EME 810
Solar Resource Assessment and Economics

9.2 Solar Rights and Solar Access


Reading Assignment

  1. S. Bronin (2009) "Solar Rights" Boston University Law Review. (only portions of the full paper are required reading)
    • Introduction (all)
    • Why Individual Solar Rights (all)
    • Governmental Allocations (read the Intro; scan the sections on Permits and Zoning)
    • Court Assignments of Rights (read the Intro)
    • Conclusion (all)
  2. DSIRE Solar Portal: Search by state, focusing on "Solar Access Laws". e.g., this Maryland Solar Easements and Rights Law.
  3. Wikipedia: "Solar Access"

One of the main limitations to deploying solar energy is just the simple ability to make use of the Sun's energy. Here, we focus on the right to access and use the Sun's energy, and the functional ability to access unobstructed solar energy within the solar envelope. Try to remember that many technologies and objects that are outside serve as SECSs: homes and solar panels, yes, but also clothes lines, patios, and trees.

The DSIRE solar portal describes both solar rights and solar access (easements), along with a map of US states having each or both. Note that PA still has neither solar access laws, nor solar rights laws. The Wikipedia description is also a general framework to think about access to solar energy in society.


Just think, in Germany, you have the right to be exposed to sunlight directly in any office scenario (no windowless cubicles permitted). In many states, you have the right to hang dry your clothes on a line outside. In ancient Rome, an individual had the right to access solar gains or be compensated for an obstruction of that resource. When we talk about policies for solar energy, one of the first is the basic ability to access that sunlight and then make use of it to do work!

The concept of solar rights is still emerging in the USA. I am going to recommend that you take about 10 minutes to review the current state of solar rights from the Solar America Board for Codes and Standards (the Solar ABCs; choose 1 page summary). The coverage is brief but useful when considering the scope of solar legal status in the USA.

Solar Rights

The phrase "solar rights" is often used in a general sense and a specific sense. In general, solar rights are the broad class of legal rights to access and make use of the light from the Sun. In the specific sense, solar rights are distinguished from "solar access" by the following description:

  • Solar Rights: the legal ability to install SECS on your property that is subject to land use restrictions. One of the classic SECS rights is the ability to dry your clothing outside on a clothes line. Perfect high utility SECS, but often blocked by local suburban covenants that would consider such displays as unwanted for the overall "appearance" of the neighborhood.

Here, solar rights describe the ability to make use of solar energy in your locale.

Solar Access

Solar access is the functional ability of a SECS within a locale to receive or "access" solar gains across property lines without shadowing or other obstruction occurring from buildings/trees/landmarks set in a nearby property. It also has to do with the enacted local policies to manage the commons of the solar resource system, and an individual's ability to be granted compensation if access is blocked in some way. Bronin has described solar access as being managed in three manners: as a solar easement, through covenants, and through lease agreements.

  • Solar Easements: the legal ability for a property owner to use sunlight across property boundaries. Easements allow a designated landowner to hold some rights with respect to the property of another landowner. Such an easement will have been voluntarily bargained for and agreed upon. In such a case, one client will receive access to a solar corridor/envelope, while another landowner will receive some compensation to offset the burden from losing the access. [Bronin, 2009]
  • Covenants: binding terms for current owners and those that follow later. A covenant can function well for newer subdivisions of homes, but they are more challenging to create for nonresidential regions or well-established residential areas. Of course, covenants have also been used to inhibit the use of SECS like clothes lines, foliage/tree types and density, and even visible displays of PV/SHW systems.
  • Lessor-lessee arrangements: agreement that ties a solar right to the temporary term of tenancy. Solar leases will typically involve airspace (solar envelope or solar skyspace). Airspace has a common law role as real property, and is distinct from ground/mineral estates. A client owning property has the potential to sever the parcel of ground from the airspace, and then lease just the airspace. As such this type of lease allows the solar client to make use of or “occupy” the airspace without obstruction.

We have already discussed the role of minimizing shading in SECSs that intentionally collect and convert solar gains (rather than shading devices that attempt to control solar gains). Solar access has to do with access to the solar resource within the locale over many hours of the day, and across the months of the year. Recall that we already developed some skill to assess the solar access at a site through the sun path diagrams in Lesson 2. Hey, we just tied together something that was a lot of work earlier with an advanced topic in Lesson 8! Great!

Solar Envelope

The solar envelope is an extension of solar access, conceived for urban scenarios with a cluster of buildings and obstructions. Professor Emeritus Ralph Knowles of the Dept. of Architecture, the University of Southern California, conceived and developed an extensive exploration of the solar envelope as a concept for policy development and planning. You are welcome to read about Dr. Knowles' solar envelope concept in complement to our assigned reading.

Supplemental Reading 

R. Knowles, "The Solar Envelope: Its Meaning for Energy and Buildings"Energy and Builduings, 35, 15-25 (2003). 

Self-check questions:

1. What is the term describing a citizen's right to install SECS on their own property?

Click for answer.

ANSWER: Solar rights.

2. What is the term describing a client's ability to make use of light for home heating purposes or other SECS, accessed beyond the client's property boundaries?

Click for answer.

ANSWER: Solar Access, also termed solar easements.

3. Why should we advocate for solar rights (writ broadly) for a building as a SECS?

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ANSWER: Solar access is extremely valuable to the individuals who have it. For homes, three economic measures are influenced: resale price of the structure (premium for naturally lit space); increased productivity of occupants (work better with natural light than artificial light); and decreased operating costs of heating, cooling, and lighting systems. [Bronin]

4. Why should we advocate for solar rights (writ broadly) for outdoor areas?

Click for answer.

ANSWER: Light in outdoor areas can also have financial consequences: clients can grow local garden produce, develop crops for sale, or use sunlight instead of electricity to dry laundry (avoided fuel costs). [Bronin]