Taken from comment on WUWT:
The primary fuels we have were provided by Mother Nature, and she did the dirty work for us millions and billions of years ago. The energy provided in hydrocarbon fuels are the result of photosynthesis from solar energy and for nuclear fuels from supernovae.
To “design new fuels” from whole cloth will be an environmental disaster many times anything realized from the production of our current primary fuels.
It took 100’s of millions of years and millions of cubic kilometers of ocean water, and photosynthesis to deposit 100’s to 1000’s of feet of organic rich sediments in basins across the globe. These organic rich sediments where then buried by solar energy. Yes, solar energy evaporated the water from the seas and lifted it 10,000 plus feet into the mountains and the rains formed river that carried the sediments to the oceans and deeply burial the organic layers. Then, energy from supernovae in the form of radioactive decay of uranium, thorium and potassium heating the interior of the Earth pyrolyzes the deeply buried organic matter to form liquid and gaseous hydrocarbons, and coal.
So, the scale of production (e.g. land area, water volumes, farm produced organic matter, etc.) needed to make these newly design fuels that would replace any significant fraction of the ~500 quadrillion Btu’s that is consumed yearly, will make an oil refinery look like a nature preserve.