I'm wondering whether anyone can explain why the BV10 40 and BV10 46 are rated so differently for energy consumption on the Australian energy rating scheme - 2 stars and 4.5 stars respectively. Why is the larger model more efficient? I must say I was disappointed to see a 2 star label inside the box of my BV10 40 - I thought it might be because of the speaker system incorporated into the television, but this isn't borne out by the 46 inch model's rating.

http://www.energyrating.gov.au/appsearch/tv_srch.asp?sort=[SRI]+DESC&list=basic&type=&Inst=&Inst2=&out=&brand=Bang+%26+Olufsen&B1=SEARCH&Elec=17&Uses=10&Years=10&B2=Recalculate+Costs

Curious...

B&O specifies the (typical) power consumption for these as 147W for the 46" and 193W for the 40".

This is indeed quite surprising and the difference must be due to the actual panel. The specified luminance is the same for both so the larger screen actually emits 30% more light in total. The backlighting technology in the 46" must be a lot more efficient.

I'm not familiar with your star rating system, but it probably factors in the size of the screen, so the 40" may get punished more than just the power consumption difference would make you expect.

Maybe its the LED backlight ?

The 10-40 is lit from all 4 sides/edges as I understand it, whereas the 10-46 is only lit from two of the edges/sides

Therefore half the consumption in that area ?