The Sentinel Solar Roof Pump was developed by a licensed roofing contractor and a team of solar engineers to be a cost-effective solution to standing water on flat roofs. It’s the first ponding pump on the market with patent pending “Smart-Chip” technology and cold weather protection. The unit is incased in spun aluminum with DuPont’s reflective powder coated surface and comes in three different models.  There is even a unit with a remote solar panel for areas that receive limited sun light!  Because of its patent pending design and technology it can pump for over three weeks with no sun what so ever!  It is an alternative to expensive re-pitching and re-decking or installing a new in-roof drain.  
For more info please visit https://www.solarroofpumps.com.