Solar panels aren't going to last a week in a public area. Look at almost any flat surface and what do you see today? Graffiti. If someone doen't paint it then someone else will destroy it.
And again enough with your political agenda. Oregon should be happy to welcome tourist eco friendly and fossil burning one alike. .The next time I will be traveling to Portland in is going to be on a huge fossil fuel guzzling / carbon spewing jet. As will the vast majority of tourists.