What is thermal energy
Energy may come in many different forms, but there are only five basic types: potential, kinetic, chemical, nuclear and thermal. Of the five, thermal energy may be the least talked about. It is part of the total internal energy of a system or sample of matter and is responsible for the temperature of the system or sample. In plain English, thermal energy is heat energy.
Why is this important? What can we possibly do with energy from heat? As it turns out, we wouldn’t even be here without thermal energy. The majority of the energy the Earth gets from the sun doesn’t come as light, but as heat. Thermal energy from the sun is responsible for the generally warm and hospitable climate we enjoy. It fuels weather patterns and changes in the atmosphere.
You can experience the effects of thermal energy in your everyday life as well. Turn on your stove and hold your hand a few inches above the flame or the electric burner. The heat you feel is thermal energy being transferred to the room at large.
About now you’re probably wondering how we can use thermal energy in an alternative energy system. The most common application is in cooking. Solar cookers collect heat from the sun and use it to bake or slow cook food such as breads and stews. Some of them get quite hot –several hundred degrees.
Another way to use thermal energy in cooking is to use a haybox cooker. This is a heavily insulated oven. They were so named because the first ones were boxes surrounded by bales of hay. Many farm families still utilize this form of cooker. The meal to be cooked is heated to a boil using some other fuel source and then immediately transferred into the haybox cooker. The insulation keeps it from cooling down, and the food continues to cook. Several hours later it is ready. Haybox cookers were the original Crockpot!
The second common application of thermal energy is in heating. Both conventional and alternative energy systems utilize thermal energy to help heat buildings. Radiant floor heating is a good example. Hot liquid is pumped through tubes installed under the floor of a building. The liquid heats the tubes and the floor, which then warms the building.
A better-known example is the woodstove. Woodstoves and fireplaces have been used for heating purposes for hundreds of years. Older models weren’t very energy efficient or clean, but newer models are much better. They are airtight and produce very little air pollution. In addition, wood is an infinitely renewable resource when it is managed right.
Thermal energy is one of the most important types of energy, and it is easy to utilize i
n alternative energy systems.