Your math skills are terrible. A Tesla model S has a 60kWh pack. A 15,000 watt system will full charge it in 4 hours if dedicated just to it. 15,000 watts of panels is well under 4500 sqft of roof space. An acre is 43560 square feet ten times larger. I could change 3 Tesla per day off my panels on my roof. Or run my dual HVAC at 68 degrees and still have 100kWh left over to charge two Tesla with. 60kWh takes a model S 330 miles. No one drives 300+ miles per day. The NHTSA has years of data that shows the vast majority of Americans drive less than 40 miles per day or less 80% by the data. 40 miles of charge is 10kWh in city mode driving. So my panels would meet the daily needs of ten Americans in model S Teslas no where near an acres worth of panels.
Here are 500 watt panels, for 15 cents per watt. A single panel in ten hours of day light would make 5 kWh two of them would charge a Tesla for that 40 miles per day. Ten of them would be a 5,000 watt system and 30 would be a 15kw system look at the dimensions of the individual panel.
Dimension 1956x1310x45mm
https://m.alibaba.com/product/62313907859/product.html
Do you drive at night or do you drive in the daytime? How much daylight do you have left when you return from your trip? Cuz you ain’t got nothing to charge that battery overnight.