LAKEWOOD, Colo. -- When the Christmas lights go up, so does your energy bill.

This year, light-emitting diodes or LEDs are the must-have item.

"More people are asking about them to save energy and money," said Ben Ramirez, master electrician at the Lakewood Home Depot.

LED technology only uses a fraction of the electricity of standard incandescent bulbs. Ramirez said they'll save you 80-90 percent off your monthly energy bill.

Since LEDs use less power, you can string more of them together. If you buy a strand with 50 lights, you can plug more than 40 of them end-to-end using just one outlet.

Lakewood resident Crystal Medina said she bought LED lights for her Christmas tree because they don't get hot, making them safer for her young son.

"I just want to make sure it's safe for him. He can't hurt himself and be able to eat it, burn his hand," she said.

The average life span of LEDs is also much longer than regular bulbs. Most LED lights will last 20 to 25 years before needing to be replaced.

Home Depot said the biggest question customers have is the upfront cost. Most LED strands cost $5-10.

"People that understand the savings, they do go ahead and spend a little extra," Ramirez said.

7NEWS made the switch to LED lights for its Christmas decorations two years ago. LEDs will also cover the Denver City-County building for the first time this year, saving the city $180,000 a year.

The city also plans to leave the lights up year-round to save the cost of removing and installation.