Technological evolution, lower costs, and, sometimes, public assistance to reduce investment expenses are combining to make the use of renewable energy sources in the mountains an increasingly attractive proposition.
Many people, especially in the north of Europe, have decided to abandon traditional heating fuels and produce electric power using alternative energy sources. Of the Alpine countries, Germany and, especially, Austria are front runners in the field.
Another boost to the achievement of autonomy of power through renewable sources has come from the difficulty of supplying traditional fuels to inaccessible mountain areas. Narrow, unsurfaced roads make access difficult for diesel delivery tankers; many places are not connected to gas or electricity networks.
In such cases the only way to have hot water may be to install solar panels. These are made up of double walled glass tubes, inside which is a thin copper tube; a very little water runs through this tube, which functions as an absorber.
With a solar panel of 1 – 1.5 sq mt , enough water can be heated for the needs of one person, and up to 30% of heating requirements, as long as a low-temperature system is used.
On suitable terrain, it is now possible to produce heat by exploiting the heat differential between the deep soil (between 50 and 150 mt the earth’s temperature is always constant) and the surface. A geothermal pump can be used to extract heat from, or return it to, the soil, heating or cooling the house as required.
However, a readily available source of good wood is still the commonest means of heating in the mountains. Wood energy can actually be regarded as a renewable energy source, if rational forestry techniques are used.
But the real problem of energy supply in the mountains is that of electricity. It’s in this field that photovoltaic solar panels are coming into their own. To get the maximum possible power, the panels must be fairly large, well-exposed and at an inclination of 35%. In areas where the beauty of the architecture is not a significant feature, the roof could be replaced with a “solar roofâ€. Otherwise special “solar sheds†could be built, as storage space for a variety of purposes.
Lastly, in windy areas a good solution might be to use wind generators. Currently on the market are models from 1 to 10 Kw, which can produce energy even at low wind strength, and which can shut off automatically if the wind exceeds a certain intensity. It may also be possible to “return†excess power to the electricity network, or, when this is not possible, to store unused power via a system of batteries.
