Section 15. A vehicle, whether stationary or in motion, on a public way, shall have attached to it headlights and taillights which shall be turned on by the vehicle operator and so displayed as to be visible from the front and rear during the period of 1/2 hour after sunset to 1/2 hour before sunrise; provided, however, that such headlights and taillights shall be turned on by the vehicle operator at all other times when, due to insufficient light or unfavorable atmospheric conditions, visibility is reduced such that persons or vehicles on the roadway are not clearly discernible at a distance of 500 feet or when the vehicle's windshield wipers are needed; provided further, that this section shall not apply to a vehicle which is designed to be propelled by hand; and provided further, that a vehicle carrying hay or straw for the purpose of transporting persons on a hayride shall display only electrically operated lights which shall be 2 flashing amber lights to the front and 2 flashing red lights to the rear, each of which shall be at least 6 inches in diameter and mounted 6 feet from the ground. Upon the written application of the owner of a vehicle and the presentation of reasons therefor the department may, in writing, in such form and subject to such requirements as it may elect, and without expense to the applicant, exempt said vehicle from the provisions of this section for such period of time as said department may elect. A violation of this section shall not be deemed to be a conviction of a moving violation of the motor vehicle laws for the purpose of determining surcharges on motor vehicle insurance premiums pursuant to section 113B of chapter 175.