How Compact Might Nuclear Fusion Reactors Become?

[DemonDragonJ]

Nuclear reactors are usually very large, but engineers have been working to design and build reactors that are smaller and easier to transport. For example, Lockheed Martin is currently working on a compact fusion reactor (CFR) that would be sufficiently small to transport on the bed of an 18-wheeled truck.

I find myself wondering if it would be possible to make nuclear fusion reactors even smaller, so that they could be fit inside of a building and power it. Technology is constantly improving, and devices that once were large and bulky are now small and sleek; therefore, I imagine that the same could happen with nuclear reactors, as well. I do not believe that nuclear reactors could ever become as small as portable gasoline-powered generators, but they could become as small as a common household furnace or water heater, which would make them able to fit inside an ordinary house.

Unlike fission reactors, fusion reactors are extremely safe (although it should be mentioned that fission reactors are also very safe, with incidents such as the Chernobyl incident or the Fukushima incident being the exception rather than the norm), since they have no possibility of melting down and do not produce harmful radioactive waste, so they would not be problematic being mass produced and owned by ordinary citizens.

What does everyone else say about this? How compact might nuclear fusion reactors become?

[x88x]

I cannot comment on the technologies involved, as honestly I really do not know them well. As such, I cannot speculate about how small they might get.

What I will say though, is that if they can achieve even "just" what they are stating on their site[1] (that is to say, a mobile, 100MW power plant in the size of a shipping container), and they can get even close to being cost-competitive with traditional power...there is an enormous market that they did not even consider in their video.

Datacenters.

According to some estimates in 2013[2], ~10% of world power usage went to IT infrastructure, and a big chunk of that is going to be datacenters. According to some more recent numbers from 2014[3], over the course of 2013, in the US alone, datacenters consumed approximately 91TWh.

My employer is in the business of building datacenters...lots of datacenters (lets just leave it at that...they're a bit touchy). Do you know what is one of the biggest roadblocks in building more of them faster? It's not the construction, it's not building and shipping the servers. It's power. The northern Virginia area is a hotbed of datacenter activity (for a lot of companies, not just my employer), and the demand is growing faster than the power companies can keep up. Imagine going to your supermarket and saying that you are having a kid and you need to get some baby food (or whatever you feed kids these days, I don't know). Sure, they say, we can get that for you! In just 5 years! ...but you have this kid coming in 9 months...you need that baby food. So what do you do? Well, you move somewhere else where you can get baby food.

..ok, that analogy got a little thin..

The point I was trying to make is that if you could go up to a major internet infrastructure company (or power company for that matter) and tell them that you can give them a shipping container that will generate 100MW for 20 years at an average cost of something even remotely approaching that of fossil fuel power...you wouldn't be able to build them fast enough.

[1] http://www.lockheedmartin.com/us/products/compact-fusion.html
[2] http://www.theregister.co.uk/2013/08/16/it_electricity_use_worse_than_you_thought/
[3] http://www.computerworld.com/article/2598562/data-center/data-centers-are-the-new-polluters.html

[Konrad]

Many people are researching fusion energy. Have been for half a century. Self-sustaining controlled fusion does not yet exist - although people always promise its just around the corner, one or two decades at most.

Dirty old nuclear fission has been around for just as long as the initiative to develop clean fusion. Its not magical, it cant rally be reduced much in size. Most of th bulk is intentional, thick lead panels and hardened concrete slabs and reinforced redundancies galore. The computer-controlled components can b reduced in size, sure, but only insofar as they can continue to provide maximum reliability. Things like concrete and water cannot b reduced without diminishing their shielding and cooling capacities.

The critical components might all be cleverly transportable in a single truck or plane. But thats not at all the same as a nuclear-powered truck or plane engine.