Have you ever sat in front of a heat lamp, worn night vision goggles, or reheated food in a microwave? If so, you’ve used radiant energy. The same goes with listening to the radio or getting an X-ray at the hospital. Radiant energy is among the most abundant types of energy on the planet, and our lives just wouldn’t be the same without it.
But is radiant energy renewable and can you use it to improve energy efficiency at home? And how many types of radiant energy are there?
Come along and we’ll go on a tour of the electromagnetic spectrum — which is where you’ll find all seven types of radiant energy in the universe.
What Is Radiant Energy?
The definition of radiant energy can be a bit of a head-scratcher for those of us who aren’t scientists. Lehigh University describes it as “electromagnetic energy that travels in transverse waves.” But what does that mean? We’re not talking ocean waves here — these are electromagnetic waves made up of photons, a subatomic particle.
We can actually detect some types of radiant energy with the human body. Our eyes can detect visible light, and our skin can detect infrared energy in the form of heat.
But other types of electromagnetic energy can only be observed using specialized equipment like radio telescopes.
Where Does Radiant Energy Come From?
The ultimate source of radiant energy is the movement of atoms at a molecular level. But on a practical level, where does radiant energy actually come from?
One of the most common examples of radiant energy is solar radiation, which travels to the Earth in the form of light energy. Stars and black holes also produce radiant energy in the form of gamma rays.
Nuclear energy itself isn’t a type of electromagnetic energy, but the process of nuclear fusion can be used to produce radiant energy. We can produce other forms of radiant energy using devices like microwaves, light bulbs, and infrared heat lamps.
Do Humans Have Radiant Energy?
Yes, human beings produce radiant energy, although it’s pretty weak compared to others sources of radiant energy.
In fact, all living things produce electromagnetic radiation in the form of heat, or thermal energy. It mostly falls on the infrared part of the spectrum, so you can’t detect it with the naked eye. But you can see humans and animals with thermal imaging devices.
What Are the 7 Types of Radiant Energy?
Before we get into more practical uses for radiant energy, we need to pause for a quick overview of the electromagnetic spectrum. That’s because the usefulness — and safety — of radiant energy depends on where it falls on the spectrum. Let’s review the seven types of radiant energy in more detail.
Radio Waves
Radio waves need no introduction: we use them to listen to music on the radio and communicate with each other using walkie-talkies. They’re also used in some types of space telescopes and in radio detection and ranging (RADAR) devices.
Microwaves
Microwaves have a slightly longer wavelength than radio waves, so they’re a little more powerful. We can use them to cook food in microwave ovens, but they also play a key role in Wi-Fi and satellite communications.
Infrared Waves
Infrared waves are produced by heat lamps, infrared saunas, campfires, and even the human body — basically, anything that produces heat. Some snakes can “see” infrared light, but human beings need to rely on thermal imaging devices to observe it.
Visible Light
Visible light is the only type of radiant energy that humans can see with the naked eye. The exact wavelength determines which color we observe, with red at one end of the spectrum and violet on the other.
Ultraviolet Light
Ultraviolet light is just outside the range of human vision, but some types of insects can detect it — and plants need it for survival. That’s why indoor grow lights are designed to provide a healthy amount of UV radiation to support photosynthesis. Too much exposure to UV light, however, is harmful to both humans and plants.
X-Rays
X-rays are used in medicine because they can pass through certain types of tissue more easily than others. That’s why skin, bones, and soft tissue appear so different in medical imagery. But like UV rays, they can be harmful to the human body in large quantities.
Gamma Rays
Gamma rays have the highest wavelength of all types of radiant energy, so they’re the most harmful to humans. But since they come from stars and other space objects, the earth’s atmosphere filters most of them out before they reach us.
Is Radiant Energy Safe?
Whether or not radiant energy is safe for humans depends on what type of energy it is and how much exposure we have to it.
A wave’s frequency is measured in Hertz (hz), which tells you the number of cycles per second. Higher-frequency waves have shorter wavelengths and transmit more energy, to the point where they can remove electrons from atoms in the human body.
