Electric hand dryers need electricity to run that may come from fossil fuels and they could also spread bacteria. Paper towels need a constant supply of trees, but limit the spread of bacteria. So, which is better?
Life Cycle Analysis of Hand Drying Options
Both drying options have different areas of impact, known as phases, including the materials used to make the product, manufacturing, shipping, the impact of the actual use of the hand drying option, as well as the impact of disposal. By looking at some research we can see the impact of each phase as well as the overall impact of each drying option.
There are two popular types of electric hand dryers, ones that blow hot air and ones that blow air at a high speed, such as the Xlerator hand dryer. The impact of electric hand dryers is mostly from their actual use, due to the energy used to dry your hands. The Xlerator high speed dryers are more efficient and dry your hands faster than hot air dryers, so their impact is lower. On the other hand, the impact of paper towels is more spread out across its phases. The most impactful phase is in manufacturing followed by the process of acquiring materials to make paper towels. We can compare the impact of paper towels made with no recycled content to those of paper towels made of 100 recycled content.
Since no new trees are needed to make paper towels made of 100 recycled content, the materials phase drops. However, pretty much all of the other phases are unaffected, since there is just as much manufacturing, shipping, and waste. So the overall benefit of recycled paper towels over non-recycled paper towels isn’t as much as you would expect. We can compare these paper towel options to our hand dryers to see which is better based on how many towels you use to dry your hands as well as how long it normally takes you to dry your hands.
Since the outcome will change based on these different factors the data here is based on an average amount someone needs to dry their hands. You would need about 12 seconds to dry your hands with the Xlerator high speed dryer, about 30 seconds for the hot air dryer, and for paper towels the data is based on two towels. So based on this, the high speed dryer is best, however the impact can change based on the number of towels you use or how long you dry your hands with the electric hand dryer.
The best option when comparing the high speed dryer to paper towels is to use the high speed dryer if you can dry your hands in less than 24 seconds. If you can’t, switch to paper towels, but only if you use one towel and it’s made of 100 recycled content. We can do the same for the hot air dryer. The best option is to use the hot air dryer for 10 seconds or less. If you need more time than 10 seconds, switch to paper towels, but only if you use one towel. If you need more than one towel it would be better to use the hot air dryer for 10 to 20 seconds.
If you’d like help figuring out how this applies to you check out our app. The option that’s best for you could also be influenced by the amount of renewable energy in your area or in your building. If either electric hand drying options is powered entirely by renewables, such as solar power, you will have several minutes before you should switch to paper towels, which is way longer than you will need. If your hand dryer is powered by coal, you have about 12 seconds to use the high speed dryer before you should switch to paper towels manufactured with renewable energy, regardless if they’re made with recycled content or not, although recycled is better. The only way in which two towels is the better option here is if you take longer than 20 seconds to dry your hands and have towels made with 100 recycled content and manufactured with renewable energy. For hot air dryers powered by coal, paper towels will be the better option even if you only take 10 seconds to dry your hands.
Does Composting Paper Towels Make A Difference?
One last thing on the environmental impact. If you’re in a situation where the impact is close between paper towels and hand dryers composting the paper towels can make all the difference. Of course, we also have to consider germs and bacteria. Hand dryers have been known to blow bacteria off of your hands and around the bathroom which isn’t very sanitary. Paper towels are better at limiting the spread, however research studies show that this difference can be eliminated by first washing your hands properly. If you wash off the bacteria with soap and water there is little left to spread and both options can be equally sanitary.
So to recap, overall high speed hand dryers will be the best option in most cases. Hot air dryers will never be a better option compared to high speed dryers and are sometimes better than paper towels. Paper towels are the better option in areas that are powered mostly by fossil fuels compared to the hot air dryer but not to the high speed dryer if you dry your hands in less than 12 seconds and, by properly washing your hands, you can make both drying options a sanitary option.
If you’d like to learn more about how to live a more sustainable life, check out some of the other comparisons I’ve made. For example, how do you know when to use a dishwasher or wash by hand? What able electric cars vs gas cars? Or baths vs showers? If there is an article you don’t see, please feel free to contact me and let me know!