Refrigeration is a major user of electricity and, from time to time, 
gadgets come on the market offering major energy savings. Truth be told, new refrigerators have seen a roughly 2/3rds drop over the past 20 years. Yet, they can be more efficient. Well, we are being told that the eCube is the solution. According to the Guardian,
It is made of wax, is barely three inches across and comes in any colour you like, as long as it’s black. And it could save more greenhouse gas emissions than taxes on gas guzzling cars, low energy light bulbs and wind turbines on houses combined. It is the e-cube, and it is coming soon to a fridge near you.
The eCube operates, according to the web promotion, on the basis of reducing the number of refrigeration cycles. How does it work?
The eCube consists of a food simulant contained in a double-skinned enclosure. The food simulant mimics food temperature at around 10mm below the surface. Due to its specific design, the eCube ensures that refrigeration keeps food at the correct temperature.
Thus, in essence, the eCube insulates the thermostat from sensing air temperature but, instead, seeks to force the thermostat to mimic the temperature of food in the refrigerator.
When fitted to the thermostat sensor, which controls the compressor, the eCube significantly reduces the frequency of the refrigeration cycles as they are now based on food temperature rather than fluctuating air temperature.
Again, the refrigeration cycles will be reduced …
By using the eCube as a cycle control mechanism, refrigeration cycles last longer but can be reduced by as much as 80%.
80% … that is a big number … are they suggesting that they will cut energy use by 80% … that starts to get people interested.
For example, a Dairy Case air cycles 3 minutes on, 2 minutes off = 12 cycles per hour. With an eCube fitted, the cycles change to 8 minutes on, 7 minutes off = 4 cycles per hour. This equates to a 66.7% reduction in starts.
No … no … well … this case shows reduction from 36 minutes of refrigerator operations to 32. Noticeable, over 10%, but far from 80%. But, the cycles have been reduced by 66%.
So, does it matter?
As the start-up of a refrigerator compressor uses 3 times more power (i.e. start-up 12 amps, run 4 amps) considerable energy savings are achieved.
Okay, the first part of this sentence is true … starting up a refrigerator does use more power. And, there have been many energy saving gadgets that were marketed on this basis.
For example, there is the PowerPlanner from EnergySmart. Michael Bluejay has this to say about that gadget:
After 100 hours each with and without, the fridge actually used 9.6% more electricity when the device was installed. Looking at just how many watts the fridge is pulling when the compressor is running, the device dropped the load from 195 watts to 189 — about a 3% reduction. Apparently the compressor had to run longer, which is why I used more electricity overall. Even if the compressor doesn’t run longer, a 3% savings on a modern fridge would be about 15 kWh a year — or $1.50. The device itself cost $30. …. Like most magic “plug-it-in-and-save” devices, this product seems like more hype than benefit.
But it’s worse than not just saving any energy, the CPSC has issued a recall on many of these models for safety issues. Doesn’t particularly surprise me.
Another energy gadget tester, Chuck Wright, also tested the product. What does he have to say about refrigerators, in general, “I have monitored operation of the refrigerator for some period of time, and find that when it starts, it draws about 146 watts, decreasing to a steady state of about 130 watts.” In other words, on the refrigerator he monitors, we are talking about a 10% difference between start up and steady operations … a start up period lasting, writ large, seconds.
Hmmm … claims of the massive energy savings by reducing wasted energy due to reduced start-up cycles make me wonder.
In addition, the more efficient refrigeration cycle leads to a more efficient unit, which then leads to a colder storage area. Consequently, by re-adjusting the thermostat back to its normal temperature settings, there are further substantial energy savings, without compromising food safety and quality.
Well, can’t say that this isn’t true … it makes a certain sense. But, now my suspicions are raised.
Now, this does seem to be ‘too good to be true’. A magic gadget that can slash refrigerator energy use. Considering that, around the world, appliance manufacturers have been pushed (hard, even) for over 20 years to find ever more efficient refrigeration, a wax gadget that can slash requirements like seems a bit of a far leap. But … but … I’m an optimist and can still wishes become reality.
After all, as the Guardian noted,
the £25 gadget significantly reduces the amount of energy used by fridges and freezers, which are estimated to consume about a fifth of all domestic electricity in the UK. If one was fitted to each of the 87 million refrigeration units in Britain, carbon dioxide emissions would fall by more than 2 million tonnes a year.
Lets hope that this is true. A little bit of wax could go a long way …