Now here’s why it doesn’t matter:
The carbon emissions of drying hands is between 3 and 20 grammes of CO2e (all greenhouse gases converted into a carbon dioxide equivalent). Assuming you wash your hands on average twice a day whilst at work (and that you work for approx 245 days a year) the annual handwashing carbon emissions of each employee will be between 1.5kg and 10kg each year.
Now consider that the average carbon footprint of an employee whilst at work is 5 tonnes (worked out as the business’s carbon footprint divided by the number of staff working there). That’s 5,000 kg. So handwashing represents roughly 0.1% of an employee’s footprint.
For an average business each Airblade will cost around £30 a year to run (each unit uses around 349 kWh per year, or 1 kwh per day according to this information).
So really, the question shouldn’t be which is lower carbon out of paper towels and hand dryers. The question should be what is more important than either of those things in terms of business carbon emissions and costs. And the answer is almost everything.