A single candle typically generates approximately 80 BTUs (British Thermal Units) per hour. However, it's important to note that this is a rough estimate and the actual heat output can vary based on factors such as the type of candle, its size and the materials used.
For instance, larger candles or those made from specific materials like beeswax or soy may produce more heat. Therefore, while a single candle can provide a small amount of warmth, multiple candles would be required to significantly increase the temperature of a room.