Thanks to The Killing many people will be suitably attired for National sweater day. And they will be saving energy and money, writes the Volkskrant.

National sweater day started in Belgium seven years ago and is now a worldwide phenomenon. In the Netherlands it was adopted by the Dutch Climate Association which includes 140 local authorities and one local water authority, the paper writes.
Kyoto
This is how it works: put your sweater on, turn the thermostat down a degree and cut down on CO2 emissions. It’s a DIY version of the Kyoto treatment which came into force in February 2005.
Heating accounts for two thirds of the energy used in Dutch households and accounts for half of the national energy bill. Hospitals, schools and office buildings in particular could do much to save energy.
Double glazing and good insulation are obvious energy saving devices but there is a good case for simply turning down the heat too, the paper writes.
According to most environmental websites, the energy bill of an average Dutch family using 18.000 cubic metres of gas would drop by about 80 Euros a year.
Sweater
The secret is in the outside temperature, the paper quotes TU Delft building physics researcher Kees van der Linden, who says that, paradoxically, winter is not a very good time to save a significant amount of energy. A comfortable 20 degrees with the outside temperature at minus 10 means a 30 degree difference and turning down the thermostat to 19 would save only 3.3 percent of gas. With an outside temperature of plus 10 this would go up to 10 percent.
If people took to wearing a proper sweater around the house the thermostat could easily go down to 17 or 18 degrees. ‘As long as your nose or hands aren’t cold it is perfectly comfortable’, Van der Linden says.
Energy illiterate
The fact remains that people are ‘energy illiterate’. The term was coined by Tilburg professor Dirk Brounen who recently found that 27 percent of people do not even turn down their thermostats at night. In most houses it is more energy effective to turn down the heat considerably at night and reheat in the morning than to maintain an even temperature.
But, the Volkskrant concludes, this percentage also means that a great many people are looking to save energy and are getting to wear those trendy Danish sweaters as well.