We are heading towards a huge switch of how energy is produced with fossil fuels being replaced by renewable energy sources. It is not difficult to replace the energy you use in the house and there is no need for futuristic technology. There are already many established products on the market such as high efficiency vacuum solar collectors, heat pumps & small wind power stations that can supply the energy being used in a house.
The company Sol & Energiteknik SE AB in Huskvarna has many different products which can reduce the need for an outside energy distributor. An average house in Sweden uses 15 000 kWh for heating, 5000 kWh for tap water and 5000 kWh for electricity. These figures are based on each household using 14 000 kWh for heating, 5000 kWh for tap water and 8100 kWh for electricity. A wood furnace delivers the heat and the electricity is bought from the electricity company Fortum. Before you decide to change how you heat your house or the way you get your electricity, you need to calibrate the dimension of your system. You should make your house more energy efficient and buy products that run on less electricity than your old ones.
By replacing the way of heating the tap water with 5 modules of Intelli-Heat vacuum pipes with the total area of 11,4 m2 which are orientated in a south direction with an angle of 90 degrees, you get 6200 kWh hot tap water from March to November. The demand for heating is covered with the heat pump - NIBE Fighter 1135; 6 kW. From 3600 kWh of electricity and a COP of 3 you get 11 000 kWh of hot water. All the heat is stored in a 2000 litres accumulator tank which should store the heat for three days depending on the outdoor temperature.
The electricity in the house is produced by a wind power station from Hannevind AB. An 11 kW plant can produce 20 000 kWh electricity when the wind speed is 6 m/s. At locations where the wind speed is lower than 6 m/s, the plant of course will produce less electricity. In Jönköping, where the average wind speed is 4,2 m/s, a plant like this will produce 6900 kWh/year. To compensate the lower energy production in the summer, when the wind speed is lower, you can rig up 10 m2 of photovoltaic panels. They produce about 1000 kWh electricity per year and are simply connected to the grid through a wall socket.
The grid will be used as a backup, which means, when you got shortage of electricity you buy it from the electricity company which owns the grid. When there is too much electricity you send it out on the grid so others can use the electricity.
The cost of a system like this will range from 200 000 to 460 000 Swedish crowns depending on where in Sweden you live. You have to adapt your system to where you live, if you for example live on a very windy location you may focus on the wind power station and maybe give up the heat pump. An annual cost of 33 000 Swedish crowns plus the cost of the electricity you have to buy from the electricity company, is quite expensive but you should keep in mind that the energy is as good as free when everything is paid after 15-20 years.
In locations where the wind speed is insufficient (be...
