An experiment to test whether nuclear fusion can be controlled to generate power
nytimes.com
nytimes.com
Au contraire, my friend.
Unlimited cheap energy would bring on, in time, the next type of anthropogenic warming: the temperature of the planet being raised, not by a greenhouse effect, but by the raw power output of all those fusion reactors. Even if a good fraction of their thermal output is transformed into electricity, the electricity always finishes as decay heat, with very few exceptions.
The solution for that is to move the Earth farther away from the sun, which reduces solar input. Or injection of coolants such as sulphates in the atmosphere. Even with zero solar input, there's still an upper limit on how much decay heat we can release in the atmosphere without boiling ourselves.
Unlimited cheap energy on any plant would enable us to implement environmental controls, using that energy, so we could build habitats in hostile atmospheres.
With a working small scale fusion reactor we could colonise the entire solar system, the raw materials are all out there but energy is always one of the main issues.
I remember reading back in the 80's a plan for extracting metals, creating metal foam that would float and then dropping them into the ocean (some would be lost to rentry heat but it was a tiny percentage) where a drone ship would sail out and tow them in.
I would love to see something like that in my lifetime.
Not that Wikipedia is the best source, but...
World energy consumption is about 12 terawatts [1], whereas the Earth receives 172,000 terawatts in the upper atmosphere. [2]
The difference is 4 orders of magnitude. i.e. The Earth receives in one day the same power as produced by humans in 10-15 years.
I think we're safe.
> The solution for that is to move the Earth farther away from the sun
That's firmly in the realm of science fiction. The power required to move the earth would be so enormous that it could power human technology for billions of years.
i.e. it would be energetically more efficient to use that power to fix the current problem, instead of doing something ridiculous like "move the Earth".
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As you say, the sun provides approximately 172,000 terawatts to the Earth, due to a solar irradiance of 1360 W/m^2 over the planet's cross sectional area of 1.27x10^11 m^2. While this is the correct value for the amount of energy received at the upper atmosphere, only some of it is actually absorbed by the Earth. Currently, approximately 30% of this energy is reflected back to space.
Anthropogenic radiative forcing was estimated by the IPCC in 2011 [1] to contribute approximately 2.29 W/m^2. This is the difference in solar energy absorption caused by human activities (such as releasing CO2). Multiplied by the area of the Earth, this is 290 terawatts of energy, which is many times greater than world energy consumption.
Also note that this figure is rapidly increasing - compare to 1.25 in 1980 and 0.57 in 1950 in that report, or 1.6 in the 2007 report [2].
[1]: http://www.ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_SPM_..., see page 12 [2]: http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-spm..., see page 4
Well, it doesn't need to equal the irradiance of the sun to be a big effect. 1% of the sun is still a hell of a lot of extra warming.
At an annual growth rate of 2%, that 12 TW becomes 1% of the sun in 250 years. Not all that long when solutions are 50+ years out. If you're a fan of keeping capitalism going, we're going to need faster growth than that.
We should research multiple avenues of energy independence (including fusion, and including how to increase conservation/efficiency of use) so that we can make real progress now and not hang our hat on a single magic solution.
If you know a little about fusion, it's very exciting and seems very real and very close. If you know a lot about fusion, it's exciting, but you realize that the odds of practical fusion power plants in our lifetimes are extremely low. The problem is that to get someone from one state of knowledge to the other requires their active participation, and most people see that as "pissing on their enthusiasm".
What did you make of the German (mainly) Stellarator[1]?
The ideal would be a total understanding of just how and where to "squeeze" the plasma with magnetic fields, so that the least possible input of energy is required and the plasma would essentially stabilize itself. The problem is that the ability to model that on a computer is only just coming along, and the W7-X is a big step forward in uniting those new models with a practical experiment.
Does it solve issues of breeding Tritium, diverting plasma, resisting atomic sputtering? No, but it does hopefully move forward the understanding of the underlying plasma physics.
This is a nice video explaining fusion power: https://www.youtube.com/watch?v=mZsaaturR6E
The interesting thing to me is the need for Helium-3, which we'll need to harvest from the moon.
Second issue: There are cheaper ways to produce no greenhouse gases than fusion energy, today. Wind, Solar, Nuclear, Geothermal, Wave, Hydro are all mostly CO2 free, just like Fusion. However, these technologies compete in the (very distorted) energy markets, have some environmental impact, social impact, and there is too low a cost to simply poisoning our air quality with cheap coal. Our grid designs are outdated, the way we regulate our utilities & their incentives also don't align.
Third issue: Fusion is well understood, plasma physics, the structure of magnetic fields etc. is the real issue, as other commenters have outlined. There was a mistake in our understanding of how even our microwave oven's fields are contained via the tiny Faraday Cage around them. Even Feynman was wrong about it: https://sinews.siam.org/Details-Page/surprises-of-the-farada...
> Q3. Somebody must design microwave oven doors based on laboratory measurements. Where are these people?
They're (1) deep inside large corporations like GE, LG, Sharp, and others - they have non-disclosure agreements, keycard locks on the doors to neighboring departments, and strict firewalls on their network connections. They don't publish, which is probably a foreign concept to this Oxford professor.
And (2) they are cannot afford to be this curious, they are time-constrained and budget-driven, which is also fundamentally alien to this professor's tenure-based worldview. They have to pass CE/FCC emissions regulations, and if a trial of a larger grid spacing or lower gauge says the device fails, that's the conclusion of the matter - put in the stuff that worked before. They certainly don't have a year to devote to understanding the fundamentals of Faraday cages.
Fossil Fuels (incl. Coal & Oil) receive a bigger comparative subsidy than clear energy. Ref: https://www.bloomberg.com/news/articles/2014-11-12/fossil-fu...
You'll note that the article simply says:
>Fossil fuels are reaping $550 billion a year in subsidies and holding back investment in cleaner forms of energy, the International Energy Agency said.
and then nothing else about what those subsidies actually are.
It would make sense that sectors that generate the vast majority of energy would receive the most of those capital investment subsidies - they are actually receiving a far small amount comparatively.
Do you think any scientific research ought to be funded?
Maybe the search of fusion is the cause we have never encountered aliens.
This wasn't an outrageous assumption given how cheap fuel costs were. But it turned out that running real-world nuclear plants had enough other costs to not be much, if any, improvement over other sources of power.
Fusion fuel is really cheap, but that doesn't necessarily mean that fusion power will be.
[0] http://www.lockheedmartin.com/us/products/compact-fusion.htm...
I guess it's another example of how it's easier to destroy than to create.
For comparison, controlled fission was performed before the explodey kind, and the first fission electricity was produced only three years after the first fission bomb.
We already know that fusion works just fine for the sun - this is not the argument that I would use. And it's my opinion that we've already proven fusion can't be cost effective (producing excess energy) with the current reactor designs. I'd rather this money went towards moon-shots that were proposing alternate ways of achieving fusion.