Electricity gives us light, warmth and many of the conveniences of modern life. It powers industry, our homes, our schools and our offices, yet most of us take it for granted. Do you know where your electricity comes from or how it reaches you to provide the energy you depend on? It's Grid Week, and the Department of Energy's Understanding the Grid infographic gives a bite-size education on how electricity is generated, transmitted and distributed to our homes and businesses.

Is it time to replace your old dryer? Great news: The federal Energy Star program has started certifying clothes dryers, making it easy to pick out the most cost-effective and efficient models. Read on to find out what the change means and how to pick out the best model for your home.

Moisture and Heat Settings

The upside is clear: “ENERGY STAR certified dryers use 20 percent less energy than conventional models without sacrificing features or performance,” the program promises. So what took so long for dryers to get the federal efficiency stamp of approval?

“With dryers there are fewer major variables to manipulate — mostly it’s drying time and the amount of heat provided,” said Emilio Gonzalez, a Consumer Reports test engineer, so it was harder to find adjustments to meet the standard.

How did manufacturers finally find the extra energy savings?

The savings are not trivial. Energy Star claims that if every household in America switched over, consumers would save a total of $1.5 billion annually in utilities. The reduction in pollution would be the same as taking 2 million cars off the road.

Upgrade the Laundry Room

The first certified models are already available -- find a list of them on the Energy Star directory, which allows you to compare size, fuel type, energy use and other factors.

If you have a gas hookup in your laundry room, consider purchasing a gas-powered dryer. These models have a higher price tag but are more efficient across the board than their electric cousins. No matter what kind of dryer you buy, make sure you adhere to the following tips so you get the most for your money: