A couple of years ago, a study found that paper towels are the least green way to dry your hands. On top of that, they need to be constantly replaced and thrown away – in 2011 used paper towels accounted for a whopping 2% of total landfill contents in the US.
We appreciate 2% doesn’t sound like a “whopping” figure, but it represents about five million tons of discarded paper towels.
A good energy-efficient hand dryer, on the other hand, keeps the cost of running a public space down. But the initial expense is much higher than a pack of paper towels – what, exactly, are architects and designers paying for when they buy an eco-friendly hand dryer?
Sustainable Design for an Everyday Appliance
It’s something we hardly ever think about – but we all need hand dryers, don’t we? Without going into too much detail, we all wash our hands in the bathroom after we use it. And in a mid-sized to large public space, there are a lot of public bathrooms. Which means a lot of hand dryers.
Which in turn means a great deal of carbon emissions, not to mention a great deal of cost. So how are manufacturers trying to reduce the impact of all that energy usage?
The most obvious way to reduce energy demands is to design a product so it consumes energy over a shorter period of time – only when it’s needed. That’s the same thinking behind motion detectors and thermostats.
So modern automatic hand dryers have convenient “no-touch” sensors that activate the heat and air when hands are placed near it – usually underneath the vent. This has the added benefit of protecting us from bacteria – there’s no button to be pressed by a lot of people every day.
A higher airflow also means that hands are dried faster, so that sensor is active for less time. In terms of design, this can mean a smaller vent size that increases the speed of the air moving through it, or a higher Specific Fan Power (SFP) rating.
And then when hands are taken away from the sensor, the heat element is isolated as soon as possible.
A Low-Cost but Highly Energy-Efficient Hand Dryer
The trouble is, high-end items like the Dyson Airblade and its many (many) copycats cost up to £1000, which can offset those savings significantly. Besides, they’re incredibly noisy – and in, say, an office space, that can pose a real problem.
The HD900W is a high-pressure hand dryer that implements some of the sustainable design principles outlined here. It promises to dry hands in 12-15 seconds, with a fan speed of 90 metres per second, and for half the wattage of equivalent hand dryers in the store. It incorporates an IR sensor with a cut-off switch at the 1-minute mark, and deactivates within one second.
But it doesn’t come with the price tag usually associated with eco-conscious design! The initial investment won’t be such a dent on the finances, and the lifetime running costs are significantly lower. For public spaces like museums and office buildings, the choice is more than clear.