Ohms law plays a big part in all this. Resistive losses are governed by the square of current multiplied by the resistance of the wire. As such running higher voltages minimises these losses. We use this all the time with our power transmission lines which generally run at 500kV AC if I recall correctly.
1. Safety is relative. 10-20mA is enough to kill a person. In AC voltage we measure it as root mean square, the actual peak to peak voltage is greater than Double that.
2. There are such things as solid state switching. Solid state relays and field effect transistors come to mind. This is also how we down convert DC power to lower voltages, very fast switching giving an average voltage that is the target (see buck converters).
3. DC power is everywhere and it is easy to do DC to DC conversion. Single chip solutions exist. Hell your car is entirely 12V (if ice powered, EV's are a different matter)
1. Safety is relative. 10-20mA is enough to kill a person. In AC voltage we measure it as root mean square, the actual peak to peak voltage is greater than Double that.
2. There are such things as solid state switching. Solid state relays and field effect transistors come to mind. This is also how we down convert DC power to lower voltages, very fast switching giving an average voltage that is the target (see buck converters).
3. DC power is everywhere and it is easy to do DC to DC conversion. Single chip solutions exist. Hell your car is entirely 12V (if ice powered, EV's are a different matter)
Hope that helps :)
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