Hi All,
Originally during my colour selection appointment, my power connection was marked as single phase power connection and opted to upgrade with surge protection. The upgrade item included was - "Provide single phase, complete house overvoltage protection (surge protection) installed in the main single phase switch board - $278.00 "
But now when I received the Tender document, the builder has updated the power connection from single phase to three phase as well as increase in cost for surge protection - total of $2453.00.
Please see the individual split below :
Provide three phase power connection meter box and surface mounted three phase switch board located in the garage, in lieu of standard single phase power connection and single phase board located in the meter box - $1487.00
Provide additional run of three phase underground from the electrical supply pit located on the front right hand side of the block to the meter box located on the side elevation of Master Suite - $162.00
Provide three phase, complete house over voltage protection (surge protection) installed in the main three phase switch board - $804.00
I am seeking your help with two main questions.
1. For what kind of load someone would require 3 phase power?
Mine is a single storey 29 SQ house with gas cooktop, electric oven, regular downlights, cooling/heating of max 5KW rated power input at the peak (with E.E.R./C.O.P. of 3+ it will provide 15KW of heating / Cooling capacity), then refrigerator, air fryer, vacuum cleaner, washing machine, condenser dryer that sort of regular white goods. Will get 5KW Solar installed. No plans for pools and stuffs. Alfresco has gas supply for BBQ. I am not sure whether I will really require 3 phase power for the current use. May be future proofing of electric car charging, but won’t that work with Single phase power? If I have 3 phase power, I guess as per the rule I should have the 3 phase inverter. In that case my solar power generation would be split in to 3 phases and I may not able to ensure that my air conditioner would receive all the available power from solar. Won’t that create a situation where the phase line used by air conditioner would have to draw extra power from power grid (high cost of 0.3 cents / unit) whereas the other 2 idle phases would feed ( only 0.1 cents / Unit credit for feed in) in the surplus unused solar energy to the Grid. Even if I use 3 phase air conditioner, I am unable to equate solar vs usage requirements. Aren’t these complications because of 3 phase power. Please correct me if I am wrong here.
2. Do you think what my builder quoted for 3 phase power supply and the surge protection looks alright? Is there anything that could be done post the handover cheaper than the rates from the builder (like the entire thing or even just the surge protection) ?
Your quick help will be highly appreciated as I will have to decide whether to go with a) three phase power connection and b) three phase surge protection Monday end of Day.
Thanks,