The energy used by video game consoles has recently been measured by the Natural Resources Defence Council, a non-profit environmental advocacy group. The results are particularly interesting, and only Nintendo’s Wii U has fared well.

The study found that the consoles from Sony and Microsoft (PS4 and Xbox One) consume much more than their last-generation counterparts – in fact, about 3 times as much – with the Xbox One the most power hungry by far.

The Wii U was found to be the most power efficient console – and not just from this generation. It’s the only console that consumes less than its predecessor, with the original Wii measured at 40, and the Wii U slightly lower at 37 kWh/year.

The numbers are estimates based on console usage and power draw. According to NRDC, video game consoles in the US consume as much electricity in a year as the city of Houston. The electricity cost to run all of the consoles every year is a staggering $1 billion.

Check out the graph below that compares the Wii U with the competition. The Wii U isn’t as powerful as the other consoles, with the hardware specifically designed to fit the power envelope of the system.

Let us know your thoughts on the whole energy comparison below.