, in fact it eats it, it is much easier to extract and damages the environment less, a Thorium reactor CANNOT have a dangerous melt down meltdown, it doesn't emit as dangerous particles and then, it doesn't have to be refined as much to use.
We even had a working prototype in the 60's and now India are making a load of reactors, they plan to have 30% of their energy made by Thorium in 2050.
You may ask why we don't use this miracle fuel source? - Simple, in the 60's they wanted nuclear weapons, you can't make nuclear weapons with Thorium. And since they have just kept the existing extracting and refining plants.
On fusion, they have only made somewhat successful cold fusion so far, when we break it it'll be an amazing fuel source.
I'm 16 BTW.