Plug Power, Inc. (NASDAQ:PLUG) shares are climbing on Wednesday, continuing the stock's recent upward trend. The stock has gained more than 15% in the past five trading sessions and more than 20% in the past 30 days. This is potentially due to strong delivery numbers reported by electric vehicle makers, which could be a positive catalyst for clean energy names including Plug Power. PLUG has considerable short interest with 19.39% of available shares currently being sold short and has garnered attention from retail investors on social media.