the first animation demonstrates no solar gain at the summer solstice. a south-facing home can be sheltered from the summer sun with sheltering overhangs. this reduces heat build-up during the day, and shifts the peak cooling load to later in the evening as the sun is going down. the air-conditioning savings can be dramatic. the second animation demonstrates the full solar gain at winter solstice that can be utilized in passive solar design. during the winter, as the sun rides lower in the sky, the sun bathes walls facing southwest, south, and southeast in light — to warm the home throughout the day.