In this article we treat the economic aspect of the choice of a heat pump water heaters. For most cases, it can be argued that there is economic convenience, if you use the heat pump for air conditioning, while such convenience is greatly reduced in applications for the only production of domestic hot water and for heating only.

In the latter case, the most advantageous conditions are obtained with the use of a cold source other than air (water or ground), since the heat pump, with this source, is able to cover the needs alone heat.

The RVF is a technical solution adopted in the building that is to create an outer "smart" for any type of building or building. This "skin" guarantees, through a cushion of air maintained between the external facade and the walls of the building, thermal comfort thus reducing operating costs.

In fact an external façade of this type, also called courtain wall, allows two things that seem irreconcilable: the breathability of the building wall and at the same time protects the latter from rainwater, in substance from rain and from other weathering.

This is thanks to the outer coating which is mounted on a metal frame, directly set against the walls of the building, thus preserving the stable from external atmospheric agents and forming a useful air gap.

While the debate on clean sources Italian is mainly focused on wind and solar power, there is a source that under track or, rather, under the earth, is preparing to meet a period of strong growth, particularly in our country.

We're talking about geothermal energy, the exploitation of natural heat inside the planet: especially in areas where the layers warm (over 90 degrees) are very close to the surface (geothermal anomaly) you can use this heat to produce electricity.

It is a resource certainly not new (in Italian is used for energy production since the beginning of the twentieth century), but that now appears ready to turn, also because of significant news from the regulatory point of view. The initial situation in Italy is not negative: the geothermal generation has known, from 1990 to 2011, an increase of 75%, from 3,222 GWh / year to 5,654 GWh / year, for a total capacity of 772 MW, a figure equal to about half of the installed power throughout Europe.

Energy certification of buildings is a complex challenge, because it is the complex structure of energy consumption that "revolve" around and within them, and the legislation that has been created around it.

What is even more complicated if we consider the fact that on the one hand in the buildings you are entering new elements, such as renewable energy systems, while on the other the actual overall performance under the energy profile of the building depends on the quality materials and the implementation of the same, two aspects that always in construction are issues with many shadows.

On the market there are numerous models pellet-fueled, small concentration of sawdust from untreated wood and pressed, with different aesthetics and technology. Regarding the second aspect of verifying the existence of the basic prerequisites for installing the heater, such as the ability to place the flue and an air intake, that an air hole that must be connected with the outside of the ' home, the presence of an electrical outlet to start up and operation.

First you need to decide whether to opt for the type of air or to the water (hydro). This allows you to produce hot water for domestic use and for the radiators. The air oven allows you to spread the warm air in multiple rooms, after duct system. The dimensions of the room are important, in fact about 30% of the heat produced by the stove remains in the room, so if high power could make uninhabitable.

The Institute of materials for electronics and magnetism of the National Research Council of Parma (Imem-CNR) has developed a process for the production of solar cells that could be very useful for the production of photovoltaic systems to be integrated in ' building. It is a production process of solar cell thin film (Thin Film) that operates at low temperature and allows the use of a wide range of substrates and which was published in the journal "Applied Physics Letters".

"This polycrystalline material, known by the acronym of CIGS (Copper-based technology, indium, gallium and selenium, Ed.) - Says Massimo Mazzer dell'Imem-CNR - is ideal for photovoltaic applications mainly because 'absorbs light very efficiently, but it is however complex to be synthesized in the form of thin film and so far the industrial-scale production of solar modules based on CIGS is therefore not taken off due to the high costs. "

In the mountains we see more and more often, in isolated mountain huts, check solar panels. PV systems are self-employed, similar to those used in mobile homes and boats. These solutions are more and more extended in the countries in the developing world, where the objective difficulties to connect to the national grid community located in inaccessible places are factors that are pushing the demand for stand-alone installations.

Such systems can be directed to power of individual residential units or structured for micro-grids: these are currently the most suitable answer from an economic point of view, social and technical needs of entire communities isolated "

But in countries such as Italy it is possible to create an independent system while having the ability to link up to the national grid?

A solution that is increasingly taking root in our country is that of pellet stoves, which ensure a very efficient operation (75-90% overall efficiency), and have a Btu content (thermal units) 4-5 times higher compared to wood or wood shavings. Pellet stoves also have very low particulate emissions, 50 times less than the old wood stoves, and 2-5 times lower than the most efficient ones.

An opportunity for all consumers interested in this type of equipment is represented by the Decree growth launched in late July, which provides that in the period between 26 June 2012 to 30 June 2013 for works aimed at achieving energy savings and exploitation of renewable energy is provided for a tax deduction of 50%, increased from the previous 36%. The maximum deduction has also been raised from 48,000 to 96,000 euro.

Soon it will be possible to realize the photovoltaic effect also with architectural elements of existing buildings, through the application of innovative coating materials. And 'the promise - and the goal - Specific Project, Sustainable Product Engineering Centre for Innovative Functional Industrial Coatings. This is an initiative which was set up at the University of British Swansea, who last October was awarded a grant of £ 20 million.

The premise of the project is simple and recalls the example of the United Kingdom, where there are buildings with roofs and facades that have an area of over four billion square meters. A considerable part of this surface could be used to capture the sun's rays and convert them into energy. The objective is thus to develop affordable coating materials and solar devices that can replace the covers traditionally used and come to 2020, through these technologies, to produce a third of the renewable energy generated in the UK.

The 60 per cent of Italians considers environmental sustainability a necessity. For the 28 percent is "a 'opportunities for development of the economy." And 'apparent from the third report "The Italians, the energy of the sun and the green economy", presented yesterday by Univerde Foundation at the conference Green Economy, New Society within Ecomondo, the International Fair of Material and Energy and Sustainable Development taking place these days in Rimini. The report gives an account of the results of the research, commissioned to IPR Marketing, conducted on a sample of a thousand Italian and older, interviewed on environmental sustainability.