Section 18. An insurance company incorporated under the laws of the commonwealth or authorized to transact business in the commonwealth, instead of investing its funds in the stocks, bonds and other securities of a corporation organized under section three, or otherwise investing in or participating with an individual or entity authorized to undertake and carry out or acquire projects under this chapter, may with the approval of the commissioner of insurance, itself undertake on land owned or to be acquired by it one or more projects under this chapter, or acquire projects or any severable portion thereof from corporations, individuals or entities authorized to undertake or acquire projects under this chapter, and the provisions of this chapter, specifically including the powers granted by sections six A and eleven and the procedures set forth in section eighteen B shall, so far as apt, be applicable to such company and such projects, excepting the following:

(a) Section three shall not be applicable to such company; but if an insurance company undertakes more than one project, the accounts for each project shall be kept separately, and the income of one project shall not be expended upon or for the benefit of another project.

(b) The application for the approval of a project shall be submitted by the directors of the insurance company and an application so submitted shall be subject to all of the provisions of this chapter relative to applications by the persons who have executed an agreement of association.

(c) So much of section six as relates to the agreement of association shall not be applicable to such company.

(d) Section seven shall not be applicable to such company.

(e) So much of section eight as provides that ''Every such corporation shall be deemed to have been organized to serve a public purpose'' shall be construed to mean ''Every such project shall be deemed to have been undertaken to serve a public purpose''.

(f) Section nine shall not be applicable to such company; but such company shall not receive or accept for its general purposes as net income from a project any sum in excess of eight per cent of the amount invested by it in such a project for each year in which it owns or has owned the project, except that, if in any year it has so received a sum less than the aforesaid eight per cent, it may so receive in a subsequent year or years additional sums not exceeding in the aggregate such deficiency without interest. Nothing in this section shall be applicable to the payment of dividends out of profits from the sale of the capital assets of the corporation.

(g) So much of section ten as applies to the taxation of a corporation organized under section three shall apply to an insurance company only with respect to a particular project or to particular projects, and such company shall remain subject to all other taxation imposed by law with respect to its other activities and property. If an insurance company occupies or uses one or more parts of a project for purposes of its business not directly related to the construction, alteration, maintenance, repair, operation or management of such project, the gross income from such business shall not be included in computing its gross income from all sources but in lieu thereof such amount as the insurance company and the housing board shall in each year not later than June thirtieth agree, or in the event of their failure to so agree, the commissioner of insurance shall determine, to be the fair rental value for such year of the floor area so occupied or used shall be included in computing gross income from all sources.

(h) The term ''housing board'' as used in the last paragraph of section eleven shall be deemed to mean the commissioner of insurance whether the project is in Boston or another city or town.

(i) So much of section fifteen as relates to reducing the indebtedness of a corporation shall apply only to indebtedness incurred in connection with a project. The term ''housing board'' as used in said section fifteen except the first time it appears in clause (5) shall be deemed to mean the commissioner of insurance whether the project is in Boston or another city or town.

(j) So much of section sixteen as provides that under certain circumstances a corporation shall have all of the rights and privileges of a corporation organized or subject to chapter one hundred and fifty-six shall be construed to mean that an insurance company may under like circumstances lawfully continue to hold the project but shall in other respects be subject to all of the obligations and duties of an insurance company.

(k) The period of fifteen years or such further time as may be provided under section ten as set forth in sections ten, sixteen and sixteen A shall be computed for a particular project from the date of approval of such a project.

The words ''insurance company'' or ''such company'', as used in this section shall be deemed to include a group of insurance companies.