Energy efficiency retrofits get pitched with confident payback numbers a lot more often than they get evaluated honestly after the fact. Some retrofits genuinely pay for themselves in a reasonable window; others are a much longer bet than the sales material suggested, and a few simply do not make sense for a given building. Here is what we actually tell property managers when they ask whether a specific upgrade is worth it.
Economizers
An economizer brings in outside air to provide free cooling when outdoor conditions allow, reducing compressor run time. In much of the country this is one of the higher-value retrofits available. In Central Florida, it is a genuinely mixed case — Orlando’s climate has plenty of hot, humid hours where outside air is not usable for free cooling without adding a dehumidification load, which cuts into the savings economizers are known for elsewhere. That said, Orlando does get enough mild, dry stretches — particularly in winter months and shoulder seasons — that a properly controlled economizer on a building with long operating hours can still see a payback in the 3 to 6 year range. A building open only standard business hours with minimal shoulder-season benefit will see a longer payback, sometimes not worth the retrofit at all.
VFDs (variable frequency drives)
VFDs on supply fans, condenser fans, or pumps let motors run at the speed the load actually calls for instead of full speed with mechanical dampers or bypass throttling absorbing the difference. This tends to be one of the more reliable paybacks in the efficiency retrofit category, because fan and pump energy scales with the cube of speed — even a modest reduction in average operating speed produces a disproportionate energy savings. On equipment that runs long hours with variable load, such as a building with fluctuating occupancy through the day, VFD paybacks in the 2 to 4 year range are realistic. On equipment that already runs at a fairly constant near-full-load condition most of the time, the payback stretches out significantly because there is less variable load to capture savings from.
Controls upgrades
Modern building automation and smart thermostat controls that add scheduling, setback, and demand-based ventilation typically have the shortest payback of the three categories here, often 1 to 3 years, because the cost of the retrofit itself is usually lower relative to the savings captured. A building currently running on manual overrides or a decades-old pneumatic control system with no real scheduling often sees immediate, measurable savings simply from proper setback during unoccupied hours — something a lot of older buildings are simply not doing at all.
How Orlando’s climate and utility rates factor in
Two things specific to this market matter more than most national payback estimates account for. First, Orlando’s long cooling season means equipment runs more total hours per year than in milder climates, which generally helps payback math for anything that reduces run-time energy — more hours of operation means more hours to capture savings. Second, actual commercial utility rates vary meaningfully by provider and rate schedule in the metro, and demand charges specifically can make VFDs and controls upgrades that reduce peak demand pay back faster than a simple kWh-savings calculation would suggest. Any real payback estimate should use your building’s actual utility bill and rate structure, not a generic assumed rate.
When a retrofit doesn’t pencil out
A few situations where we will tell a property manager honestly that a retrofit is not worth pursuing yet:
- A building nearing a full RTU replacement anyway. If the rooftop units are past 12–15 years old, it usually makes more sense to fold efficiency gains into the replacement equipment’s specification — see our RTU replacement cost guide — rather than retrofit controls onto equipment that will be replaced within a few years anyway.
- Short remaining lease term. A retrofit with a 5-year payback on a building where the tenant has 18 months left on their lease is a harder case to justify unless the ownership plans to hold the equipment value long-term regardless of this tenant.
- Very low run-hour equipment. A unit that runs only a handful of hours per week has little energy cost to capture savings from in the first place, regardless of how efficient the retrofit itself is.
How we approach a retrofit quote
We look at your actual utility usage, the specific equipment and run-hour pattern in your building, and give you a realistic payback range rather than a single optimistic number pulled from a manufacturer’s marketing sheet. If a retrofit does not make sense for your building right now, we will say so — a customer who trusts our numbers on a retrofit that does not pay off is a customer who calls us again for the one that does. Full detail is on our energy efficiency retrofits page.