Several weeks ago, my daughter came home and said “Dad, why does Norway have to import trash to keep its power plants running?  You should write a column on that.” And so I have.

First, in the interest of full disclosure, I love Norway. I have been there both for business and pleasure and in my opinion it is the most beautiful country I have ever seen. And I have seen quite a few.

Norway is the 6th wealthiest country on Earth, with a per capita GDP of approximately $64,000 per year. It is always near the top of any lists which rank things such as livability or happiness. While there are a number of factors which drive Norway’s wealth and high quality of life, an abundance of cheap energy is certainly among the most important.

Until the 1960s, Norway was consigned to being a quiet nation on the edge of Europe known primarily for fjords and fishing. Then oil was discovered in Norway’s portion of the North Sea – a lot of it. Like any good socialist country, Norway created a state-owned company to extract the oil and reinvested the profits in infrastructure and education. As a consequence, everything in Norway is nice – the hospitals, the roads, the schools, the railroad stations, the trash cans, even the people – all nice.

They also used the proceeds from the North Sea oil fields to build dams and hydroelectric power plants. If you are not familiar with the weather and terrain of Norway, it’s as though it was designed by Odin to show us where hydroelectric power plants should be built. There are an almost infinite number of deep, narrow river valleys(1) and it is almost always raining. As a result, Norway generates over 98% of its electricity from hydroelectric power.

The abundance of cheap electricity has motivated the Norwegians to consume it at rather extravagant rates. The most obvious example that I observed during my visit was the thousands of miles of street lights that illuminate even the rural highways of Norway every night. Norway also exports electricity to neighboring Denmark and Sweden. With a consumption of 27 megawatt-hours per person per year, Norway’s electricity use is three times the European Union average.

With this background on Norway in mind, let’s return to my daughter’s question. Why would a country which is awash in oil and hydroelectric power be importing trash to burn?

Let’s begin our answer by asking why anyone would want to burn trash. Homes and offices generate quite a bit of waste, including paper, plastic, food, and objects made of or containing metal. From a conservation of energy stand point, the most efficient way to handle this waste stream is by following the familiar mantra of “reduce, reuse, recycle.”  However, even if a municipality takes Carrboro-esque efforts to minimize waste, there is always some left over. This leaves two choices: land fill it or burn it.

Land filling is a problematic solution.(2) It takes up space, which Norway does not have a lot of, it smells, and when organic material decomposes in the low-oxygen environment of a land fill, methane, a potent greenhouse gas, is produced and emitted.(3)

Many European countries, Norway in particular, are trying to limit land filling, so instead they are burning their trash in high-tech incinerators. The heat generated from burning the trash is used to make steam. The steam can be used to spin a turbine to make electricity(4) or can be used directly to heat buildings. You can also use the steam to do a little of both, which is called cogeneration.(5) Since Norway already has an excess of electricity, they use the energy from burning trash to heat buildings.

Since Norway has become accustomed to having plenty of money, they built impressively large and expensive incinerators which can burn a lot more garbage than the trash-minimizing Norwegian populace can generate. This excess incineration capacity, coupled with the fact that it is often cold in Norway, requiring a lot of heat generation, explains why barges of garbage from other countries head to Oslo.

As other European countries also try to shift from land filling to trash burning, they have two choices. They can invest hundreds of millions of dollars to build their own incinerators, or they can pay Norway to burn their garbage for them. Since it’s hard for politicians to get their constituents excited about spending a lot of money on an expensive incinerator, the option of paying a fee to Norway to burn it for them is attractive. Therefore, back in Norway, the residents now enjoy free heat.

Unfortunately, burning trash is a rather problematic enterprise. If you were to try to design an ideal fuel, it would combust completely and generate only carbon dioxide and water vapor as gaseous emissions, and leave behind no ash. Chemically speaking, a fuel such as this would be comprised of only carbon and hydrogen atoms. As luck would have it, Mother Nature has provided such a fuel: natural gas. It is due to these qualities that natural gas is touted as “clean burning.”

As soon as a fuel contains atoms other than carbon and hydrogen, such as sulfur, or nitrogen, or mercury, or iron, things get complicated. When you burn a fuel which contains these atoms, for example coal, you generate problematic gas emissions such as sulfur dioxide, which need to be scrubbed from the emissions to avoid creating acid rain. Further, since you now have less than 100% combustion of the fuel, you create ash which will contain all of the often-toxic metals which came in with the fuel. This is why power companies like Duke Energy end up with mountains of toxic coal ash.

Trash, being full of trash, is by no means an ideal fuel. The Norwegians do a pretty good job of minimizing the attendant problems by sorting the trash before it goes to the incinerator to remove metals and plastics, in an attempt to burn mostly paper and wood.  However, it is not practical to sort through the trash that comes in from other countries on the barges. Therefore, the Norwegians have to depend on the people in the source nations to do this job. Currently, the Norwegians regulate the importation of trash by using a long-standing system of European cultural profiling. They import trash from the “advanced” northern European countries such as England and Ireland, but will not accept shipments of trash from southern European countries like Greece, Italy, or Spain. Some things never change.

While there is a place for trash burning in our solid waste management system, overuse of this approach can be a problem. Reusing and recycling trash, whenever possible, is far, far better than burning it. Unfortunately, since sorting all of this trash can be a pain, the availability of cheap incineration capacity can be seductive and lead even the Norwegians to burn things that they should not.

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1. If you are going to dam a river to make hydropower, you want to spend as little money as possible building the dam, but still want the resulting lake to be very deep. Therefore, a narrow, deep valley, like a fjord, is much better than a wide shallow valley.

2. Local residents who have spent the last several decades dealing with the issues and challenges with the landfill along Rogers Road know this quite well.

3. Methane generated from landfills can be and sometimes is captured as a fuel, which helps to mitigate this problem. I was tempted to elaborate on that point, but this column was already long enough.

4. To understand how spinning turbines are used to generate electricity, please read my previous column Electricity Production 101.

5. The coal plant at UNC is a co-generation facility.