U.S. Department of Energy Energy Efficiency and Renewable Energy

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July 30, 2012

How do other communities use development regulations to protect solar access?


The most effective point in the development process to protect solar access is when a parcel is being subdivided into lots for sale. Some communities have development regulations that require developers to orient and design lots so that structures of a certain height at certain location on each lot will not block solar access to adjacent lots. In effect, each lot then has a permissible building envelope where a structure can be built while still allowing the adjacent lot to the north access to the solar resource.

There is no single default method for protecting solar access in areas that have already been developed. A number of development regulations include a process for obtaining solar access permits or recording solar easements, which establish a right to solar access for an existing or planned solar energy system on a specific lot.
Beyond enabling solar access permits for a specific solar energy system, some development regulations require new structures on existing lots to conform to “solar setbacks” in order to protect solar access more generally. These setbacks are determined by a formula that factors in the height of the structure, the angle of light when the sun is at its highest point on December 21 (i.e., the winter solstice), and the slope of the lot.

As an alternative, a few communities use the concept of a “solar fence” in their development regulations to protect solar access for existing lots. A solar fence is a hypothetical opaque fence of a specific height encircling a lot. New structures must not create more shade than would be created by this solar fence.
Examples from PAS EIP-30

  • Ashland (Oregon), City of. 2011. Municipal Code. Title 18, Land Use; Section 18.70, Solar Access.
  • Boulder (Colorado), City of. 2011. Boulder Revised Code. Title 9, Land Use Regulation; Chapter 9-9, Development Standards; Section 9-9-17, Solar Access. Fort Collins, Colo.: Colorado Code Publishing Company.
  • Clackamas (Oregon), County of. 2011. County Code. Title 12, Zoning and Development Ordinance; Section 1000, Development Standards; Part 1018, Solar Balance Point/Infill Ordinance, and Part 1019, Solar Access Permit Ordinance.
  • Fort Collins (Colorado), City of. 2011. Land Use Code. Article 2, Administation; Division 2.8, Modification of Standards; Section 2.8.2, Modification Review Procedures. Article 3, General Development Standards; Division 3.2, Site Planning and Design Standards; Section 3.2.3, Solar Access, Orientation, Shading. Article 5, Terms and Definitions; Division 5.1, Definitions. Fort Collins, Colo.: Colorado Code Publishing Company.
  • Laramie (Wyoming), City of. 2009. Code of Ordinances. Title 5, Business Taxes, Licenses and Regulations; Chapter 5.58, Solar Rights Permit System. Tallahassee, Fla.: Municipal Code Corporation.
  • Prairie du Sac (Wisconsin), Village of. 2008. Code of Ordinances. Title 10, Land Use Regulations; Chapter 8. Solar Access.
  • San Luis Obispo (California), City of. 2011. Municipal Code. Title 16, Subdivisions; Chapter 16.18, General Subdivision Design Standards; Section 16.18.170, Easements for Solar Access. Seattle, Wash.: Code Publishing Company, Inc.
  • Santa Barbara (California), City of. N.d. Solar Access Packet. Municipal Code Chapter 28.11, Protection and Enhancement of Solar Access.

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