The Summer Olympics. An opportunity to kick back from the comfort of your couch every four years and watch the world’s most elite athletes go for the gold. Of course, we at the Alliance to Save Energy been watching plenty ourselves -- how about our gravity-defying gold-medal winning gymnastics team, and Michael Phelps and Katie Ledecky’s continued dominance in the pool? -- but being efficiency nerds, we really wanted to know in what ways energy efficiency was being implemented at this year’s Olympics.

We were happy to find that energy efficiency can be found throughout the operations of the 2016 Olympics in Rio de Janeiro -- in fact, the word “efficient” was used 20 times in the Sustainability Management Plan set out by the 2016 Olympics organizing committee, signalling organizers’ understanding of the strong environmental benefits that efficiency can deliver.

But the benefits are more than just environmental -- hundreds of thousands of dollars have been saved through energy efficiency measures so far, and the efficiency savings will continue in the years to come. Here are some of our favorite efficiency initiatives at the Games this year:

1. Lighting efficiency

Thanks to official Olympic sponsor General Electric, Rio will inherit more efficient public space lighting, including more than 1,600 connected LED lights in Flamengo Park and Lapa. The lights use dimming schedules and will use 50 percent less energy, saving the city money that can be re-invested elsewhere.

In addition, the headquarters of the Rio 2016 Olympic and Paralympic Games Organizing Committee adopted new energy-efficient LED lighting technology in a move that will save Rio $500,000 on energy bills over the course of four years.

2. Increased public transportation

In preparation for the Games, the city built an additional metro line, which connects downtown Rio to the western portion of the city where several Olympic events are taking place. The city, which has the goal of reducing transportation-related greenhouse gas emissions by 20 percent by 2020, estimates that the new metro line will offset 55,449 tonnes of greenhouse gas emissions per year between now and 2040.

3. Energy-efficient food packaging

In its effort to help mitigate the carbon footprint of the Games, Alliance Associate and Official Olympic Partner Dow Chemical has developed a sustainable food packaging technology known as “microfoaming”, which minimizes manufacturers’ greenhouse gas emissions by reducing the weight of plastic films and packages. Lighter packaging means more efficient production and transportation of food.

4. Agricultural efficiency

As part of its efforts to reduce carbon output associated with the Games this year, Dow Chemical has also been working with Brazilian farmers from the state of Mato Grosso in implementing the use of energy-efficient technologies in the agricultural sector. The program, which has been implemented across Brazil and Latin America, saves farmers money and energy in their daily operations.

Energy efficiency on the podium

This summer’s Games are off to an incredible start. While the athletes continue to provide drama and perform at the highest level, energy efficiency implementation is saving energy and costs during the competition, and will continue to impact the city of Rio de Janeiro for years to come. Our verdict: this year’s Games will win a silver medal for their energy efficiency efforts. We hope that Olympic organizers in future years will build on this year’s efforts to create an even more energy-efficient competition. Your turn in four years, Tokyo!