Efficient lamp with envelope having elliptical portions

A lamp includes a light transmissive envelope comprising two spaced apart elliptical portions that together form a hollow interior. The envelope has sealed end portions. Leads are in electrical contact with the filament near the end portions of the envelope for providing power to the lamp. There is a central portion of the envelope that spaces apart the elliptical portions. An electrically conductive filament is disposed in the interior of the envelope. The filament includes coiled-coil portions disposed in the elliptical portions in a coiled-coil shape and a single coil interval portion disposed between the coiled-coil portions at the central portion of the envelope. At least one filament support positions the filament near a center of the envelope. Gas is contained in the interior of the envelope.