Emissions fit for a queen

When your power plant is 2 km from the seat of government and its primary fuel stock is garbage, it better be clean. Take a tour of one of the world's most efficient power plants.

Thu, Oct 15 2009 at 9:48 PM EST

Queen Margrethe II of Denmark with Copenhagen smokestacks. (Photo: Karl Burkart)

Positioned less than a mile from the Queen’s Palace and the Danish Parliament, there is a power plant which performs a miraculous feat. It produces heat and electricity for more than 1/5 of the municipalities’ residents using the least sexy of all renewable resources – garbage.

The Amagerforbraending is owned and operated by five municipalities (two of which are in Copenhagen) consisting of 560,000 residents. The plant provides electricity and heat (via an underground district heating system) to 140,000 of those residents whose garbage has become the principle source of their energy.

When I first heard about the cogeneration/garbage disposal system pioneered here in Denmark, I was concerned that it might somehow encourage poor disposal practices. But according to Esben Norrbom who works for the plant, the Danes are very thorough when it comes to recycling.

About 63 percent of waste is curb-side recycled in Copenhagen and 28 percent is garbage. An additional 10 percent is taken to drop-off centers (72 percent of which is recycled, 3 percent handled as chemical/oil waste, leaving 25 percent for the power plant). Last year they burned a total of 485,000 tons of garbage.

The resulting pile of ash (called slag) is used primarily for asphalt and concrete used for the city’s road projects. Here's a walk-through of the remarkable facility:

Denmark has 30 such plants and though Amagerforbraending is 40 years old it is still a leading case-study in clean energy production. The plant has incorporated new technologies like propane pre-heaters which dramatically increase the speed of combustion, resulting in a higher energy output and a cleaner burn.

The plant also scrubs its emissions using limestone and charcoal filters, which are treated to make them ph neutral prior to disposal in a deep mine in Sweden.

Esben pointed out the proximity of the plant just across a small channel from the Queen of Denmark’s palace. He says it is an ever-present reminder that the plant which runs 24-7 has to have ultra-clean emissions.

It is also in plain view of the Parliament and quite close to the location of the COP15 climate talks, so everyone working at the plant is keenly aware that Amagerforbraending has in some ways become a symbol of how to cleanly power a city while essentially eliminating the need for landfills.