Even a 10-20 year old fridge is very inefficient compared to a modern fridge. It's as easy as looking at energy star ratings.
Do you think the manufacturers aren't gaming those ratings either?
The energy efficiency of fridges over time has definitely not been monotonic either. The ones that use the most were the late 60s-80s models that sacrificed insulation thickness for more interior volume.
>Do you think the manufacturers aren't gaming those ratings either?
Oh cmon, you can't categorically dismiss an entire government program with an offhand comment like that. You need to at least provide some sort of evidence supporting your claim.
The problem with many energy efficiency ratings, including Energy Star and that controversial California "ban gaming PCs" one, are that they are designed around "power consumed for a particular use case", where use case is defined as "watch TV for the household average number of hours per day", not normalized for whether the picture quality was great or poor. In the gaming PC case, there was a bureaucratic formula based on how many ports the computer had, and having lots of ports allowed you to use more energy because it was considered a "high expandability" computer, regardless of whether it was reasonable for the computer with empty extra ports and no different parts to use more power. And it focused almost exclusively on "turned off or standby" power, not power in use.
In the case of TVs, manufacturers game the numbers by rating efficiency "as shipped to the consumer at factory default settings." The manufacturer just sets the brightness to 20%, and throws a warning on the screen if the customer tries to change it, saying "the TV may use more energy". Of course, in the store, the TV is set to Store Mode, which means the brightness is often even higher than 100%, and the TV has a sticker about how efficient it is. Nobody would buy a TV that was dimmed permanently to the Eco Mode, but technically, you can "watch the very dim TV", so it counts.
This means that the composite "energy efficiency score" is not calculated with "output" or "work done" or "function realized" held constant. The text of the standards often does not define exactly the outcomes to be achieved.
Thus, it is entirely possible for a manufacturer to produce products with a degraded functionality in exchange for "better energy efficiency", regardless of whether worse functionality may cause the consumer to use the item for twice as long. (i.e. some government restricting the wattage of vacuum cleaners, which may cause vacuum cleaners to become less effective instead of more efficient, causing increased run time)
In the case of fridges, you might imagine how a manufacturer might skimp on "lasts long", "how much space the fridge takes compared to how much space is inside", and other things like this.
I thought early fridges did surprisingly well because they tended to be smaller and the frost-free mechanisms are wasteful on multiple levels (they're running a heater, and then probably have to run the cooler more to compensate)
Do you think the manufacturers aren't gaming those ratings either?
The energy efficiency of fridges over time has definitely not been monotonic either. The ones that use the most were the late 60s-80s models that sacrificed insulation thickness for more interior volume.