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Winter Solstice Sun and Shadow Paths—Micro version

This video illustrates the sun’s path (and the shadows it casts) on the winter solstice—the day with the longest shadows of the year—for a site at 32˚ N latitude. Awareness of such shadow paths enables you to maintain winter sun access.

The perspective is from ground level.
See here for the macro version of this video for a perspective from the sky, enabling you to see the changing location of the sun throughout the day.

This video also illustrates how you can use an awareness of these paths, along with winter-solstice shadow ratios for your latitude [see the chart here] to determine the length and angle of shadows cast by various objects, to maintain winter sun access where needed for passive heating, lighting, and on-site solar-power production.
For example, you can use the shadow ratios for your latitude to figure out the length of shadow cast by a tree (once it reaches its mature size), so the tree can be placed where it will maintain, rather than reduce or eliminate, your ideal winter solar potential. 
Note that in the video the tree is planted within a water- and leaf drop-harvesting basin.

See chapter 4 and appendix 7 of the book Rainwater Harvesting for Drylands and Beyond, Volume 1, 3rd Edition, by Brad Lancaster available at deep discount direct from the author for more on this and other simple, effective, and dynamic integrated design tools.

Active SystemsPassive SystemsSun and Shade Harvesting
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