The problem had always been one of efficiency: getting electrical power into the home while wasting as little of it as possible in the transfer. At the far extreme of the home itself, the simplest way had always been to throw a wire at the property, charged with an electrical current; no-one had really found an easier way of getting electricity to the final usage points. There were inevitable losses involved in transfer over wires, but that wasn't where the major efficiency gains were to be made.
The way it had been before was this: a patchwork of locally-administered generation plants, perhaps a few serving each city, mostly using methods which hadn't changed for hundreds of years. By far the most common had been the heating of water in order to spin magnets, which had compound problems: use of a dirty fuel to heat the water, resulting in massive pollution, and the inherent inefficiency of the process. People in the power business once talked about 30% as if it was a good figure.
Of course, major problems arose if a city came close to running out of power. Because each of these local generation plants was fixed, and it was hugely expensive to build another one, the residents often faced such concepts as the rolling blackout instead of having a reliable supply. Such an idea sounded like a ridiculous way to run a city.
It took the invention of two seemingly seperate technologies to change the status quo. The first was practicable nuclear fusion: the creation of a little star in order to feed off its output. The Earth as a whole seemed to get along just fine with fusion, lapping up the rays of the Sun; if the planet could do it, the human race could adapt the technique.
The final race to build a viable fusion plant had been between China and the United States, but the breakthrough came from neither quarter, but from a research laboratory in France. The lab had been approached by both sides, but refused to give the plant away in exclusivity; instead, the technology was released for the world to use.
There was just one problem: size. The fusion plant was incredibly large, and no city could viably set aside such a huge chunk of land to house what was essentially a giant metal sphere. It took another invention before that issue could be alleviated.
It was called the HCD by the research team who came up with it: the High-power Collimating Diffractor. Its original target was satellite TV, where large amounts of power were wasted by spreading a signal over spaces which would never have a reception dish. Instead, the HCD split the signal into focussed beams, which could then be directed every which way, towards a specific dish on the ground or to another HCD for more refined splitting.
The real breakthrough hadn't come until Rihanna Johnson had her Eureka moment: generating radio waves from a fusion plant, and splitting with a HCD. The generation of radio from fusion was a simple enough matter, and had been done before; the plant gave out incredibly intense light, which could be shifted down to radio using technologies 50 years old. That wasn't the main thrust of the idea, though; the word which made the world sit up and take notice. That word was: space.
If fusion plants were so massively large that there was no way to house them on land, they could be hoisted into space instead. From there, they could generate high-powered microwaves, split into millions of fractions by a network of HCDs in orbit around the Earth, which could then beam the power down to reception dishes in every town and village.
It was a radical idea, not least because it meant abolishing the local generation infrastructure that had been painstakingly put into place over hundreds of years. The item which eventually forced the issue was, of course, cost: the price of all fossil fuels was steadily rising, and at some point in the late 21st century, all the accountants had worked out at the same time that it would in fact be cheaper to set up the fusion network than to keep the old plants running.
That was the gist of the history lesson Ryan gave in his unofficial capacity as tour guide for Fusion Pacific. He was a microwave researcher by profession, but most people up here had to take multiple jobs, simply due to a lack of personnel; it fell to him to show the tourists around.
Hawaii was the tethering point for Fusion Pacific: a huge cable, stronger than diamond, attached the land mass of the Earth to the giant ball of the power plant thousands of miles above. The space elevator had already been in construction when the fusion network had been floated as an idea; since the original plan had been to simply leave the end of the cable free in space, the fusion plant was deemed to add only a small percentage to the total mass of the system were it coupled to the endpoint.
There were two other stations in the fusion network: America, attached somewhere in the Amazon, and Eurasia which was fixed to an island off the coast of India. These had been the original three elevators, and three fusion plants was more than enough for all the world's needs.
The tour normally consisted of a trip around the plant, starting at Earth side and working around to star-side while Ryan explained the history of the network. While working back to Earth-side, the tourists could examine output graphs from the fusion plant if they so desired, or fiddle with a sample light-frequency HCD that Ryan had put together. Instead of splitting microwaves, it split red light into hundreds of thin beams, programatically directed at will; it made for interesting lighting, if nothing else.