Hang on to your smartphone

The little computer you carry with you requires a lot of energy to assemble. The production of an iPhone 6, for example, released the equivalent of 178 pounds of carbon dioxide, or about as much as burning nine gallons of gas, according to a 2015 study. Instead of buying a new phone, try to keep yours in working condition for as long as possible. But if you must get rid of yours, recycle it or consider buying a used one.

Leave leaves

Leaves provide shelter for worms, moths and some butterflies, which then become prey for neighborhood birds. They also help nourish and fertilize soil, and you won’t burn fossil fuels by using a lawn mower or leaf blower.

Use a dishwasher, not the sink

Dishwashers have improved over the years: Average models certified by the government’s Energy Star program use 3.5 gallons or less per cycle. Compare that with an efficient kitchen faucet, which pours 1.5 gallons of water per minute, meaning that handwashing for four minutes nearly doubles the water use of a dishwasher. If you don’t have the luxury of owning a dishwasher, try to do the two-bucket method: “When washing dishes by hand, don’t let the water run. Fill one basin with wash water and the other with rinse water.”

Buy fewer clothes

Manufacturers use water and chemicals to dye and finish cotton clothes. Polyesters and nylons aren’t biodegradable. In this age of fast fashion, it’s best to wear your clothes for a long, long time. (Buying secondhand helps, too.)

Consider your online order, from click to carrier

When you’re shopping online, try to buy in bulk to reduce multiple deliveries, which can help cut carbon emissions from delivery trucks. Research your items to avoid having to return them, and always recycle the boxes.

Divest from fossil fuel

Do your retirement funds or other investments include fossil-fuel companies? Divesting has become common in union, city and state pension funds. In a 2018 report published by Arabella Advisors, a philanthropy services firm, 61 pension funds have committed to divestment since 2016, bringing the total to 144. Consider adjusting your retirement fund, and ask if your 401(k) can be fossil-fuel free.

Be mindful of your food waste

A massive amount of energy goes into producing the food we eat, especially meat and dairy. For example, the production of a single hamburger uses the same amount of water as a 90-minute shower. And about 40 percent of food in the United States is thrown away. To limit food waste when you’re hosting a get-together, use this “Guest-imator” to calculate the amount of groceries you’ll need. Also check out the “Waste-Free Kitchen Handbook” for more help on reducing food waste.

Tune your heating system

Most American homes are heated by furnaces or boilers, according to the Energy Department, and poorly maintained systems can burn more oil or natural gas than is necessary. Hire a technician to inspect yours to make sure it’s running efficiently and to cut down on indoor particulate matter. And if you have a boiler system that uses radiators, consider installing an outdoor reset control, which modulates the radiator’s water temperature based on the temperature outside. All of this can even result in direct savings for you: These small actions can knock down a heating bill by up to 10 percent.