General situation and occupation
The chalet in question is situated in the canton of Grisons in eastern Switzerland at an altitude of 1500 m. It has a good southerly outlook. It can be reached by car in the summer, but preferably in a 4 x 4 as the road leading to it is not tarred. In winter, snowfall makes access more difficult: the owners get there with the help of cross-country skis and skimobiles. A family of four owns the house and occupies it regularly but only at weekends. Sometimes in summer they stay longer. The nearest mains electricity is 5 km away as the crow flies, but in any case they do not want it since they prefer the wildness of the site as it is.
The chalet is not far from the well-known resort of Davos, on which we will base our meteorological data. Its altitude is similar (1590 m), and this is important because the solar radiation conditions are much more favourable than in the valley (see Section 2.2.3).