Ideas page updated

I updat­ed my ideas page. I added an entry about using com­pressed air to auto­mat­i­cal­ly remove snow (or sim­i­lar) from solar cells, and an entry about maybe using heat from ther­mal solar cells to gen­er­ate elec­tric­i­ty at home. I also updat­ed the entry for non-optimal weath­er opti­mized solar cells with a link to a com­pa­ny which seems to do some­thing sim­i­lar (using a lens) to reduce the cost of solar pan­els. To cool down the pho­to­volta­ic cells, the com­pa­ny is using a heat exchang­er to make a com­bined photovoltaic/thermal pan­el. Unfor­tu­nate­ly they are mak­ing an unfair com­par­i­son of the com­bined out­put of this pan­el (the ther­mal pow­er out­put is much high­er than the elec­tric pow­er out­put) with a nor­mal pho­to­volta­ic cell. A nor­mal house­hold needs more elec­tric­i­ty than heat so you do not want to use a lot of such pan­els, but depend­ing on the fea­si­bil­i­ty of my idea about using heat to pro­duce elec­tric­i­ty, such a pan­el could be interesting.