Geometry of Solar Envelopes

With the utilization of alternative energy resources in North America have come various mechanisms for protecting access to sunlight. The mathematical aspects of the problem have not been thoroughly treated in the literature. A solar envelope, over a parcel of land, defines the three-dimensional figure within which objects may be placed without obstructing sunlight to adjoiners during a specific time interval on all days of the year. A mathematical development of the geometry of solar envelopes is presented. A computational example and an analysis of the effects of errors inherent in some assumptions are included. Such treatments are necessary as legal descriptions of solar easements are being prepared and subdivision design constraints include provision of solar access to each lot.