One of EU´s biggest goals in climate policy is that carbon emissions shall be reduced by 20% before 2020 to inhibit global warming. By combining renewable energy sources with a more efficient energy system, it could go faster to achieve these goals.

The purpose of this report is to find out if it is possible to construct a self-sufficient house, located in Karlstad, which uses solar and wind power for its energy demand. The house should not be dependent on the district electricity, but should be able to provide its own energy demand, by being equipped with an energy storage system. To reach the goals of the report an examination of the energy demand for an energy efficient house was made. This was done by comparing the house with a passive house. These calculations were simulated in the program VIP-Energy. The calculations of the solar and wind power were based on the energy demand of the house, and it was supplemented with a pellet stove and battery in order to make it self-sufficient. During the report, an investigation has been made as to the environmental impact of the house compared to an equivalent house that is heated by electricity. An economic analysis has also been calculated for the house.

The project led to a passive house with a total energy requirement of 11.906 kWh per year. The process required a number of assumptions which may have given rise to some uncertainty in the results. In order to provide the energy need for the house a solar panel system with a maximum power of 12 kW and a wind turbine of 10 kW was chosen. This resulted in an excessive energy production during the summer months and yielded a large surplus of electricity. The solar and wind power generated a total surplus of 18.000 kWh per year. The surplus generated was a consequence of the house intending to be self-sufficient, therefore the calculations was made during the time of year when energy demand was greatest. The system was finally outfitted with a pellet stove and seven sections of 24V batteries with 250Ah/battery.

The cost analysis estimated an initial cost of solar panels, wind turbine, pellet stove and the batteries. The initial cost was estimated to 403 500 kr and a pellet consumption of about 1000 kr per year. It would take a minimum of 25 years to repay the initial cost if the house was compared to an equivalent house that uses electricity for its energy demand. The amount of carbon dioxide emissions that is prevented compared to an electrically heated house is almost 1000 kg per year. This is equal to 266 one-way trips during a 25 year period between Gothenburg and Stockholm with a mid-sized car.

Conclusions to be drawn from the report are that it would not be economically sustainable to construct a self-sufficient house. Since the house is not connected to the district electricity, it cannot sell the surplus electricity during the summer months. However, further studies could be done to determine the opportunities for the house to be fitted with a charging station for electric cars. In this way the house would be able to provide the intrinsic means of transport that does not give any effect on the climate. That could also save the cost of other fuels for transportation.