When I was 17 I made a science project of making fuel using cow farts. Actually it was inspired by this - Cow Backpacks Trap Methane Gas . Fun fact : 550-kg cow produces between 800 to 1,000 liters of emissions, including methane, each day.
You get out less than what is put in.
If you really want to collect some high efficiency energy, wrap the sun completely in a sphere of inward facing solar panels. But then, we waste a lot of energy having to heat and light up the planet. You never really win here.
*goes and hugs a tree*
I know that electricity can be produced economically, but is that going to be the case here. Probably not.
Fossil fuels will be burnt to produce the very electricity that will generate this fuel.
Do not get me wrong, I am all for alternative energy, but this just isn't the miracle that everyone is looking for.
I will be very happy to be proven wrong.
For the US , the answer is , has been and for the next 5-10 years will be natural gas.
If Humans have a 100 year life span, you would have to grow 5 x 10^7 = 50 million Humans per year in order to maintain a steady population of 5 x 10^9 = 5 billion Humans.
If it takes 10 years to grow a Human until the Brain is Mature, the total number of immature Humans being grown at any particular time would be 500 million.
If each Human has a 10 meter square area, or 100 square meters, the total Farm area would be 10^2 x 5 x 10^8 = 5 x 10^10 square meters, the area of a square about 2 x 10^5 meters on a side.
The Farm would fit in a square about 200 kilometers on a side.
How do you put that in your car?
I was mainly talking about automotive fuel.
You can use the energy to make dimethyl ether, ammonia, etc. Sorenson names a few in the video.
You can also feasibly get this reactor technology down to the size of a backpack.
Or, we enhance battery tech in the next 5 years to the point where we have instant recharge and better storage capacity and then combine that with a far greater capacity to generate and use energy and you will have all of the utility with a smaller carbon footprint than ever before.