This is called ionizing radiation, and it’s found in solar radiation, gamma rays, X-rays, and a few other types of electromagnetic energy. Too much exposure to this type of energy can increase the risk of cancer.
Non-ionizing radiation occurs at the lower end of the spectrum, including radio waves, microwaves, and infrared radiation. This type of radiation doesn’t have enough energy to damage the atoms in the human body, so there are no health risks.
That explains why we need to protect our skin from ultraviolet radiation but not from the radiant energy that comes from radio waves or infrared heaters.
Can You Convert Radiant Energy Into Electricity?
Radiant energy is a type of kinetic energy, and so is electrical energy — so does that mean you can turn one into the other?
In short, yes. The laws of thermodynamics state that you can convert one form of energy into another. But electrical energy operates differently than radiant energy, and relies on the movement of electrons rather than photons.
One way to convert radiant energy into electricity is to use solar panels: these devices capture solar energy and turn it into electrical energy.
This also works in the other direction: when you plug in a heater, use the microwave, or even turn on a light bulb, you’re converting electricity back into radiant energy.
Can You Store Radiant Energy?
Storing radiant energy is a little trickier, because most energy storage devices, such as batteries, use chemical energy, which is a type of potential energy. That’s the opposite of kinetic energy, which is always in motion.
In order to store radiant energy, you’ll need to convert it into chemical energy first. You can use devices such as a lithium-ion battery to store this type of energy.
What Is Radiant Heating?
As we’ve already seen, electromagnetic waves all produce heat to varying degrees. So does that mean you can use radiant energy to heat your home?
Yes, but when we talk about radiant heating, we’re talking about one specific part of the electromagnetic spectrum: infrared radiation. Leaving the radio on might produce a little bit of radiant heat, but not enough to warm up the room!
For that, you’ll need to install a radiant heating system in your home — either a wall panel or a floor installation. These systems use electrical cables or hydronic tubes to deliver heat more efficiently than forced-air systems.
Does Radiant Heat Warm the Air?
Radiant heating relies on the natural movement of air: as heat rises from the floorboard or wall panel, it circulates naturally and is evenly distributed throughout the room.
In contrast, forced-air systems blow hot air into or around the room, which can be less energy-efficient, especially if the room is large and the vents aren’t spaced properly.
Also, forced-air systems tend to lose heat through gaps in the ventilation system, and they may be more uncomfortable for allergy-sufferers if they generate dust.
Is Radiant Energy Renewable?
Radiant energy describes the type of energy, not necessarily the source. So we can say that some sources of radiant energy are renewable and others aren’t.
When you plug in an infrared heater into the electrical grid, it could be powered by wind, coal, natural gas, solar power, or a combination of the above. When it comes to floor installations, these systems are usually powered by either electricity or gas.
So if you want to reduce your emissions, you’ll need to be more selective about where you get your electricity from, such as a green energy plan that offsets your usage.
Can Radiant Heating Save You Money?
Radiant heating systems can cost more to install than forced-air units, but they can save you money over the long-run by lowering your electricity bill.
In part, that’s because HVAC units are energy vampires that keep drawing power even when they’re in standby mode. But it’s also because radiant heating systems are more efficient, so you may not need to run them continuously to keep your house warm.
It’s also worth noting that hydronic systems, which use hot water from the boiler to heat your home, tend to be more cost-effective than electrical heating systems, which could result in increased heating bills if electricity prices rise.
Use Your Knowledge to Power Your Home More Efficiently
Radiant energy is all around us and knowing just a bit more about it can help you in various ways. Not only is it fascinating to delve into the scientific aspects of this ubiquitous force but it’s also practical for making more informed decisions about your own energy usage.
With energy costs rising in the U.S., you can take charge of your energy bill by reducing your home energy usage and choosing energy-efficient appliances. And remember, if you live in Texas, you may be able to switch power suppliers to get a better deal.
Amigo Energy offers electricity plans in Texas for all homes and lifestyles. Whether you want to lock in competitive rates, or get free kilowatt-hours on evenings and weekends, simply enter your ZIP code to find the most cost-effective plan for you.
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