Why is SQL Server 2014 consuming so much RAM with no active data stored?
First thing is to change the max memory setting on your instance using either the GUI or sp_configure.

EXEC sp_configure 'max server memory (MB)', 1024


Then go into SQL Server Configuration Manager and stop and re-start the instance.  You don't actually have to restart your laptop.

That will fix it so that your instance won't use much more than 1gb.  I'm fairly sure it uses memory that isn't included in this setting but not a huge amount.  

SQL Server likes to take memory for what it needs.  It isn't so good at giving it back so it's a good idea to keep the max memory setting on your personal laptop fairly low unless you happen to need more.  I use the 1gb setting for random small queries etc and if I need more I update it.  Of course my laptop only has 6gb of ram total.