I'd like to discuss some results of my research on energy efficiency of deepcoin mining.
This is the example of my small miner based on three Radeon cards: 7950+7870XT+7750.
The power consumption was measured for the whole system.
There are more than one result for some algos as I wanted to test different settings.
Scrypt is just for a comparison and settings are not really optimal. Sorry, I wouldn't bother much with searching optimal GPU settings for scrypt any more.



My general conclusion is that:
1. deepcoin algo can be really efficient and eco friendly
2. however it is also very settings-sensitive algo and can turn in power greedy if you don't care for that.

If you press these settings for maximal performance you may get in result significant electrical waste.
In this case tiny performance improvement of roughly 8,5% is completely not worth of 27% power drown increasement.