(a) For purposes of this section, the following words shall have the following meanings, unless the context clearly requires otherwise:—

''Building'', a building or multiple buildings on a parcel, or any grouping of buildings designated by the department as an appropriate reporting unit for the purposes of this section.

''Energy'', electricity, natural gas, steam, hot or chilled water, heating oil, propane or other products designated by the department that are used for heating, cooling, lighting, industrial and manufacturing processes, water heating, cooking, clothes drying or other purposes.

''Gross floor area'', the total floor area contained within a building measured to the external face of the external walls.

''Large building'', a building with at least 20,000 square feet of gross floor area; provided, however, that the department may establish by regulation a lower threshold for a building to be considered a large building under this section.

''Owner'', the owner of record of a building or a designated agent thereof including, but not limited to, an association or organization of unit owners responsible for management of a condominium, the board of directors of a cooperative apartment corporation or the net lessee of a building subject to a net lease with a term of not less than 30 years, inclusive of all renewal options.

(c) Annually, not later than June 30, each electric, gas and steam distribution company shall report to the department the total amounts of electricity, natural gas and steam used during the previous calendar year by each large building in the commonwealth that has an account with the distribution company.

[Subsection (d) added by 2022, 179, Sec. 41 effective July 1, 2024. See 2022, 179, Sec. 95. For text of subsection (d) as amended by 2023, 77, Sec. 6, see below.]