tag:blogger.com,1999:blog-8543046762843691074.post5322746103048303819..comments2023-10-21T02:48:52.695-07:00Comments on JYA's various ideas: How do solar panels perform according to solar exposure..Jean-Yves Avenardhttp://www.blogger.com/profile/12581860475715822245noreply@blogger.comBlogger1125tag:blogger.com,1999:blog-8543046762843691074.post-88727375851630257172010-06-05T14:57:46.288-07:002010-06-05T14:57:46.288-07:00You assume that the trend line should go through t...You assume that the trend line should go through the origin. In fact what you are seeing is that below a certain level of irradience (ie. a very dull day) the system will produce very little or no power because the output voltage from the PV modules is too low for the inverter's MPPT algorithm, and the inverter itself consumes some power. All this means that there is no reason why your line should pass through the origin. <br /><br />In fact PV modules in general become slightly more efficient at lower temperatures but basically there's a lot less sun in winter than in summer. This means that for maximum annual energy capture the angle of the PV modules is set a little lower than would be the case if insolation in winter and summer were equally important -- if you want to optimise the system for winter then you increase the angle of the PV modules or put them on a tracking mount. Some people change the angle of their PV systems for summer and winter use, which typically gets them an extra 10% or so but really there are probably better and more effective things you could do in terms of upgrades to building airtightness and insulation.Unknownhttps://www.blogger.com/profile/17183927758292980912noreply@blogger.com