Sometimes, MacBooks have issues that cause them to think that they are not getting any power. Of course, the biggest symptom of this issue is that you try to wake up or turn on your MacBook and you get nothing but a black screen. Nothing at all. 

If your MacBook has one of the MagSafe power adapters that lights up to indicate charging status {red= less than 10% charge (leave plugged until it at least changes to amber), amber=charging, green=fully charged} look to see what it indicates. If the cord is not lighting up, you may have a bad power adapter or you may be plugged in to an outlet that is not getting power. Try another outlet and see if that changes things.

Generally, the MacBook will not power up or come out of deep sleep mode until you have reached a certain minimum charge. Wait until light is amber and then try pressing power.

If the light is green and the computer will still not turn on, then you may need to reset the computer's System Management Controller (SMC). On Macs with non-removable batteries (most of them these days), this is accomplished with a simple three key, one button hold:

1 Plug in the power cord.

2 Press Shift-Control-Option (hold them all at once - we call this a 3 finger salute), then press Power button.

3 Hold all of these keys and the power button for about 10 seconds. (it may actually help to count "1 Mississippi, 2 Mississippi, etc")

4 Release all of them.

5 Press Power as you would normally start your Mac.

We find that many times that is all it takes to get the machine working. 

If none of the above fixes work, please fill submit a ticket.