The future of residential building electrical installations

AJJewsbury:

When the house built in the 1930’s two electricity meters were installed, one for lighting and one for sockets. Electricity used for lighting was charged at a lot higher rate than for the sockets, because the cost of supplying electricity just for lighting, particularly on a summers evening, without daytime usage to justify running coal fired steam powered generators 24/7 is ridiculous.

I was told something slightly different for the reason for having two separate meters for power and lighting. In those days the local "corporation" (local council these days) usually ran both the gas works and the local electricity generator - and they did not wish the market for town gas to greatly disrupted by this new fangled electricity, nor electricity to be out-priced by gas. A gradual transfer of some of the market from electricity to gas would suit them nicely (and protect their existing investments). The trouble was that kWh costs for electricity were naturally higher than for gas, but electric lighting was far more efficient than lighting by gas (even using the old filament lamps we now regard as hopelessly inefficient) - so left to its own devices everyone would use electricity for lighting and gas for everything else, so the market for electricity would never fully develop. So the solution was a higher kWh price for "lighting" electricity (putting it on a par with gas lighting) and use the extra income to subsidise "power" electricity - so encouraging homes and industry to try out things with electric motors as well as heating. (Possibly also using the domestic market to subsidise industrial supplies too).


Of course that left a legacy of separate "lighting" and "power" circuits that we still have mention of in the regs today, not to mention different plug/sockets intended for power and lighting (which we've almost got rid of).

AJJewsbury:

When the house built in the 1930’s two electricity meters were installed, one for lighting and one for sockets. Electricity used for lighting was charged at a lot higher rate than for the sockets, because the cost of supplying electricity just for lighting, particularly on a summers evening, without daytime usage to justify running coal fired steam powered generators 24/7 is ridiculous.

I was told something slightly different for the reason for having two separate meters for power and lighting. In those days the local "corporation" (local council these days) usually ran both the gas works and the local electricity generator - and they did not wish the market for town gas to greatly disrupted by this new fangled electricity, nor electricity to be out-priced by gas. A gradual transfer of some of the market from electricity to gas would suit them nicely (and protect their existing investments). The trouble was that kWh costs for electricity were naturally higher than for gas, but electric lighting was far more efficient than lighting by gas (even using the old filament lamps we now regard as hopelessly inefficient) - so left to its own devices everyone would use electricity for lighting and gas for everything else, so the market for electricity would never fully develop. So the solution was a higher kWh price for "lighting" electricity (putting it on a par with gas lighting) and use the extra income to subsidise "power" electricity - so encouraging homes and industry to try out things with electric motors as well as heating. (Possibly also using the domestic market to subsidise industrial supplies too).


Of course that left a legacy of separate "lighting" and "power" circuits that we still have mention of in the regs today, not to mention different plug/sockets intended for power and lighting (which we've almost got rid of).