a 12V 50W lamp and a 230V 50W lamp both consume 50W all other things being equal.
However the 12V lamp requires a transformer which will consume a little more.
The thing is though that 12V lamps tend to turn more of the W into light and less into heat than the 230V ones so to get the same light output you need less of them or less wattage .
As a rule of thumb 230V lamps are perceived as about 30% less bright.
I said "perceived" rather than "they are" because I think the eye/brain relationship gives a logrithmic effect rather like the ear/brain relationship.
Hope that helps.
Hopefully , one day soon, the LED arrays will give decent light outputs rather than just decorative effects
However the 12V lamp requires a transformer which will consume a little more.
The thing is though that 12V lamps tend to turn more of the W into light and less into heat than the 230V ones so to get the same light output you need less of them or less wattage .
As a rule of thumb 230V lamps are perceived as about 30% less bright.
I said "perceived" rather than "they are" because I think the eye/brain relationship gives a logrithmic effect rather like the ear/brain relationship.
Hope that helps.
Hopefully , one day soon, the LED arrays will give decent light outputs rather than just decorative effects
