Building owners and facility manager are constantly challenged to achieve energy efficiency by reducing costs, while ensuring tenant comfort and compliance through the use of energy management solutions. Energy management analytics companies have been working continuously to support these initiatives by capturing, aggregating and normalizing data from all areas affecting building performance, including building automation systems, IoT devices, sensors and weather. Gathering all of this data is no easy task but by doing this, an incredible opportunity is created for identifying energy efficiency. This compilation of information is often referred to as a data lake, because so much information is assembled and by digging deep, you never what you can find. Joking aside, creating a data lake, aka data warehouse where all of this information can be stored, is the first step to applying energy analytics to drive energy efficiency.