Systemlösningar för plus- eller passivhus
En studie med syftet att lösa energibehovet för ett specifikt hus.
The purpose of the house which is the basis of this report is to be able present itself on the market as a relatively cheap and at the same time a climate friendly choice. The house is supposed to be able to be built anywhere in Sweden and the rest of Scandinavia in a short period of time. This puts demand on what kind of heating system the house can have, since not all places have the geographic advantage of being able to use geothermal or district heating. Therefore the heating system choices will only include those that are not limited by their geographic location. The house will be built in modules which only require the groundwork to be done before the house can be erected. In this report "System solutions for plus or passive-housing" a comprehensive literature search has been conducted as well as a number of calculations. This has been done to find out which system solution would be most appropriate for this specific house. After calculations and literature searches, three different systems was chosen;Water-jacketed wood stove with solar panelsWater-jacketed pellet stove with solar panelsAir/water heat pump with solar panels The results showed economic differences. The wood stove proved to be the cheapest, it does, however release some toxic gases during its incomplete material incineration and it also requires more of the user?s attention. The investment cost of the pellet stove is higher and the fuel cost proved to be around twice the amount, which led to a higher cost in total. The advantages of the pellet stove is that it is a self-feeding system which requires less of the user?s time and attention. It is also a more efficient machine and therefor emits less toxic gases. The heat pump proved to be the most expensive choice and also the more difficult choice to assess as to its environmental impact. This due to the fact that it uses electricity as fuel. This electricity is hard to predict the source of. If the source is renewable it could be argued that the heat pump is the most environmental positive choice. If the source on the other hand is from coal or oil plants this will release large amounts of greenhouse gases into the atmosphere. The obvious positive aspect of the heating pump is its ability to run without the help of the user. Something that both the pellet and wood stoves need. The house proved a few flaws in the thermal bridges that appear in the joints of the house. This could be solved by providing these joints with extra insulation which are otherwise only made of wood. The conclusion is that this is well thought-out house which pass the definition of a passive house in most places in Sweden. It did now, however, pass the definition of a plus house. This due to the angle of the roof which led to a lesser amount of solar cells, which could not generate the amount of electricity needed to sell more electricity then what is needed to purchase. This is the only part of the house that can be seen as a truly big flaw, since this goes against the purpose of the house. The type of heating system has not been made as a definite conclusion, but is being left open for reader to decide. According to the last calculations made however, the wood stove proved the best choice, this is due to its cheap price over a long period of time. Something that does not prove decisive for all.