
Road map to clean energy using laser beam ignition of boron-hydrogen fusion - richardw
https://www.cambridge.org/core/journals/laser-and-particle-beams/article/road-map-to-clean-energy-using-laser-beam-ignition-of-boronhydrogen-fusion/8BE057DC1BC9E0A588FB3ABAA993078C
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kristianp
Reminds me of Bussard's Polywell, their website doesn't seem to have been
updated since 2014 though [1]. Bussard also wanted to do proton-boron fusion
due to the same advantages mentioned.

Edit: Apparently there has been progress, with a slideshow called "ready for
commercialisation" presented this August by Jaeyoung Park [2][3].

[1] [http://www.emc2fusion.org/](http://www.emc2fusion.org/)

[2] [http://www.talk-
polywell.org/bb/viewtopic.php?f=10&t=6072&st...](http://www.talk-
polywell.org/bb/viewtopic.php?f=10&t=6072&start=270)

[3]
[https://arpa-e.energy.gov/sites/default/files/5_PARK.pdf](https://arpa-e.energy.gov/sites/default/files/5_PARK.pdf)

~~~
dnautics
The polywell at least has some sensible suggestions on how to capture the
energy.

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JumpCrisscross
This is the process Tri-Alpha Energy [1] is working on.

[1]
[https://en.m.wikipedia.org/wiki/Tri_Alpha_Energy,_Inc](https://en.m.wikipedia.org/wiki/Tri_Alpha_Energy,_Inc).

~~~
dnautics
It's the same nuclear reaction, but I doubt tri alpha is doing laser ignition.

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ZenoArrow
Here's another project that is working towards using boron-hydrogen fuel for
nuclear fusion:

[https://lppfusion.com/](https://lppfusion.com/)

Brief description of how the device works:

[https://lppfusion.com/fusion-power/dpf-device/](https://lppfusion.com/fusion-
power/dpf-device/)

To be clear, Dense Plasma Focus is the type of fusion device, and LPP Fusion
is one of the teams researching them (there are others working with DPF
devices).

The following quote should help in understanding why it's an important
project:

[http://m.digitaljournal.com/tech-and-
science/technology/star...](http://m.digitaljournal.com/tech-and-
science/technology/startup-lpp-fusion-s-device-exploits-instabilities-to-fuse-
atoms/article/503354)

"“In the critical measure of how much energy out, we get per unit energy in,
we’re No. 2 among all the experiments in the world,” Lerner says. “And we’re
only one-third behind the JET [Joint European Torus] experiment in the United
Kingdom—which has almost a thousand times our resources. In terms of results
per unit dollar, we’re clearly No. 1, by a long way.”"

They're running a crowdfunding campaign, if you're interested in investing in
fusion energy:

[https://wefunder.com/lppfusion](https://wefunder.com/lppfusion)

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nicodds
The main advantage of this fusion reaction is that it is aneutronic, i.e. it
doesn't produce any neutrons, so it is relatively safe.

Petawatt class lasers are nowadays possible and several examples exists (Los
Alamos, Oxford central laser facility, ELI Prague, South Korea). The
technology used to compress photons energy in short length pulses is called
"Chirped Pulse Amplification". This opened the way to femtosecond laser
pulses.

------
sathackr
> 14 milligram HB11 can produce 300 kWh energy

That's an enormous amount of energy from a minuscule amount of mass. Using
their predictions, I could run my house for a year on less than 1 gram of
HB11.

How does this compare with the energy output of current-day fission reactors?

~~~
philipkglass
With mainstream present-day fission technology, it takes about 200 tonnes of
natural mined uranium to fuel a 1000 MWe reactor for a year:

[http://www.world-nuclear.org/information-library/nuclear-
fue...](http://www.world-nuclear.org/information-library/nuclear-fuel-
cycle/introduction/nuclear-fuel-cycle-overview.aspx)

The same 300 kWh would then require about

(300 / (1000 * 24 * 365 * 1000)) * (200000000) = 6.85 grams of natural
uranium.

Note that this is well below the theoretical energy density available from the
fission of uranium. The main loss is because the naturally fissile isotope of
uranium, U-235, is less than 1% of naturally occurring uranium. The much more
common U-238 can be used completely in a breeder reactor, but there are
currently only two operating breeder reactors in the world that generate
electricity:

[https://en.wikipedia.org/wiki/BN-600_reactor](https://en.wikipedia.org/wiki/BN-600_reactor)

[https://en.wikipedia.org/wiki/BN-800_reactor](https://en.wikipedia.org/wiki/BN-800_reactor)

------
jsjohnst
> 10 petawatts laser for one picosecond

> magnetic field plasma containment

> produces 300KWh

I’ll admit, while I’ve always been interested in lasers, I’m definitely below
amateur level with them, but these requirements:

1) seems like its multiple orders of magnitude higher power than anything I’ve
heard of in laser tech. Like 5-7 orders of magnitude. Is there research I’m
unaware of here?

2) let’s assume for a second that the laser could be made, wouldn’t it require
multiple orders of magnitude more power (as in 2-3 at least) to fire than what
this reaction produces?

3) have we been able to contain plasma (as in super high energy plasma, not
the stuff you see in novelty shops or older TV sets) for very long in a
magnetic field? I thought the record was in number of seconds, certainly not
long enough to be used for any continuous power production.

Edit: Guess I was wrong on #1/2, had forgotten about this research[0] I’d
read.

[0] [http://www.iflscience.com/technology/world-s-most-
powerful-l...](http://www.iflscience.com/technology/world-s-most-powerful-
laser-2000-trillion-watts-what-s-it/)

