The US Government is absolutely fucking over its people with this because if solar panels are cheap, the installation cost makes its money back quicker, and people are simply leaving money on the table rather than waiting 15+ years for the investment to pay itself back.
The timing of the click captcha loading is randomized and it probably is looking for human-ish cursor movement? (Like you’re probably moving your hand in imperceptibly small ways that are difficult to replicate). Clicking before it loads and doing it repeatedly probably triggers detection.