Posted by GoodCooling Team
Before a company invests in new cooling technology, a sober business question usually arises: when will the purchase have paid for itself? Unlike pure comfort decisions for private use, investment decisions in a commercial environment require a reliable calculation that can also be justified to management, controlling or investors. In this article we show you step by step how to calculate the payback period of an evaporative air cooler and which factors shorten or lengthen the payback time.
Such a calculation is worthwhile not only for a new purchase, but also when you are replacing existing cooling technology or buying an additional unit for a new area. The clearer the figures, the easier the decision – and the more convincingly it can be communicated internally.
What Does Payback Mean for an Evaporative Air Cooler?
The payback period describes the time after which an investment has financed itself through the savings or income it generates. For an evaporative air cooler, the saving usually results from a comparison with an alternative – mostly an air conditioner, or the previous decision not to cool actively, with the resulting follow-on costs (e.g. productivity losses on hot days; see also our article on the electricity cost comparison).
The Formula for the Calculation
The basic formula is:
Payback period (months) = purchase cost ÷ monthly saving
The monthly saving usually consists of the difference in running costs, such as the electricity costs saved compared with an air conditioner, reduced maintenance costs or avoided investment in structural air conditioning.
Worked Example
Let us assume a commercial evaporative air cooler costs €900 to buy. Compared with a comparable portable air conditioner, the business saves about €45 per month during the cooling season through lower electricity consumption (see the basis of calculation in our article on the electricity cost comparison). In addition, maintenance costs for a refrigeration circuit of an estimated €10 per month, calculated pro rata over the year, are eliminated.
This gives:
€900 ÷ €55 saving per month ≈ 16.4 months
In this example, the purchase therefore pays for itself within a little more than one cooling season plus part of the following season. Please note: this is a simplified worked example. For your own calculation, use your actual purchase costs, hours of use and electricity prices.
Factors Influencing the Payback Period
- Intensity of use: The more hours per day and the more days per year a unit is in use, the faster the investment pays for itself.
- Room size and number of units: Larger areas may require several evaporative air coolers or more powerful models – this affects both purchase costs and savings potential.
- Regional climate: In regions with long, hot summers, the investment is spread over more hours of use per year.
- Electricity price trends: Rising energy prices tend to shorten the payback period compared with more energy-intensive alternatives.
- Avoided investment costs: If buying a mobile evaporative air cooler avoids structural air conditioning with installation costs, this further improves the economic calculation.
Practical Examples from Different Industries
The specific payback period differs depending on the area of application:
- Hospitality: In dining rooms and kitchens with high heat generation, all-day operation during the season leads to a comparatively fast payback, as the hours of use are high.
- Workshops: In workshops with changing occupancy and open doors, installing structural air conditioning often makes no sense – here the flexible, ready-to-use solution pays off particularly well.
- Warehouses and industry: In large halls with high air volume, the purchase cost per square metre is put into perspective, as central air conditioning would often be uneconomical or technically hardly feasible here.
These examples serve to illustrate typical orders of magnitude and do not replace an individual calculation for your business.
Additional Economic Benefits Beyond Pure Electricity Costs
In addition to the direct cost saving, there are further factors that have a positive effect on profitability but are hard to put a euro figure on:
- No structural work, no permits, no downtime due to installation
- High flexibility – units can be moved between sites or rooms as needed
- Lower maintenance effort compared with refrigeration-circuit systems
- Possible productivity benefits from a more pleasant working climate on hot days
Payback Is Not Everything: Looking at Total Cost of Ownership
For a complete economic assessment, in addition to the pure payback period it is worth looking at the so-called total cost of ownership, i.e. the total costs over the entire service life of a unit – usually several years. Purchase, operation, maintenance and an estimated lifespan are considered together. An evaporative air cooler with lower purchase costs and low maintenance effort often comes out even better in such a multi-year view than the pure payback period would suggest at first glance, since the ongoing savings continue year after year while the purchase is incurred only once.
Frequently Asked Questions
After how long in use does buying an evaporative air cooler pay off at all?
As a rough rule of thumb: the more days a year cooling is actually needed, the faster the investment pays for itself. With a typical cooling season of several months with regular operation, the payback period is often in the range of one to two seasons.
Should I calculate payback against air conditioning or against no cooling at all?
That depends on your actual alternative. If you are planning an air conditioner anyway, the comparison with that makes sense. If, on the other hand, the previous decision not to cool actively is up for debate, you should also include possible follow-on costs such as productivity losses or discomfort among employees and customers.
Does the payback period change with rising electricity prices?
Yes. Since the ongoing saving compared with a more power-hungry air conditioner rises with the electricity price, the payback period tends to shorten further the more expensive electricity becomes.
Do I have to calculate payback for each unit individually?
With several units for different rooms, it is advisable to run the calculation separately per room or per unit type, as duration of use and room size can differ by area. This gives you a differentiated basis for your investment decision instead of working with a rough average.
Should I update the calculation every year?
Since electricity prices and usage habits can change, it makes sense to check the calculation once after the first full season using the actually measured values and adjust it if necessary.
Conclusion
The payback period of a commercial evaporative air cooler can be reliably estimated with a few key figures. In many practical cases it is in the range of one to two cooling seasons – depending on use, region and the chosen basis of comparison. Use the formula presented to put your own investment decision on a solid numerical footing.
An overview of suitable models for different business sizes can be found in our private & small businesses section and under all products.
