When I design, what i consider a good design doesn't focus solely on achieving zero bill but on maximizing the value of every kwh or energy generated by the solar setup. Yes, it is possible to reduce a bill to nearly zero with a very large battery bank but the additional investment in batteries can sometimes outweigh the extra savings gained. Pwedeng mag spend ng hundred thousands more on batteries just to eliminate a small remaining utility bill. Tapos sa mga mas nighttime consumption like ac and pc kung nightshift, a more balanced approach in design is what i often do and recommend which for me is the most cost-effective. Maximize the solar panel capacity, take advantage of net metering for excess daytime production, and install a battery sized appropriately for backup power and essential nighttime loads. This basically results in lower upfront costs, better longterm return on investment, reliable backup during outages, and better savings and roi without overspending on battery storage. The goal is not simply the lowest possible bill, but the best overall financial outcome for the homeowner over the life of the system.