Friday, 23 June 2017

More energy label confusion coming

Under the EU energy label scheme appliances were originally labelled A-G with A as the best. Then as standards improved new grades were introduced: A+, A++ and for some products we now have A+++; apparently this is confusing. So the EU is updating the scheme with a rescaling so everything goes back to A-G: they say this is simpler. However, during the changeover period we will see two kinds of labels which is going to be even more confusing. Fortunately for most products there is other information on the label that you can use to compare products by actual energy consumption. Unfortunately this is not so for heaters, which only show the energy class and even this means different things for different types of heater.

Obviously, it takes time to introduce new labels. For most products the old system and the new system will coexist between 2017 and 2021. For heating products like gas boilers, the old scheme will continue to overlap with the new until 2030 [2]. So if you see an A rating on a new boiler, this could be really good (in the new scheme) or pathetic (in the current scheme).

The EU has recognised that there will be further improvements in efficiency, so they have come up with a methodology for repeated rescales. Once all A+ labels have disappeared from the market, further rescaling will be triggered by a surplus in the top classes, namely 30 % in class A or 50% in class A+B. At the time of rescaling the top two classes are to be left empty, aiming for a 10 year validity period of the label [1].

That means after a rescale all the old A grade products become C or less, presumably with an overlap period where you will see new scales on some products and old scales on others. More scope for confusion. If there is 10 years between rescales and each rescale takes 4 years that means we are confused for 4 years out of 10. Under this supposedly simple new scheme, the letter rating on an energy certificate is practically meaningless nearly half the time.

For most products the energy label give more information than just the energy class. For example for fridges and freezers you are shown the estimated annual energy consumption; for washing machines you get energy use per wash. This means you have an actual number (in kWh) to compare between products. However, for heating products the only information on the label is the energy class and a noise level (in db).

To cap it all, the current labelling scheme for heaters is already confusing because there are different scales for different kinds of heaters. Consider space heaters such as gas boilers or electric heat pumps. Here an A class means a seasonal average efficiency between 90 and 98% for boilers and most heat pumps but 115% to 123% for 'low temperature heat pumps' (usually designed for underfloor heating with a delivery temperature of around 35C).

Wouldn't it be easier if we just used a fixed number scale for all products?  This number could indicate energy use so in all cases small numbers are good and large ones are bad. For fridges and freezers it would be annual energy consumption; for space heaters it could also be annual energy consumption for reference heating demand (i.e. reference heating demand/seasonal average efficiency). The numbers we see on different products will be different but this does not matter because there is no need to compare them. It makes no sense to compare a boiler with a fridge or a washing machine. There will be no need for rescaling, ever. All you need to remember is that small numbers are good. What could be simpler?

[1] Update - Clearer energy labelling: improved energy efficiency (EU Council) March 2017
[2] Long freeze on new labels for heaters may slow innovation, decarbonisation (Euractiv) June 2017
[3] EU regulations for rating heaters (space heaters, combination heaters, packages of space heater, temperature control and solar device and packages of combination heater, temperature control and solar device) ( 2013

1 comment:

  1. The problem with using real numbers is that few people know if '0.3' '7', '82', or '650' is 'good'. What counts as 'low'? Unless you scale everything to be in range 0-10 or 0-100. Numbers make comparisons easy, but if one is '7' and the other '8', does that make them almost identical or one loads better the other. You have to know how long the scale is to make a useful comparison.

    At least with A-G you can assume that 'A' is good (although it's not entirely true for fridges as they got so much better than the old 'good', so 'A' is more like 'not bad'), so it mostly works well enough even with ignorant consumers.

    It does turn out to be harder to do well than you might think.


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