How much power does any piece of a city block use? There’s no way to tell. A building’s facade, unless it’s covered with lights, isn’t exactly screaming its annual energy expenditures.

A new map by the School of Engineering and Applied Science at Columbia University gives us a picture of energy consumption in the five boroughs of New York, on a block-by-block basis. It’s kind of like Google Maps for spotting the greediest energy hogs of the city (and it won’t surprise you that Manhattan is, by far, the biggest spender). You can zoom all the way down to your own building, if you’re so inclined, and see how your building stacks up.

Interestingly enough, the project isn’t just an example in smart data mapping; it’s an example of smart data extrapolation. The specific information on this map is actually a series of estimations.

“What we first estimated is how much energy is used per square foot of the building on average for a specific class of buildings in New York City,” Vijay Modi, professor of mechanical engineering, explains to Co.Design. “Once we estimated this, we applied this estimate to each building in order to determine the estimated use by each building.”

The team was working with only one source of hard data: the total amount of energy (electricity, natural gas, fuel oil, and steam consumption) sucked by zip code. As that wouldn’t be enough to zoom in building by building, the team applied another, homemade filter of data to determine specific energy use by building type. Hospitals use more energy than stores, which both use more energy than residential buildings. And a store with residences on top is somewhere in between. (The filter does not account for varying building-by-building efficiency standards, like LEED.)

The result is a map that, while not 100% accurate, gives us a reasonable snapshot of energy usage across NYC. But wait–we got an idea! How fantastic would it be if the streets were peppered with the steam energy of hot dog vendors?