Operating Costs of Air Purifiers

Until recently, we had a BlueAir 211+ in each bedroom.

I was interested to understand the total annual cost of running these air purifiers. While the HouseFresh review says it’s about $275 per year, I ran the numbers myself, for three reasons:

1. Their calculation is based on an electricity price of 17.7¢ per kilowatt-hour, whereas in British Columbia, the price is only 14.08¢.

2. Their calculation assumes the air purifier will run the entire year at full blast (57.2 watts), but I only turn them on to full blast at night, and then turn them down each morning to the lowest setting (27.6 watts). This means I run the unit on high for half the day and on low for the other half, averaging 42.4 watts.

3. Their calculation assumes you are buying the official replacement filters from BlueAir. I, however, generally buy after-market alternatives on Amazon, usually for about $43. They may not be quite as good, but I have an AirThings View Plus in each room; I would notice severe underperformance.

Notes:

1. All prices in are in Canadian dollars (CAD).

2. Electricity usage measurements were taken via my Kill A Watt meter.

Therefore, my total annual cost of running each BlueAir 211+ is:

Electricity = 42.4 watts × 24 hours per day × 365 days per year / 1000 watts per kilowatt
            = 371.424 kilowatt-hours

Electricity Cost = Electricity × Price of Electricity
                 = 371.424 kilowatt-hours × $0.1408 per kilowatt-hours
                 = $52.29

Filter Cost = Filters per Year × Price of Filter
            = 2 × $43
            = $86

Annual Cost = Electricity Cost + Filter Cost
            = $52.29 + $86 
            = $138.29

With an annual cost of nearly $140 per unit, I began looking for a more economical solution. The review of the Northbox 6XL caught my attention for three reasons;

1. According to HouseFresh, it’s a better air purifier.
2. It appeared to be much cheaper to run.
3. I like that, unlike the BlueAir 211+, it has no ionizer.

After some consideration, I ordered two of them, along with a 4-pack of 3M Filtrete MPR 2200 filters for $60 from Costco. Everything arrived and was quickly assembled. The power consumption is even lower than I expected; it only uses 11.3 watts.

My total annual cost of running each Northbox 6XL is therefore:

Electricity = 11.3 watts × 24 hours per day × 365 days per year / 1000 watts per kilowatt
            = 98.988 kilowatt-hours

Electricity Cost = Electricity × Price of Electricity
                 = 98.988 kilowatt-hours × $0.1408 per kilowatt-hours
                 = $13.94

Filter Cost = Filters per Year × Price of Filter
            = 2 × $15
            = $30

Annual Cost = Electricity Cost + Filter Cost
            = $13.94 + $30 
            = $43.94

At an annual saving of about $105 per unit, after sales tax, the initial cost of the air purifiers will be payed back in about 3.5 years. Given their modular design, I anticipate they will last many years, since I can easily replace any broken parts.

I will have to think about whether I want to order a couple more for the kitchen and living room.