Take a candle and place it in a dish. Light the candle. Pour some water into the dish. And then cover the candle with a glass vessel. When the candle burns it will take up all the oxygen in the glass vessel.
Once this is over the candlelight will die. You will see that water has risen in the glass vessel. This is because of the vacuum created inside by the absence of oxygen.
Heat can be produced by just rubbing together your hands. And you should know that in a light producing source, more than 90% of the energy is radiated as heat. To check this fact, just keep your hand near a light shade. You will feel the heat. If you do some study, you will find that bulbs with low watt power produce lesser heat than those with higher watt power.