A. Any covenant, restriction or condition contained in any deed, contract, security agreement or other instrument affecting the transfer or sale of, or any interest in, real property which effectively prohibits the installation or use of a solar energy device as defined in section 44-1761 is void and unenforceable.
B. A deed, contract, security agreement or other instrument affecting the transfer or sale of, or any interest in, real property entered into before April 17, 1980 shall not be subject to the provisions of this section.