Cost of Ownership in Hawaii: Model S + SolarCity

Cost of Ownership in Hawaii: Model S + SolarCity

We used to live 1000 ft from Tesla HQs at the Stanford Industrial Park. We moved to Honolulu from the Bay Area 16 months ago. Our first electricity bill was $488 month. HECO, the utility company charges 33 cents per kWh, and all the plants are diesel-fueled. We had SolarCity installed 41 PVs and the bill went to $17/month. I already saved $6,500 plus 2,500 kWh in the bank.

I then ordered a Tesla Model S which is expected to come in May. The excess electricity generated by PVs will be more than sufficient to keep the Model S charged without drawing on the grid. This means we do not need to line up for gas, and saved $80/week!

The following is our projected savings by 2032 (PVs are guaranteed for 20 years)

Electricity $189K

Model S $121K

NPV AT 5% Discount = $135K

Internal Rate of Return = 38%

I have a spreadsheet if anyone wants it. Please email me at

Joseph1ng | 3 avril 2013