In residential zones and in other zones where the use of the property is residential, all accessory equipment, including any ground-mounted mechanical equipment associated with and necessary for operation, including an enclosure for batteries and storage cells, but not including solar panels, shall be screened so as not be visible from the street. In all other zones, all such accessory equipment shall be enclosed with a six-foot high fence or evergreen plantings. A separate building for the accessory equipment is permitted as an accessory structure, which structure shall be subject to the zoning requirements related to accessory structures and may not exceed 140 square feet or more than eight feet in height.