Hi I have similar issue before with my tnb bill suddenly increase from 200 to 300 even consumption wise is much ot less the same throughout the year. Later found that solar water heater on roof top water leak out with boiling water..after turn off the water tap to minimize water wasting leaking from the roof top, out of suddenly house electricity power trip. Later after an hour checking by electrician ,we detected old wiring have expose to water and it cause power trip. Maybe you can ask the wiring techician check on the water pump wiring or water heater wiring. See if that help....

After I found the main issue, I switch off the electricity power supply to solar water heater...from there on tnb bill reduce back to normal