How Do You Protect Solar Systems From Financial Loss Due to Shading From New Developments or Trees and Shrubs on Adjacent Properties? Posted on Jun 20, 2017

This guest blog by Angela Lipanovich, President of Estriatus Law, PC, is also posted on Estriatus Law’s Legal Review (June 20, 2017).

Access to sunlight is often called the most difficult legal issue connected with solar energy use.  The ancient precedent of “ancient lights” holding that a person has a natural right to receive the light that passes through their window has be unanimously repudiated in the U.S.  No common law legal right to unobstructed light from adjoining land exists.1  Thus, solar system owners must rely on i) a limited availability, if any, of general zoning rules and solar access permits; iii) the design and location of their solar systems to account for potential shading from adjacent properties, iv) limited governmental statutory protections to solar access for their systems, and v) in the absence of any of the former, private agreements with neighbors to secure the availability of sunlight to reach their solar energy systems. 

General zoning rules and solar access permits are policy tools a limited number of states and local governments across the country have developed to limit shading from neighboring properties.  In some cities, such as Boulder, Colorado, zoning districts are grouped into different solar access areas that provide a limited amount of solar access protection through the concept of a “solar fence” on the property line,2 and in other cities, such as Santa Cruz, California, the general zoning requires that buildings must be oriented and located to “preserve solar access of adjacent properties.”3  Other policies grant specific solar access protections through providing solar access permits to use the airspace over their neighbor’s property. Although policy tools of these types succeed in providing some protection for solar access, such tools are only of limited help given the highly variable and limited amount of protection they provide which can also be difficult and expensive to enforce. 

In many cases, solar easements are the most practical solution to the problem of the right to solar access when no governmental protections suffice.  For instance, California has limited statutory protections that provide solar system owners some guarantees to access to sunlight.  In California Gov. Code § 65850.5, local governments are provided with the authority to require certain subdivisions, by ordinance, to create solar easements but only to subdivisions for which a tentative map is necessary and subject to other restrictions.  The California Solar Shade Control Act (“Act”) provides that a tree or shrub cannot cast a shadow which covers more than 10 percent of a solar system’s absorption area at any one time between the hours of 10 a.m. and 2 p.m. if the tree or shrub is planted after the installation of the solar collector.  The Act also exempts trees and shrubs subject to a local ordinance and the replacement of trees and shrubs that had been growing prior to the installation.  Under the Act, if a neighbor does not remove or alter an offending tree or shrub after reasonable notice, then a penalty of $1,000 per day is imposed until the violation is removed.  Since the Act excludes existing vegetation solar owners must account for expected growth of vegetation that might shade their system.  Also, no law prevents shading of solar energy systems from new or modified structures on adjacent property.  Thus, in California, aside from these two statutory protections, solar system owners must rely on well thought out system designs and locations or obtain a solar easement from one or more neighbors to guarantee solar access for their systems. 

Over thirty states have enacted solar easement statutes.  In 1978, California was one of the first states to enact legislation to guide the establishment of solar easements.  California’s solar easement statute is found in Cal. Civ. Code §§ 801 and 801.5.  This statute allows neighboring property owners to sign solar easements that prevent a property owner from using their property in a manner that would prevent sunlight from reaching a solar energy system located on an adjacent property.  Pursuant to the statute, a solar easement can only be used for accessing sunlight to create thermal or electric energy using a solar energy system.

Under California law, all solar easements must be in writing and include, at a minimum, all of the following:

  1. A description of the dimensions of the easement expressed in measurable terms, such as vertical or horizontal angles measured in degrees, or the hours of the day on specified dates during which direct sunlight to a specified surface of a solar collector, device, or structural design feature may not be obstructed, or a combination of these descriptions.
  2. The restrictions placed upon vegetation, structures, and other objects that would impair or obstruct the passage of sunlight through the easement.
  3. The terms or conditions, if any, under which the easement may be revised or terminated.

See Cal. Civ. Code § 801.5.  Solar easements should also be recorded in the office of the recorder where the easement is granted or serious problems could result at a later date when new owners make any structural or landscape changes that prevent sunlight from reaching their neighbors property.

As solar energy becomes more ubiquitous, the problem of shading from structures on adjacent properties is sure to become more prevalent.  The reputations of solar in general and the companies that sell solar in particular could be impaired if consumers do not receive the financial and environmental benefits they expected or were promised due to shading from structures on adjacent properties not being considered at the outset of the proposal process.  Solar easements are an effective tool when considering the overall solar energy development strategy. 


  1. Fountainbleau Hotel Corp. v. Forty-Five Twenty-Five, Inc., 114 So. 2d 357, 359 (Fla. Dist. Ct. App. 1959)
  2. Boulder Revised Code: Title 9, Land Use Regulation; Chapter 9, Development Standards; Section 17, Solar Access.
  3. Santa Cruz 24.08: Land Use Permits and Findings; Section 43 (5).