A 12V battery-powered home emergency light using a low-energy mains lamp

This circuit will operate a mains low-energy light bulb of up to 24W rating from a 12V d.c. supply. As well as being useful for home emergency lighting, it could be made part of a solar or windcharging system for use in areas where a mains supply does not exist

A 60Ah lead-acid battery (“leisure battery”) makes an excellent power source and will operate a 24W low-energy bulb for some 24 hours before the need to recharge. For lighter loads, a smaller sealed lead-acid unit is recommended.

The circuit presented here is a form of voltage converter. It thus accepts a d.c. input at one voltage and changes it into a d.c. output at a different voltage.