With rising energy prices and diminishing supplies of fossil fuels using the ambient energy around buildings for power generation is bound to increase. The question is: is wind power practical on a domestic scale in Spain?
Spain is the fourth biggest producer of wind power after China, USA and Germany. On Nov 6th 2011, a particularly windy day, 59% of the nation’s power was produced by wind power. So we know its windy in Spain (not just sunny!)
And in fact domestic scale wind turbines can be highly efficient and can have very long working lives. A carefully designed eco house can power its basic needs from a 500 watt or 1 kw turbine depending on household numbers and lifestyle.
Some architects believe that roof mounted wind turbines add to the aesthetics of the building. Others think they are an eyesore.
From a practical point of view there is often no reason why small turbines should not be mounted on and around buildings. Having said that it’s important to note that a roof mounted turbine will generate significantly less power and operate for fewer hours than a turbine sited on a mast with a windy open aspect.
Turbines are usually mounted on steel tube masts ideally hinged near the ground to enable the turbine to be safely lowered for inspection and maintenance. Batteries and inverters can be housed near the mast so only low cost high voltage wiring is run to the point of use.
A careful assessment always be made as to whether the turbines will produce enough power for your needs. They will most likely be assessed in combination with other systems such as photovoltaic panels. A smooth steady air flow is best and that is rarely found close to buildings. To obtain good performance the turbine should be sited 10m above any obstruction within 150m.
Wind turbines which are mounted on buildings should be mounted on a steel or aluminium stub mast which attaches to the building’s structure through twin rubber noise and vibration isolation mountings. They should not be mounted on chimneys for structural reasons and building insurance would also be an issue.
The ability to operate safely in high winds is paramount. Beware of some new companies that are selling inadequately engineered designs and are also making performance claims which are impossible to achieve.
The Future For Wind Turbines Mounted on Buildings In Spain
Design is improving all the time and building integrated wind turbines are being developed which enhance wind flow and power production. The holy grail is to develop turbines which operate at much slower rotational speeds and with lower noise levels than most currently available turbines.
When comparing products look for Low weight / high strength / low installed costs / zero maintenance and fail safe operation in high winds. These are the prerequisites for any successful roof mounted product.
Author: John Wolfendale
Bio: John is a founder of Eco Vida and is passionate about bringing modern design and construction practices to Spain. He believes a home which is warm in winter and cool in summer is largely a matter of design and selective use of materials. He is British and a Chartered Surveyor with 18 years experience living and working in Spain.