Just found this thread. Doc's post is well back but it has errors which need addressing.
Hadn't seen that article on 41% efficiency in solar power. However, it would have the effect of cutting my sizes in half for the solar-power discussion.
Although higher efficiency technologies do exist they invariably use exotic materials and are not cost effective compared to the existing silicon cells. One particularly ridiculous technology uses Cadmium Telluride. Aside from the danger of the material when it burns (as would happen occasional in a house fire) there is not enough Tellurium on the planet to make it practical.
Just remember, we can never get more than 6 watts per square meter ANYWHERE on Earth from solar at 100% efficiency
Incorrect. Insolation at the equator is about 1000 Watts per square metre about eqaul proportions of light and heat.
Here's another gotcha. You know those lovely all-electric cars with the lithium ion batteries? They work great until the batteries finally degrade to the point of not holding a charge for longer than an hour or two. When you go to dispose of those batteries, they qualify as TOXIC WASTE!
Ever heard of recycling? I believe Toyota includes this as part of the deal when you buy one of their hybrid or electric models.
Remember, resistance in a circuit is computed by intrinsic resistance times linear distance and I think there is an added factor due to the inverse frequency relationship of the implied RC and LC frequencies of any circuit. The bigger the circuit, the bigger the R and C, and I think the L factor goes up too. This is one of the reasons why Nikolas Tesla's generators were not efficient. Tesla's system was direct current, whereas Edison used alternating current. Tesla's long-haul lines suffered EMF losses due to LC and RC issues.
For the non-electrical engineers among you, circuits have inherent frequencies based on the Resistance-Capacitance - RC - or Inductance-Capacitance - LC - characteristics of the circuit. When you hear an electronics techie talking about "ringing" in a circuit, this comes from the LC and RC properties of said circuit forming the electronic equivalent of an acoustic resonator box on a guitar or violin.
A somewhat confused and inaccurate explanation.
Firstly Tesla used AC while Edison used DC. A typo I guess.
The losses in power lines are very little to do with incuctance and capacitance of the transmission circuit itself. AC does loose power through electromagnetic radiation by inducing currents in nearby conductors but this has zilch to do with resonance. Losses are quite low in air but undersea transmission is always done in DC becuse salt water is conductive.
Inductance in long line DC transmission would be a bigger problem. The current would simply continue as an arc across any break in the conductor. High voltage DC voltage is a circuit fault protection nightmare. DC arcs are very difficult to extinguish. This is why DC lines are always incredibly well protected and voltages are very low compared to AC. You won't ever see them as overhead lines. The thought of a 330 KV DC transmission line would be terrifying indeed.
In very long AC power lines where the length reaches a significant fraction of the wavelength (5000 to 6000 km) it can cause devestating resonances when loads change suddenly. A great deal of attention is paid to this factor in long distance power line design.
The big weakness of DC in Edison's day was the impossibility of transforming voltages to reduce the current and hence the transmission losses. The only way then might have been with motor generator set but a high voltage mechanical commutator is impractical. Tesla invented transformers which we still use today with voltages in the hundreds of thousands.
Load inductance causes the current to lag behind the voltage wave and increase the current relative to the power, lowering the Power Factor and increasing losses resistive losses. However large consumers generally correct their power factor because they are charged on current rather than power. This was not practical in Tesla's day because capacitors were not advanced enough. It is no longer an issue.
Moreover the power factor is fully corrected for most of the generators at the power station by devoting a specially configured generator to supply the lagging current of inductive loads. The other generators supply in phase current very, very efficiently.
As I mentioned earlier, just remember that the price you pay for going solar is the amount of square footage you must dedicate to capturing the rays.
Perhaps not in some places but more than enough space is available on the roof of most homes in Australia to generate their entire electrical needs using existing technology.