Fusion power is something of a pipedream/golden bullet/panacea for our energy problem woes. If it can ever be made to work, then it will be much better than anything else in existence. Almost no radiation, none at all when the reactor isn’t running, and the vessel would be radioactive for about 100 years, unlike fission plants. No fuel based pollution, unlike fossil fuels. Runs 24/7 no matter the weather, unlike solar and wind power. Doesn’t take up space needed for other things, unlike biofuels.
This sounds awesome. So what’s the catch? Well, they are really hard to build, get energy out of, and,of course, really expensive.
One of the major hurdles with fusion power is that has to be overcome is that until just last year, we always had to put more energy into the reactor than we could get out of the reactor.
To make fusion work, we have to create conditions nearly equivalent to the inside of the sun. Inside the reactor vessel, we have to heat a mixture of hydrogen isotopes to about 150 million degrees Celsius. Then we have to contain the plasma and keep this superhot mixture both under pressure and from actually touching anything (like the reactor walls or air). These are three major power drains. Create a maintain a vacuum. Create and maintain a magnetic field. Create and maintain 150 million degrees Celsius.
The current estimate by the ITER project is that it will take 50 Megawatts of power to get the fusion reactor running. If the system doesn’t generate more electrical energy than that, it’s a waste of time.
August 26th of last year, that important milestone was reached by the US National Ignition Facility. But it was a completely different design than what I just described. The NIF used 192 lasers that all fired so as to hit a small pellet of deuterium (a hydrogen isotope) simultaneously (and I mean exactly at the same time) with over 350 Terawatts of peak in five millionths of a second. For that one moment in time, more energy was produced than went into the lasers.
The ITER project plans to use 50 Megawatts of power to be able to continually produce 500 Megawatts of power.
Seven member countries are involved in the ITER project. They are China, the European Union, India, Japan, Korea, Russia, and the United States. After the ITER fusion plant is up and running (around 14 years from now), the consortium will build DEMO, which is intended to be an operational powerplant that will actually provide electricity. If that project goes well, then we could begin to see operational fusion power plants maybe by 2035 (when I’m into my 60s).
Like many things in the world. There are several ways to do something. Some ways are very difficult, but can provide enormous benefits. Some ways are easy, but have major drawbacks. It’s time to start doing things the hard way, so the easy way doesn’t damage our planet any more.
Some more resources on fusion projects:
ITER – a consortium of seven countries building a working fusion powerplant in Southern France.
NIF – the US National Ignition Facility
EFDA – The European Fusion Development Agreement
