In June 2009 MetLife Stadium signed a Memorandum of Understanding (MOU) with the U.S. Environmental Protection Agency, with the intention of improving the facility’s environmental sustainability and becoming a steward of green operation. The EPA released its annual assessment of the stadium’s progress toward that goal this week, and the data showcases significant gains at the home of the New York Giants and New York Jets.

The analysis shows that MetLife Stadium has reduced its carbon footprint by the equivalent of over 234,000 metric tons of carbon dioxide, saving the facility nearly $20 million in operating costs in just under four years of action. The reductions are equivalent to the annual emission of over 48,000 vehicles or the annual energy use in more than 12,000 homes.

These gains were largely the result of several initiatives put into place at MetLife Stadium. The most recognizable step was the installation of a solar-energy ring around the top of the stadium to mitigate the energy usage at the venue, which went online in August 2012. But the biggest gains came from an aggressive energy-conservation program at the stadium that reduced energy use by 20% from the opening baselines.

The EPA also noted the efforts by MetLife Stadium to expand green purchasing decisions, sustainable landscaping, increases in recycling and composting, and water conservation through low-flow installations and waterless urinals. As host of the 2014 Super Bowl, MetLife Stadium has quantitatively shown progress toward its stated mission to host the greenest championship game to date.

Read the full assessment here. [PDF]