Daily Archives: November 1, 2013

Is is time to packetise electricity?

It is a couple of decades now since electricity cables were first demonstrated as potential telecomms networks, and some applications of that are commercially available now. You can even use special adapters that plug into a mains socket to communicate with devices in other sockets, though wireless LANs make that much less significant now.

However, an obvious derivative of that has also been known for decades but is still missing. That idea is to packetise the electricity itself. The electric current would still be constant, but each bit would have a communications packet written on it. That would allow electricity to be sold peer to peer, to be assigned to specific purposes, and rationed in time of shortage. It is closely related to smart metering, just a different way of doing something similar.

Here’s an example of how this may be used in practice: A power supplier could issue packets of electricity labelled according to their permitted use. Most of the time, all packets would be labelled open use and could be used for any purpose. When load is high and supply is limited, some packets would be marked restricted use. They could be used for lighting or a hair dryer, but not to power a freezer or electric heater, or battery chargers. Enough open packets would be issued to provide minimal power to these secondary uses, so that your ice cream doesn’t melt and your gran doesn’t freeze to death, but they would provide an excellent way of smart targeting for power rationing. In fact, grans might be allowed to use power for heating when some other homes aren’t, if they are known to have alternative supply for example.

What is meant by ‘each bit’ needs some thought though. To offer useful service potential, energy needs to be broken into quite small pieces. An electrical unit is far too large. I think a Joule is about right – 1 Watt for 1 second but I haven’t really though about it much. Millijoules would be feasible technically, but I don’t think they add much in terms of potential.

Energy from different suppliers could be labelled differently, but share the same wires, just like telecomms traffic. You could choose to run your house on just renewable energy, or just nuclear, or be bloody minded and insist that it has to come from a coal station just to annoy your green neighbour.

There has to be an incentive to use compliant appliances, and they would cost a little more for the embedded intelligence to understand the packets. The main incentive would be price reduction for the energy used, or perhaps event-specific rewards for allowing a local ban during peak times. They could even be offered in advance.

Peer to peer sale of electricity from a small wind turbine or from solar panels on a roof would work too. Instead of selling electricity back onto the grid at a poor price and some neighbour buying it back from the grid at a high price, peer to peer allows direct sales at mutual advantageous pricing, cutting out the middle-man and adding competition.

So there could be a market and it could work. I guess it’s up to the industry to decide whether this is a sensible alternative to smart meters.

Will plasma be the new glass?

Now and again, everyone gets a chance to show the true depths of their ignorance, and I suspect this is my chance, but you know what? I don’t really care. I have some good ideas as well as dumb ones, and sometimes it is too hard to know which is which. I freely admit that my physics is very rusty. However….

Plasma is essentially a highly ionised gas; lots of ions and free electrons. It conducts electricity so is ideally suited to magnetic confinement. You make a current in it, and use magnetic field interaction with that current to hold it in place.It can also hold a decent charge overall, positive or negative. That means it interacts electrostatically as well as magnetically. Electromagnetics is all one big happy field anyway.

A strong magnetic field can be made that encompasses the plasma magnetically without it needing to be surrounded by a solid object. Let’s do a thought experiment.

Start off with a sealed ball and make a small hole in it, put an electric coil around the hole, send some current through it, and make a field around that hole to stop plasma escaping. Ditto the opposite side of the ball, so now you have a tube with plasma in it, albeit a fat tube with narrow ends. Gradually make the hole diameters bigger and bigger, and the tube shorter and less curvy. Eventually you will have more or less a fat disk of plasma. The relative dimensions of the disk will depend on the intensity and control of the magnetic field, the ionisation of the plasma and any currents you make in it.

With some good physics and engineering, adequate sensing and a decent control system, I reckon it should be possible to make reasonable sized disks of plasma. So, make two of them. Put the two disks reasonable close and face to face. Arrange them so that the electric currents in the plasmas run in different directions too. If they are both similarly charged overall they will repel electrostatically and their internal magnetic fields will also interact, but the managed applied magnetic fields could stop them deforming too much. Add more disks, and we have plasma plywood. Let’s call it plasma-ply for lack of a better word.

I can’t calculate how thin this plasma-ply could be made. I suspect that with future materials such as graphene and room temperature superconductors, future remote sensing and advanced computer control systems, they could be pretty damned good. If you try to deform one of these disks, it would resist, because the magnetic and electrical interactions would create force to keep it in place. We have another name for that. We call it a force field and we see them in every space opera. If the surrounding coils and other stuff is just a think ring, as you’d expect, you’d have a round window. Maybe a smallish window, but you could use a lot of the coils to make a big window in a honeycomb structure.

So we can bin the word plasma-ply and start using the words we already have. We will have force fields and plasma windows. Plasma will be the new glass, and an important 21st century building material.