CINCNORTH N

Suppose You have a high voltage power generator that produces say 10 mA at 10.000.000 volts (10 MV). The power is, obviously, U*I = 100 kW. The technical problem is to devise an efficient way to convert this power into usable low-voltage electrical power source, say 100 V at high current. How can it be done? Remember that standard semiconductors cannot operate at such high voltages.

Serious answers only, please.

Large scale space travel can be expected in the future, as Earth's resources become exhausted and the human population rises. Every spaceship leaving or coming down to Earth changes its momentum. Can large scale space travel change the Earth's momentum so much as to affect its orbit and create inhospitable environment? Can this be calculated? Bear in mind that even minute changes in momentum can affect the orbit, and that even minute changes in orbit can severely impact the climate.

In the same context, can using tidal power (i.e. converting potential energy in the gravity field between Earth and Moon and Sun into other forms) significantly affect the same parameters (orbit, climate, relative positions)?