Remove the orange portion of the orange peel using a vegetable peeler. Cut peel into strips. Squeeze juice from orange; discard seeds and pulp. In a 3-1/2- to 5-quart slow cooker combine orange juice, cranberry-raspberry juice, and sugar substitute.
For spice bag, cut a 6- or 8-inch square from a double thickness of 100-percent cotton cheesecloth. Place the orange peel, cinnamon, star anise, and whole cloves in center of cheesecloth square. Bring corners of cheesecloth together and tie with a clean cotton string. Add to slow cooker.
Cover and cook on low-heat setting for 5 to 6 hours or on high-heat setting for 2 1/2 to 3 hours. To serve, discard spice bag. Ladle cider into cups. If desired, garnish with additional orange peel. Makes 10 (6-ounce) servings.