The old 50W GU10 bulbs are the work of the devil! People were seduced by their trendyness but probably didn't realise how much they would cost to run. Let's replace them all:)
This whole "equivalence" thing is very confusing. I don't think it has any properly defined meaning, so people can just say what they want.
I haven't checked the original source (I lost the will to live after searching a couple of EU documents), but some LED vendors are saying that this has been tightened up with the ErP (Energy related Products) legislation that came into force on 1st September 2013.
So now there are "useful lumens", as opposed to any old lumens. And useful lumens have to deliver light where you want it, rather than where you don't. And even if they are still called "lumens" in the product description, they must by law be useful lumens. So you may now compare your halogen lumens with your LED lumens, and not be disappointed when purchasing a replacement product. Probably.
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So now there are "useful lumens", as opposed to any old lumens. And useful lumens have to deliver light where you want it, rather than where you don't. And even if they are still called "lumens" in the product description, they must by law be useful lumens. So you may now compare your halogen lumens with your LED lumens, and not be disappointed when purchasing a replacement product. Probably.