Is it Greener to Use a Roomba or an Upright?


Roomba photo via Dano; Upright photo via Butkaj

When it comes to cleaning the floors, we wondered which is better: A Roomba or a Dyson upright vacuum.

On the one hand, the Roomba runs all the time, cleaning floors like Cinderella and charging up when it runs out of juice. An upright, however, only uses electricity at the specific times you choose to run it. So which is better for the environment and your wallet?We realize that this can quickly become a slippery slope, and it doesn’t take much of brain walk to start trying to factor in the carbon emissions of production for each device, the recyclability, the life span for each of these in the average American household, the source of the electricity used to run each….and on and on.

So we took the KISS method and just looked at the basic numbers: how much do they cost to buy, run, and maintain? TreeHugger Alan Graham used his Kill-A-Watt to test out his Roomba and his Dyson upright to see what might be discovered. Here are the numbers:

Roomba

Roomba takes 3 hours to charge at 30 watts. Total cost to run it once every other day is about $.13 a month. Roomba has a trickle charge to keep the battery topped off at all times. That is 5 watts, and the total cost to keep it plugged in and charged 24/7/365 is $.34 a month or $4.08 a year in electricity.

Also, the battery has needed replacement twice over 3.39 years. Total battery cost has been $118. Further maintenance costs have been two replenish kits running $29 each.
Total cost of ownership so far:

$250 Roomba purchase price
$118 Batteries
$5.64 Electricity per year
$58 Parts
Warranty lasts for 1 year
---------
$443 total cost (cost will vary depending upon electricity rates in different areas and other variables, of course)
Average of $51.76 per year for parts and batteries, and an averaged annual cost of about $130 since purchase

Dyson


The Dyson has a 1400 Watt motor (an average wattage for uprights, which can range anywhere from 1200 to 1800 Watts). Running at 4 hours total a month, the monthly electricity is $.53, or $6.36 a year.

$494 Cost of vacuum
$30 Replacement Brush
$17 Filter
$10 Replacement Belt x2
$6.36 Electricity per year
Warranty lasts for 5 years
---------
$567 total cost (cost will vary depending upon electricity rates in different areas and other variables, of course)
Average of $16.76 per year for parts, and an averaged annual cost of $166 per year since purchase.

Comparing the Numbers
So we can see the cost of maintenance is far less for a Dyson upright, though the initial cost is higher. But the electricity requirements are lower for the Roomba.

If you’re going for less electricity, lower cost, and – let’s be practical – less time wasted running a vacuum cleaner, then the Roomba is your device of choice. While that means you’re responsible for properly recycling batteries about once a year, it also means you're choosing an option that consumes fewer plastics and materials during manufacturing. Also, pay attention to the warranties – the Roomba comes with a one-year, versus the Dyson’s 5-year.

A Proper Comparison
However, also keep in mind this isn't quite a perfect apples-to-apples comparison. As Alan points out, the Roomba is great for getting under furniture and picking up pet dander and small dirt. But it can't handle large pile carpet and doesn't have hose attachments like the Dyson or any upright.

While the decision ends up coming down to what you really need the device to do, it's helpful to have some numbers to compare and see which would be a less expensive and energy intensive way to go.

More on TreeHugger Comparisons:
Biodegradable vs. Recyclable: Which is the Better Packaging Solution?
Are Lucky Charms Better for You Than Granola?
Green Computer Smackdown: Dell Studio Hybrid Versus Advent Eco PC

Tags: Cleaning | Electricity | Energy Efficiency | Plastics