( From Science Daily, though I have seen more about it in news...

( From Science Daily, though I have seen more about it in news sites. ) 17Oct14
“Perhaps the biggest roadblock to adopting fusion energy is that the economics haven't pencilled out. Fusion power designs aren't cheap enough to outperform systems that use fossil fuels such as coal and natural gas.
University of Washington engineers hope to change that. They have designed a concept for a fusion reactor that, when scaled up to the size of a large electrical power plant, would rival costs for a new coal-fired plant with similar electrical output.
The UW researchers factored the cost of building a fusion reactor power plant using their design and compared that with building a coal power plant.”
“Lockheed says its version will fit on the back of a truck.”
My commentary:
You would be familiar with Moore’s law, whereby the number of components on a computer chip doubles every 2 years, and pretty-well all technology follows this pattern, growing at exponential rates.
The same will happen with nuclear fusion plants. Presently, it might look like a 10 year time frame, but next year it could happen, and the electricity sub-stations will soon be the generating hub for local area consumers.
My interest in this from an investing perspective is that this new power source will have a devastating effect on several major investment classes.
Power utilities will be the first to avoid, and quite obviously the price of fossil fuels will flop, never to recover. Not that the fossil fuels will be useless, they will just be in greatly less demand. I certainly would not invest in gas or coal long-term.
Aluminium will no longer be required for high voltage transmission lines because transmission lines will become redundant. The huge amounts of steel and zinc and whatever else used in the construction of pylons will be much less valuable too. I really don’t think that iron ore will recover much above the minimum cost of production of the largest and most efficient producers.
Copper consumption may not be much affected; indeed there may be an increase in demand as these power plants spread throughout the third world. Gold and copper are often co-produced, so I would still invest there at the right price, which is now or fairly soon.
Vast quantities of cheap power produced where it is needed will render hydropower dams back to fishponds.
Electric trains will carry their own power plants.
Absolutely forget about “renewable energy”, that will be museum pieces, as will be most solar cells, mains electricity will be just too cheap and reliable to compete with. Wind turbines will be stopped from rotating because of the adverse environmental impact they have, and they will become white elephants of technology, like cathode ray tubes.
Aircraft will be able to stay aloft for years; some kinds of satellites will become redundant, and much less frequently employed will be the launch equipment. Aircraft can land when hardware needs upgrading or repair, whereas satellites are often permanently lost, contributing to the problem of space junk.
Ships will be early adopters of the new technology, and that will devastate many related businesses.
Think of the effect that the electronic revolution had on Kodak and the photography business in general. Bill Gates advised Warren Buffet not to continue his planned purchase of Kodak, and he was right to do so. Many large and important industries will very quickly decline, and the profits for investors will come from different areas. I can think of geriatric services, high-tech medicine, education, military hardware and software.
Some metals and natural products will continue to increase in value; these things need to be evaluated on a case-by-case basis. I would venture that titanium will continue in demand, as will lithium.
This is a subject which must occupy the upper-most thoughts of active investors for decades yet, as the world goes through a change as great as that wrought by the advent of the internal combustion motor.