For more accurate calculations should also take into account the door, skeletal structures, such as timber transfer coefficient is 2.2 for a thickness of 250mm. Heat loss also occurs through the substrate, one can assume that the lowest temperature in the greenhouse soil is 7 degrees and the transfer coefficient for the soil is 1.7 degree which gives us a sample project in addition to 20 x 1.7 x 7 = 238 W. The total the small rounded need heating power 10 KW. An additional factor in the ventilation heat loss is to be included, depending on the type of heating. Heating may be inching from an existing heating system in your home or use a separate installation, which will be allocated only to the greenhouse. Using a boiler in which combustion occurs should also take into account the combustion. In the case of an electric boiler is not needed.
Type of Heating
Water Heating. Hot water passes through the heating pipes or radiators, thus heating the air gives off heat. The energy brought into the greenhouse must be constantly replenished. Water is heated by the boiler for solid fuel, oil or electricity. Heating is easy to use and can be completely automated by connecting the temperature sensors.
Heating air. This method consists of introducing a greenhouse heated air tight. The advantage of this solution is good air circulation, heating rate and the fact that they do not need additional heating elements inside the greenhouse. Disadvantages of a quick losing temperatures while blowing does not work, and air drying. Hot air heating is inefficient because they are used in small greenhouses.
Heating shock. Heating by electric convector heaters or oil is expensive to operate but does not entail additional investment and, for the heaters in the summer may be coming from the greenhouse. Using heating cables is difficult to heat the entire greenhouse, rather they are used to heat the soil in the beds of small and greenhouses.
Gas heating. Gas heating appliances are not suitable for the greenhouse. They may apply only in plastic tents and greenhouses for reheating for a stronger rescue periodic frosts or plants against frost in spring and autumn. Another restriction is that you should not use gas heating in rooms below ground level because of the risk of explosion.
Heating furnace. Hardly a convenient solution for this reason that requires constant supervision and policing of fire sometimes at night when frosts are greatest.
Heating Duct. Such heating only pays to build a small greenhouse, because of the low cost of construction and low operating costs. Unfortunately, it requires constant heating time-consuming supervision. The furnace can be powered by waste from the garden.