Brain-storming is where you list any idea that comes to mind, no matter how wild or insane it appears.
Here are a few alternative power ideas that we came up with, that now do not appear to be quite that far off:
1. Store lightning. Two problems, you’d have to control the lightning strike and then have somewhere to store it.
EEstor, a Texas company, is building capacitors that are claimed to have nearly twice the energy density of Lithium-Ion batteries. They could drive a car for 300miles on a 5 minute charge. The EEStor’s only disadvantage is that today’s household wiring is unable to supply the needed current. I bet a bolt of lightening just might do the job.
2. Use solar power to create a chemical fuel similar to gasoline, rather than electricity.
This isn’t quite the same, but interesting none the less. Ecogeek.org has this article, “Could Chemical Solar Power beat Photovoltaics?“. Professor Chaurasia of the University of Birmingham, UK, is developing a process in which propanol is dehydrogenated, the hydrogen then generates electricity using a Proton Exchange Membrane fuel cell. The byproducts then recombine and begin the process again. I don’t know if this is as efficient as photovoltaics, but it might be another way to generate electricity.
3. Windpower. Most of the home-built wind turbines use permanent magnet DC generators, because they are cheap and easy to acquire. This is not the best way to generate electricity, especially as the current increases.
This company, Swift Wind Turbines, has a 1.5kW, 240 VAC, wind turbine that uses parts made locally. I’m very interested in this, except that it connects to the power grid, which indicates that it is most likely and asynchronous induction type, which can’t supply power unless the grid has power.
It occurred to me that you could use a wind turbine to drive both a permanent magnet DC generator and a moving field coil AC generator (Alternator). The current from the DC generator would only power the field coil of the AC generator, so the DC generator wouldn’t have to supply that much current and wouldn’t have to be that big . The AC generator would supply the usable current and could be direct wired (no sparks, no arcs). This arrangement should allow a low wind speed startup, with increased output power as RPM increased, because the power from the DC generator would increase, increasing the power in the field. The increased field would increase the output power. Also, as the field power increases, so would the back torque from the AC generator, slowing the rotor speed. Essentially, the RPM would be self regulating, while the power increases.
The Danish Wind Industry has a fantastic website related to wind generation, windpower.org. They should know, they produce a higher percentage of their power from wind than any other nation. Currently, 20%.
It will be interesting to see how these turn in a few years.