How DOES Electric Heat Work?
Fuel-based heating systems are straight forward, right? We blast a fuel source into a combustion chamber, then we expose it to a low flame, enough electricity to disintegrate Zeus, or a really hot heating element, and boom, it combusts, creating heat and exhaust. What about electricity though? We can’t burn that.
Friction is Key
There are a lot of set ups available to create electrical heat. You could use an electrically powered heat pump for example. That’s not really electric heat though, it only works if there’s somewhere to take heat from. It’s electrically facilitated heat. What makes heat directly from electricity?
The short answer is friction. When we move an electrical current through anything, we are moving electrons. The electrons are gong to effectively slide against or impact the molecules in the wire. This causes the electron to lose some energy to those particles, giving them energy, and causing the material to heat up.
Resistance is Futile
The friction in wiring like this is called Resistance. We can measure it in ohms. More ohms means more heat and a lot less current passing through the resistor. Most resistors are small components inside the electronics around your home or office. They can be used to lower currents, divide voltages, and other work in small electronics. A big resistor however, can be the heart of a furnace or portable heater.
A heating resistor like this is going to work one of two ways:
These resistors will become incredibly hot and heat the air around them and anything that directly touches them. Blowing air over them would heat the air in a similar manner to combustion heater and its heat exchanger.
- Infrared Heat
With the right material, a resistor will emit intense photons around it, typically infrared but it might also be a visible glow. This works like heating lamps and will heat the objects that light touches.
The Actual Implementation
There are generally two ways heating like this is gong to be configured in your facility. One the one hand, large electrical furnaces exist. These are almost exactly like a gas furnace, except there’s a resistive heating element that air is being blown over. The other implementation is to forgo the large furnace and instead configure a zone system with essentially individual heating elements in each location needing heat. Unlike a gas heating system, an electric heater’s ‘fuel’ is typically everywhere inside the facility and it’s fairly economical to install multiple, smaller heating units instead of a large one.
Is It A Good Idea?
Using electric heat for your facility is a more complicated question to answer. It depends on local electrical rates and regulations. If electricity is cheaper than heating fuels, then it might be a good approach to take. If the local climate is rarely cool enough to require heating, then an electrical heating system may make sense too. The maintenance costs can be lower as there are fewer parts to maintain and no tanks or pipes to become rusted or corroded over time, and few moving parts.