~~~
throwawayaway12
There are definitely petawatt class lasers currently (ex. the Texas petawatt).
I think most are of order 100 fs.

~~~
jsjohnst
Per the research I just did, 2PW has been done for one picosecond, 10PW is
being built. Apparently because of the very very short pulse, the energy
required is trivially small (as in less than a light bulb in your house for an
hour)

------
deepnotderp
Why not apply plasmonic nanoparticles for electromagnetic field enhancement
via nanofocusing?

(source:
[http://iopscience.iop.org/article/10.7567/JJAP.55.08RG01/pdf](http://iopscience.iop.org/article/10.7567/JJAP.55.08RG01/pdf))

I've seen this paper floating around for a while but not many attempts at
experimental validation.

~~~
amirhirsch
I’ve had an ongoing conversion with a few other people about using
electromagnetic metamaterials for field enhancement and focusing in a plasma
channel. We had previously worked on optical metamaterials for chemical
sensing, and the idea for plasma enhancement was for considering staging and
filtering methods for plasma wakefield accelerators in order to generate
enough GeV for free electron lasing. The same idea could be used for proton
acceleration for fusion. Possibly a concern is heat generated in the material
by an accelerated plasma may be incompatible with passive coloumb-mode
filtering. We had considered a target might be something like a disposable
cartridge similar to other laser fusion designs. A very clever result in
wakefield staging (out of the research labs) involves using a VHS tape for
sacrificial optical coupling. The 10PW 1ps laser described in the parent post
is not practical and would require similar staging methods.

------
tehabe
"14 milligram HB11 can produce 300 kWh energy" – I guess it means thermal
energy, how much of it can be used for electricity? What do I need for
producing this? How small can be such a power plant be or how big must it be
to be viable?

Of course this could be all answered in the paper but it is a physics paper
not a business or economics paper.

~~~
Retric
Their is a wide range of thermal efficiency but something ~30% to 64% is
possible. We can also use the heat directly in some applications making it
useful number on it's own.

Unfortunately making those pellets is fairly expensive an you only get 8$ or
less worth of energy from them. Which is why the economics of this idea is
simply terrible and the only value is for validation of H-bomb simulations.

~~~
DennisP
Since most of the energy output of boron fusion is in fast-moving charged
particles, you aren't necessarily restricted to a thermal cycle. Focus fusion,
for example, gets a pulse of alphas in a tight beam, which they can just aim
through a coil for electricity. Tri Alpha also has plans for direct
conversion, but I don't know how theirs works.

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exabrial
"...a few kiloteslas..."

This is a really cool paper and abstract. I had to giggle a bit at that
line... I think the MRI machine I had images of of my knee was something like
6T?

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rfrey
This asks for $35 to read the article, to save other non-academics the click.

~~~
cinquemb
[http://www.cambridge.org.https.sci-
hub.tw/core/journals/lase...](http://www.cambridge.org.https.sci-
hub.tw/core/journals/laser-and-particle-beams/article/road-map-to-clean-
energy-using-laser-beam-ignition-of-boronhydrogen-
fusion/8BE057DC1BC9E0A588FB3ABAA993078C)

------
qume
Dr. Emmett Brown: 10 petawatts! 10 petawatts. Great Scott!

McFly: Wait - what the hell is a petawatt?

Sorry couldn't resist.

------
Semiapies
And ten years from now, someone will submit something, maybe also from
Cambridge, saying we're really, _really_ close to a breakthrough allowing
clean fusion energy.

They've been saying _exactly this_ for longer than the 42 years I've been in
this planet.

~~~
fpoling
The problem with fusion was that until recently it was extremely expensive to
build experimental facilities with necessary parameters for meaningful
progress. Nobody was ready for that.

What happens recently is that due to technological improvement (powerful
superconductive magnets, better simulations and faster controls) it is now
possible to test things at regimes close to positive energy output on much
smaller scales. So these days one can do useful investigation with 1e7 in
funds, not 1e9. This is the reason for all various fusion startups.

Now, it does not mean that we are going to have fusion soon, but at least it
is now only 20 years from any moment, not 40.

~~~
Semiapies
The line has _always_ been that fusion is twenty years away. In 2017, in 2007,
in 1997, in 1987, and in 1977.

It will be the same line in 2027.

------
sandworm101
Whenever I read about "ignition" my mind goes strait to weapons research.
There is a blurred line between those looking wanting to use fusion for
purposes of generating power, and those seeking to further nuclear weapons.
'Ignition' generally draws a good line between the two. For instance, the
National Ignition Facility isn't doing reactor development. If I were the
author, I'd reconsider the title to emphasize that it's focus is the
generation of electrical power.

~~~
manigandham
The title already says "road map to clean energy" \- how much clearer does it
need to get?

Besides _ignition_ is a well understood scientific word and nuclear fusion
isn't useful for weapons.

~~~
FriedPickles
Fusion is used for boosting, boosting is needed for miniaturization. In the
absence of explosive testing I believe a facility like NIF is useful for
weapons.

~~~
sandworm101
Boosting is something that can be done in all sizes of weapons. It just means
adding some hydrogen into the primary fission device, as simple as filling the
otherwise hollow pit/core. When you read about "dial a yield" technology, that
is about adding or removing the boosting hydrogen from the primary. Vent it
off and you get a lower yield.

