First, I don't know of anyone who wants solar to be the only source of electricity. Most environmentalists are picturing some combination of solar, wind, hydro, geothermal, and possibly nuclear. Anyway, to power the US off solar alone would take about 262 square kilometers of solar panels:
https://inovateus.com/2017/08/03/many-square-miles-solar-panels-take-power-u-s-smaller-think/
To put that in context, New York is a little over 122,000 square kilometers. So, you'd be covering a little more than 2/10 of 1% of New York. The Northeast as a whole is about 420,000 square kilometers, so it would be a bit over six-one-hundredths of 1% of the Northeast.
A rational approach.