VOA常速英语:改进街道照明可以减少碳排放

Our increasingly industrialized world needs huge amounts of electrical energy,but our power plants still rely mostly on technology introduced as early as the 19th century - coal-powered plants, hydroelectric dams or somewhat newer nuclear energy, all of which have their own shortcomings.

Renewable sources, such as solar plants and wind turbines, have just started making inroads in lowering harmful emissions, while safer fusion-based nuclear plants are believed to be many decades off.

But scientists say we can slow down global warming by lowering energy demands for street lights.

These common features of the world’s urban areas require a lot of electricity.

The U.S. Energy Information Administration estimates that in 2012,lighting for buildings, streets and highways in the U.S. used about 274 billion kilowatt hours.

In a bid to make Copenhagen the world’s first carbon-neutral city by 2025, scientists in the Danish capital are testing a variety of new street lighting technologies.

Kim Brostrom is the chief technical officer of the Danish Outdoor Lighting Lab.

“We have installed nine kilometers of streets, we have 280 masts placed here, we have 50 different solutions, we have 10 different management systems, and we have a lot of different sensors and things out in the open area."

Chief science officer Jakob Andersen says the lights can be managed individually from a tablet computer or a smart phone.

“You can monitor the run time, the efficacy, the lumen output or the power consumption, and then we do real time measurements on the lux levels on the street level."

The main goal is to lower energy consumption when the light is not needed. So the lamp brightens up only when it senses an approaching pedestrian, cyclist or vehicle.Some of them even have a backup wind generator or a solar cell.

Scientists say installing the smart lights city-wide could save up to 85 percent of the current budget for illuminating the Copenhagen streets.