It doesn't mean the «energy efficiency» rating is wrongfully stated, the statement is true, regarding electrical efficiency of the device, yet the cold produced by the device is not delivered to your house as you might think. It is split unevenly between your house and the Earth's atmosphere, where less than 1/2 is delivered to you, all the rest surprisingly enough is dumped into the atmosphere, no matter how many «pluses» they print on the energy efficiency label.

Forget about «A++++» — let's do some elementary physics

This beautiful picture is not true. Well, technically it is not entirely untrue, in absolutely dry air this picture is true, for example in Atacama desert or on Mars, but chances are the atmosphere of your house contains plenty of water, which is not mentioned on the picture. When your air conditioner cools air down it cools ALL components, of which the significant part is water vapour. The water vapour concentration is limited by the air temperature, lower the temperature lower is the maximum possible water content. That creates the dew point phenomenon. If you drop the air temperature below a certain level water condenses out, and your air conditioner heat exchanger operates most certainly below the dew point, this is why water comes out from the device. ...And goes straight outdoors carrying the cold produced on your expense to the earth atmosphere. So that the correct scheme should look like this:

Please, stop chanting «A+++++»

Even if we assume 100% efficiency of the device, it simply DISPOSES OF a significant part of its END PRODUCT. Now, let's us estimate how much significant is it.

Let's assume you want to cool a room down to comfortable 24 C, in a hot day (37 c, with 68% humidity, which is a typical July day in my home town).

Thus the air initially contains 0.03 kg of water per m^3.
If we now generously assume that the air pump operates at 11 C then we only need to cool 1/2 of the room volume in order to reach 24 C. It means that the heat exchanger produces 100% humid air at 11 C, which contains 0.01 kg of water per m^3.

Thus, the heat exchanger dumps 0.02 kg of cool water per m^3 of air.
Vaporization heat of water is 2257 kJ/kg, therefore your air conditioner dumps 0.02*2257 = 45.14 kJ/m^3
Let's see how big is this number.

Specific Heat capacity of humid air in our context is about 1.034 kJ/kg/K (with insignificant variation for such a rough calculation) and the density is about 1.2 kg/m^3. Thus the «consumer value» (pardon my language) of the air conditioning is roughly: 1.034*(37-24)*1.2 = 16.13 kJ/m^3

While the actually produced work consists of cooling half of the given amount of air from 37 to 11 C plus condensing water, which amounts to: (1.034*(37-11)*1.2 + 45.14)/2 = 38.7 kJ/m^3

Finally the ratio is: 16.13 / 38.7 = 0.42 — i.e. roughly 58% of the cold produced by your air conditioner goes straight outdoors.

Of course, it is a very rough estimation, but it gives you the order of magnitude of the phenomenon. Although I tried to give a conservative estimation, feel free to directly measure your air conditioner water output in order to get the precise number — I bet it will be even worse than «60%» stated in the title.

This loss does only seem inevitable!

The sad part is that this energy is completely recyclable for no cost — all you need to do is to vaporize this water on the heat exchanger of the condenser unit — BUT NOBODY CARES.

I was confronted with a serious argument against Tesla cars (or electrically powered automobiles in general). It reads thusly: «If you replace all cars with Teslas the power grid will not be able to sustain the resulting tremendous surge of energy consumption». To me it sounds like a legit matter for a quick investigation, so here we go.
Read more →

Today I want to talk about ecology, in a very unorthodox manner, as I always do with any subject. There is one very necessary practice in the metallurgy all over the world: slag dumping. Of course, our cherished environmentalist buzz-makers know nothing about that, because steel and copper, just like coffee and croissants, grow on trees. And it is much better to keep them at their present state of ignorance, as long as we want a serious, intelligent, and productive discussion on the topic.

First of all, there is nothing wrong with the metallurgy in general and the slag in particular. However, there is some room for a significant improvement that benefits our «environment», unlike bullshit «carbon taxes» or «wind turbines». In order to understand the basics of the problem watch any of the «slag dump» videos on youtube, like this one www.youtube.com/watch?v=zKOENNXsSBQ This «molten lava» is slag, an inevitable byproduct of any metallurgical process. It has no use in the industry, it contains no precious components, and it has to be removed from furnaces, in order to keep them running.

The first thing that must strike you as you see the action is: «what a waste of energy!!!» Indeed, slag is hellishly hot, where «hot» means two important properties: abundant and high potential, which makes the energy easily CONVERTIBLE. But, hold on, this shit is solid under normal conditions. When you extract energy from molten slag it will solidify, incapacitating any conceivable heat exchanger.

Let's apply some IT reasoning here. While it is difficult to take energy away, how about taking an energy consumer in? Picture that, you have to heat something, so you mix it into hot slag. The output will very likely to be total garbage… Yes! GARBAGE! Put garbage in, melt it by the heat contained in the slag, and then shape it in building bricks, or fillers, or whatever you need to build artificial islands…

In the end you get a pretty normal solid waste processing plant running on free energy.