IT IS NOW the 24 October and here in Uppsala in Sweden, the frosty nights are coming more often. It is time to begin to fire the wood stove.
The firewood is brought from the outdoors magazine, to the indoors storage. This is about 0,3 m2 and will cover the need for about 14 days when it is as most winter. It has then about 14 days to dry up a bit more from the ca 20% during winter conditions outdoors, to about 15%. This makes it more easy to start the fire and this is very convenient as well as it is contributing to a more efficient burning.
Station Lunda is using about 2-3 m2 of firewood in a season. This should be compared to the average of about 11 m2 for households in Sweden that are mainly heating with firewood, but also has complementary electrical heating. Station Lunda doesn´t use any other direct source for heating than firewood. On Station Lunda, the need for heat is adapted to the outdoor climate. During May-October, there is no heating at all. The temperature is not really regulated other than through the ventilation.
During the winter months november - may, the indoor temperature is adapted to the outdoor temperature. In the beginning of the winter season, the ground and the house has a buffer that holds the temperature indoors much higher than the outdoor temperature. In midwinter this buffer is gone and at the end of the season, in the late spring, there is actually the reversed situation. The ground is now colder than the outdoor temperature, and is cooling the house down... This requires some heating as far as long into the month of May.
Indoors temperature is kept about 15-20 degrees above the average daily temperature during the winter period. When the average temperature is down to 0 degrees, the indoor temperature is about 12-18 degrees at daytime, and lower at nights. Station Lunda is generally setting a minimum temperature to about 9 degrees. It is not efficient to lower the temperature more during nights, as more heat energy is required to get the temperature up during the days. The strategy is that the cooler the outdoor temperature, the lower the indoor temperature.
The norm for indoor temperature today in Sweden is 20 degrees. That is also the temperature level for the tropical zone on Earth. There is no natural reason to keep a Tropical climate in a Temperate climate zone. This strategy is also one of the main reasons for the very high energy consumption by heating in Sweden. If the strategy of adaptation is incorporated there will be both lower energy consumption, lower exhaust emissions from firewood heating, and the humans will get better health because of lower difference between outdoor and indoor climate. The relative humidity is also being kept higher, which is good both for human health as well as for the house. The society benefits from lower energy consumption and thus lower energy production.
Sweden is using about 50 Twh energy for heating. This is abut 5000 kWh per capita and when the average household is 2,3 individuals, it means about 11500 kWh per household. There is also a great dark number here, as only some sources are measurable. The amount heating by electricity is outside these figures, and this can be a lot. Electrical heaters in garage, in outhouses and as backup heating when no one is home... We can assume that the real figures are considerably higher, perhaps several hundred percent higher?
A great deal of the heating energy is used for premises that not benefits from being heated. Care sales offices, with huge glass walls, shopping centers etc. Food Stores are an interesting case, where much of the food must be kept cool and even frozen. Heating these stores, increases the cooling energy and it would be a doubled benefit from lowering the indoor temperature. Visitors to the stores are almost without exception having their outdoor clothes on when they enter the stores, so they dont really need it to be heated at all.
Much of the heating energy used for building is using highly refined energy with high exergi: electricity. It should be questioned how reasonable it is to use electricity for heating as heat has the lowest exergi form of energy. Electricity has high costs in production and distribution. Also solar and windpower are very costly with high impact on the environment.
The situation for energy in a country as Sweden is that there is used more energy than we can produce in a sustainable way. The heating energy is 15-25% (perhaps 50%?) of the total energy usage in the country. This is much, too much.
Should the houses be heated with biofuel it would for example require 5000 miljon liter rapeseed oil. It would take 6,25 million hectares to produce it. That is more than 100% of available agricultural area that is 3 miljon hectares. It would require 100% of the regeneration of Swedish forests to produce heat if everyone heated with firewood.
The District Heating that is so popular in the cities of Sweden is burning rubbish, and to produce the required energy, this "fuel" must be imported. The Swedish Water power produces ca 60 Twh yearly and that would cover the need for heating if 100% was used for this purpose.
The situation is clearly an equation that does not adds up.
If we reduced the total energy usage in Sweden to a tenth of the present usage, and that would not be so hard, the current Water power production would cover ALL needs and we would not need Nuclear power, Solar- and Windpower. Neither would we need fossil fuels and biofuels could be reduced to be used for heating.
It is not only the individual that has been spoiled with overconsumption of energy, it is the Infrastructure by State and Government that inforces the overconsumption. Swedish Authorities as the Public Health Authority (Folkhälsomyndigheten ) and the Swedish Energy Agency (Energimyndigheten) are doing everything to encourage a overconsumption in a situaion which is already highly unsustainable.