 The most practical orientation in the Tropics nearest the equator is north-facing toward the aphelion (or perhaps northeast) to moderate the temperature extremes.Just "outside" the Tropics, the most practical way to avoid afternoon heat excess may be an east-facing house or, if near a west coast, exposure of the east end and the west end, with the two "long" sides embedded in the earth.Depending on the region and site selected for earth-sheltered construction, the benefits and objectives of the earth shelter construction vary.