Plug Power (NASDAQ:PLUG) is at the forefront of the hydrogen-power movement of the 2020s. However, it’s not prudent to over-invest in Plug Power. Position sizing is crucial with Plug Power stock, as there are risks involved and share-price volatility should be expected. Don’t get me wrong. I’m rooting for Plug Power to succeed and eventually post a quarterly profit, though that goal remains elusive.Still, I like the way Plug Power continually innovates and advances fuel-cell technology. Someday, the company ...