A 12 V source is enough to glow a bulb specified for that source. If we use that source in our homes then you need to make the cables 20 times bigger in section.
To produce same brightness from bulb, 12V bulb require 19 times more current than 230V bulb. That means the 12V power supply wire size must 19 times thicker than the wire to run 230V. Example: to run 1200W stove with 12V power, it require 100A and the wire size becomes as thick as a finger. Copper is an expensive metal and a finger thick wire is heavy,expensive and difficult to install. Do you want to use 12V in your home ?
To get the same brightness out of a 12 Volt bulb as a 230 Volt bulb would require almost 20 times the current.
To carry that kind of current, you would need much thicker wires, and you would likely still suffer resistive losses.
You can deliver more power over thinner wires at a higher voltage. That's the efficient solution. The trade off is, of course, that higher voltages are more dangerous than lower voltages.
12 volts is plenty to drive the lights and appliances in your home. You do not need the 230V. You can use many batteries to run everything. Just as you have said.. but wait, You will need to recharge the batteries which you can do with a car engine just fine. oh wait you need gasoline to run the engine. You can do this with a 1 000 gallon gas tank on the front lawn. That will do just fine but wait you will need a fire department permit for the tank. This will only cost several hundred pounds a year. but wait what about the noise. The neighbors will complain. Sell the house and move to the country. This will only cost a few Killo-pounds, then you will be all set.
Good idea, thanks.
Power = Voltage x Current
By increasing the Voltage we can reduce the current by increasing the resistance to maintain the
same Power
Isn't it a waste of resources to step it up?
