Some countries / regions have mandated new commercial or domestic properties should include solar power.
California requires it on new builds.
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The EU is thinking about requiring it by 2027 on all buildings.
California requires it on new builds.
California Solar Mandate: What You Need To Know
New homes in California are required to have solar after January 1st, 2020. Here's what you need to know about the new law.
The EU is thinking about requiring it by 2027 on all buildings.