If we look at the trailing 12 months of EPS, the stock has an EPS of 5.35 and a P/E ratio of around 12.99.
Now, the last 3 quarters of the year were quite good and if we add the next quarter estimates, (see below) the Trailing Twelve Months EPS will be around 6.5 (even if you don't agree with my estimates).
At a P/E of 13, this means a stock at around $87, and if the P/E also comes close to a realistic value of 15 given the growth potential of First Solar, we could go all the way to $100.
Something to think about, when the next earnings are coming out.