A powdered version of alcohol (known as Palcohol in its commercial version, I believe) has been approved for sale in the US. It's also been subsequently banned from multiple states for the "inherent dangers" that it possesses, aka people who know nothing about the science of the substance think people will be using it to:
1) get drunk faster
2) spike other people's drinks
3) snort it (but why?)
And so the guys at WIRED decided to do an expose of whether or not these concerns are valid.
Bottom line: they're not. You can check out the full examination here, but that's what it comes down to.
Each 'shot' of powder is just too much powder for anyone one person to reasonably consume. They could probably get the efficiency up from 55% percent, but even if they were able to somehow turn alcohol into powder with no additional ingredients and 100% concentration, it would still be about 10g of powder per shot. Which is way too much.
Not only that, but also, powdered alcohol really doesn't seem to be effective at all for the purpose of enjoyable drinking, or anything like that....so I'll just stick to the real stuff.