Ensuring that the lighting fittings you use have sockets that can only be used with lamps having an energy efficacy greater than 40 lumens per circuit-watt.
Sicrhau bod gan y ffitiadau golau a ddefnyddiwch socedi sy'n gallu defnyddio dim ond lampau y mae eu heffeithiolrwydd o ran ynni'n fwy na 40 lwmina fesul wat cylched.