As for cleaning it, it will work no matter how you point it, so put it vertical, aim it at the neighbors you like the least (or you could aim it at an angle in

As for cleaning it, it will work no matter how you point it, so put it vertical, aim it at the neighbors you like the least (or you could aim it at an angle into the sky as well). But you can't reduce the cost and danger of that monster significantly : * a quartz : ? * SiC : not exactly cheap in large panels, but ok * MgF2 : this substance is NOT welcome in my house (you can't safely touch it, and if it gets vaporized or granulized in a fire or because someone puts a drill to this thing, people will start dying), also : expensive. * TiO2 : very very expensive * Ag : silver. Surprisingly cheap. This thing has the same problem as nuclear power. Solid state, yes. Easy, powerful and (probably) lasts hundreds of years. But it can turn a small misstep into a neighborhood extinction (exaggerated, but then so is nuclear power's dangers)