Rather then turn it upside down so the hail would hit it at 90 Deg. if there was a way to detect the direction the hail was traveling you could turn the panel to a 20 to 30 Deg. angle to the hail travel direction. At 90 deg it has to take the full impact of the hail. at am angle all it does is deflect the hail. Another thing to consider is if the hail bounces back up and hits the face of the panel. Bob Robert Rolf wrote: >This assumes that the backside is more impact resistant than the >front. Every PVP I've seen has as little backing as possible because >of weight issues. >But if you beefed up the back with something strong enough to resist >4" hail, and spaced it from the panel so that impacts weren't coupled >into the fragile cells, then this is a 'doh!' idea. > >Robert > >Robert Ammerman wrote: > > > >>For the hail: >> >>Don't turn the array vertical, turn it upside down! >> >>Bob Ammerman >>RAm Systems >> >> >>----- Original Message ----- >>From: "Howard Winter" >>To: "Microcontroller discussion list - Public." >>Sent: Thursday, August 24, 2006 7:54 AM >>Subject: Re: [EE] Solar Array Tracking >> >> >> >> >> >>>Bob, >>> >>>On Tue, 22 Aug 2006 02:03:59 -0700, Bob Axtell wrote: >>> >>> >>> >>> >>>>I too am beginning to think calculating will work better than anything, >>>>especially if time corrections >>>>can be made by RS232 serial once a day or so. >>>> >>>> >>>I think it depends on the climate. Where James lives it's clear skies >>>almost every day, so time/date tracking would work fine most of the time. >>> >>>But here in Blighty it's cloudy as often as it's clear, so moving the >>>array when the whole sky is giving the same insolation is wasting energy. >>>In this >>>case you could probably optimise using a time-steered sensor which tracks >>>the Sun, and a matching one on the array. Then you can calculate how >>>much extra energy will be collected by moving the array by comparing >>>readings from the two sensors, and only moving if it's worth it. It's >>>very >>>unlikely that an area of sky away from the Sun will produce more energy >>>than pointing at the Sun, it's a question of whether the extra is worth >>>the >>>energy to move the array from where it is, rather than where it should be >>>for max. energy. >>> >>>Cheers, >>> >>> >>>Howard Winter >>>St.Albans, England >>> >>> >>>-- >>>http://www.piclist.com PIC/SX FAQ & list archive >>>View/change your membership options at >>>http://mailman.mit.edu/mailman/listinfo/piclist >>> >>> >> >> -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist