Each case study below tracks an actual Perth Synergy or Horizon customer through bill analysis, system sizing, installation, and the first 12 months of bills after switching to solar + battery. Numbers are real, names are anonymised, and the underlying spreadsheets are available on request.
Bill amounts shown are the Synergy / Horizon billing-period totals. ROI uses conservative tariff escalation (2% p.a.) and assumes the household stays on the same plan post-installation.
Key Issues:
Financial Outcome:
"The calculator showed us exactly what size system we needed. Three months in and our quarterly bill dropped from over $800 to around $220. The battery means we barely import power in the evening."
— The M. Family, Example scenario
Key Issues:
Financial Outcome:
"We didn't need a huge system. The assessment showed 5kW was the sweet spot for our daytime usage. With the STC rebate we only paid $3,000 out of pocket and it's saving us $1,200 a year."
— John & Margaret T., Example scenario
Key Issues:
Financial Outcome:
"Switching to the EV Add-On tariff alone saved us hundreds. Adding solar means we charge the car for free during the day. Combined savings on power and petrol are over $3,000 a year."
— David & Lisa L., Example scenario
Key Issues:
Financial Outcome:
"We couldn't justify a battery on our budget, but 6.6kW solar with the STC rebate was only $3,300. It's already saving us nearly $2,000 a year. Best investment we've made for the house."
— Emma & Chris P., Example scenario
Key Issues:
Financial Outcome:
"Running the pool pump during solar hours instead of overnight made the biggest difference. Combined with a 10kW system and Midday Saver tariff, our bills dropped from $950 to $225 a quarter."
— Michael R., Example scenario