When I was walking into a Home Depot store today, I noticed a peculiar display towards the entrance. The item being displayed was a radiometer. Radiometers are very simple devices enclosed inside a glass sphere. When light is shown into the sphere, the device inside the sphere spins! To give you a better idea of what this device looks like, here is a picture:
Home Depot’s basic argument was that buy placing these spheres in your home they could convert either sunlight or artificial light into kinetic energy (motion) instead of heat, therefore saving you money on your air condition. This claim made me raise my eyebrows a little bit, so I decided to investigate the matter further. I couldn’t find any websites to confirm or debunk Home Depot’s claims, so I decided to write this article.
First things first, radiometers are small, just slightly larger than the size of your palm. It’s very unlikely that something that small will be able to make a significant impact on the temperature inside your home, so you would have to buy a lot of them. More importantly, however, is that the radiometers on display squeaked! They sounded just like a squeaking bicycle wheel, which would be far too annoying to put into your home. So already, I’m going to give my immediate thumbs down radiometers.
Now it’s time to look into the issue of whether or not they can actually save you any real money. We can address this in two parts. The majority of light which comes into your home during daytime hours is through the windows. If you decide to place radiometers on your window sills, they may be able to reflect a small portion of sunlight out of your home. Unfortunately, this is not enough to make a significant difference. At any given time, the reflective area of a radiometer is only a couple square inches at most, whereas light coming into your window is many thousands of square inches! Therefore, a single radiometer is unlikely to absorb more than one tenth of one percent of the total amount of energy coming in through a single window. Therefore, it is impossible that radiometers could ever really save you money by reflecting and absorbing sunlight. If you have too much sunlight coming in through your windows, the best and most common thing people do is have white blinds and close them all the way. This reflects most of the sun’s energy, thus saving you money.
At night, typically the outside air is much cooler, so if you want your apartment or home to be cool, just open your windows. If you don’t have good insect screens, then you can simply open up your blinds. This will let light out of your home, and therefore let head out of your home. Again, the surface area of radiometers is so outrageously tiny that it shouldn’t even be considered as a viable way to reduce your air conditioning bill.
The last thing I wanted to address was the actual cost of the device. The cheapest one I could find on the internet was about 10 dollars, although they go as high as fifty dollars. I view these radiometers as interesting gift ideas to young children, or perhaps to physics teachers for class demonstrations. It’s important to remember that you could have one of these in your home for twenty years, and it still wouldn’t pay itself off because it can’t absorb or reflect very much energy.
In conclusion, keep your eye out for new, money saving technologies, but also be somewhat skeptical. Before going outside and spending your money on a device, the best thing you can do is a little research beforehand to make sure you’re making a wise investment. What really strikes me about this whole experience is that my local Home Depot was attempting to sell them as a viable energy saving device, when in fact, it is impossible for the devices to save any measurable amount of money. I usually put trust in large companies because I know they have many people who evaluate a product before selling it. An important lesson to be learned here is that just because a company is large doesn’t mean it’s always right, and certainly doesn’t mean the company is looking after you. Radiometers are just another expensive gimmick designed to take money out of your wallet.
Posted under Avoiding Scams, Saving Money
This post was written by admin on September 7, 2008