The conversion of this type of energy into more easily usable forms, such as the thermal one of a carrier fluid or the electric one, requires devices and systems that over time are becoming more and more evolved and accessible.
Focusing on the conversion of solar energy to electricity, it is necessary to focus on photovoltaic systems: systems consisting of collectors capable of generating a direct current if irradiated by solar radiation.
The two basic components are the modules, the real generators, and the static converter (inverter), which allows to convert the direct current of the module into alternating current, therefore to interface the photovoltaic generator to the national electricity network and to most electricity users.
In recent decades PV has been affected by different types of incentives regulated by a number of laws both at national and Community level with the aim of making such technology mature and developing a market photovoltaic that was able to self-sustain over time without the need for injections of new subsidies.
Another hot topic in the topic of photovoltaics is the connection to the national electricity network; in fact, our network was designed for the local distribution of electricity generated in a few production points, the power plants. With the advent of photovoltaic instead, every point of withdrawal can become a possible point of generation that produces energy in a way not predictable and not programmable. This lack of predictability and programmability generates important complications in balancing energy supply and demand: For this reason, non-programmable electricity sources such as photovoltaics enjoy priority dispatching in our electricity market.
Going into more detail, you can briefly bring back the legislative framework that has affected photovoltaics in Italy in recent years, with particular reference to plants for private and condominiums:
dlgs n. 387 del 29.12.2003
implementation of Directive 2001/77/EC on the promotion of electricity produced from renewable energy sources. The text explains which are the types of authorization procedures (free building activity, complaint of start of activity or single procedure) in relation to the complexity of the intervention and the context where the same is placed, differentiating for the category of energy source used.
the decree introducing for the first time the Energy Bill, that is the first form of incentive for the production of electricity through photovoltaic conversion of the solar source. In this decree there are incentive thresholds based on the power of the plant and the different ways of accounting for energy also on the basis of the installed power. With the First Energy Bill there is an incentive for the energy produced and the possibility to sell the energy produced and not consumed by entering the network.
delibera AEEG n._188/05 del 14.09.2005
This resolution was born as a result of the introduction of the Energy Bill to define the actuator and the modalities for the distribution of tariffs incentives of photovoltaic plants, as provided by art. 9 of the Ministerial Decree of 28.07.05.
deliberation AEEG n. 28/06 del 13.02.2006
With such deliberation the incentive mechanism of the Exchange Sul Posto (SSP) is introduced for the first time the mechanism through which still today are encouraged the plants of production from renewable sources with power less than 200 kW. With such deliberation the technical/economic conditions of the Service of Exchange On the place of the electricity produced from plants fed by renewable sources of a nominal power not exceeding 20 KW as provided by art.6 of dlgs n are dictated. 387 of 29.12.2003 (the threshold will then be increased to 200 kW for plants which entered into operation after 31.12.2007).
àˆ the decree of the Second Energy Bill aimed at stimulating the production of electricity produced by photovoltaic conversion of the solar source. Compared to the previous Energy Bill, bureaucratic simplifications are introduced.
a href=https://www.tettosolare.it/index.php?idsų38&IDT=77″>DM 06.08.2010/a>
Anˆ the decree of the Third Energy Bill aimed at stimulating the production of electricity produced by photovoltaic conversion of the solar source. Continuing on the path of simplification, according to this decreless photovoltaic systems are divided into two categories: plants on buildings and other plants. Another novelty is that the plant can be realized in several phases provided that the last section is put into operation within two years from the commissioning of the first.
Decree of the Fourth Energy Bill. The main difference compared to the previous versions is in the substitution of the incentive tariff with an all-inclusive tariff: the first was a pure incentive on the produced energy while the second is a consideration, already recognised for other renewable sources, for energy fed into the grid. The Fourth Energy Bill also introduces the premium rate for self-consumption.
dlgs.n. 28 of 03.03.2011/
aˆ the implementation of Directive 2009/28/EC on the promotion of the use of energy from renewable sources. The most important innovations defined by the decree regarding the energy efficiency of buildings are the definition of the obligations to use renewable sources in new buildings and subject to renovation and the introduction of the obligation, when buying and renting a building, energy certification of buildings.
DM of 05.07.2012/
àˆ the decree of the Fifth Energy Bill a, valid from 27 August 2012, replaces the previous incentive mechanism although some types of plant will continue to benefit from the previous incentives for a few more months.
Currently the incentive mechanisms of the Energy Bill are no longer active but it is still possible to take advantage of the exchange on the spot that, thanks to a strong reduction in the costs for the installation of a plant, however guarantees a return of the investment in a short time. The on-site exchange makes it possible to maximize the cost-effectiveness of a plant when an important consumption occurs, This means that in the current situation the sizing and design phase has become crucial for the success of the investment: from the analysis of the consumption it must dimensioned a system that is able to cover them during the year with its production.
Another interesting opportunity extended for all 2019 is the possibility to carry in tax deduction the expenses for the realization of the photovoltaic system for a quota equal to 50% of the entire amount spent for the design and the implementation of the same. This opportunity, confirmed by the Budget Law of 2019, is addressed to all subjects subject to IRPEF taxation and therefore is valuable for example for the activities on the common parts of condominiums.
Finally, by ERF Decree 1 of 2019, the reintroduction of new incentives with all-inclusive tariff for photovoltaic systems using a ranking logic that rewards the installation of photovoltaic combined with the removal and disposal of cover made of asbestos. The economic value of the omni comprehensive of tariff provided by the decree ERF 1 is much lower than that which was guaranteed to the plants that came into operation under the different Energy Bill therefore these incentives turn out unattractive, especially for those who have the possibility of self-sustaining a large part of the energy produced.
From what has been said so far it is clear that in the current context a photovoltaic system is an excellent investment provided that there are the right circumstances. Considering for example a condominium, there are mainly two opportunities to take advantage of a photovoltaic system:
To serve the common areas of the building
For the utilities of the single condominiums
In the first case the installation costs and benefits resulting from the intervention are shared among the households, it is possible to deduct the intervention to 50% in 10 years and the deduction will be subdivided in millesimal quotas like any other building renovation. Generally also occupying the entire cover it is very difficult to cover all the requirements of the condominium but it is still possible to obtain an important benefit on the common utilities (lifts, communal lighting, lifting pumps air conditioning and central heating systems). If some condominiums are not favorable they can decide not to participate in the installation expenses renouncing the benefits deriving from the photovoltaic: direct saving in the bill, IRPEF deduction of 50 % and refund for the exchange on the spot of GSE.
Reference is made to Article 5 of Law No. 220 of 11/12/2012. Here are the criteria to be able to decide, in the assembly, the installation of a photovoltaic system in condominium: By mandatory summoning all the co-chairmen to the assembly for approval, the positive vote of at least half of those attending (not of the total) is sufficient only if they represent at least half of the total. The majority has the right to decide for the installation of a photovoltaic system both in case this is realized by the building itself and in case the installation concerns third parties.
In case the installation of the photovoltaic system concerns a single family the possibility of exploiting the common spaces of the building is regulated by art. 7: This reform allows a single housing unit to use roof parts, common parts of the building and suitable spaces of individual property but the execution of the works is never allowed in cases where the same result in damage to the common parts of the building. For interventions of this type the single condominium must communicate its intentions to the administrator who will then carry in assembly such demand with the modalities already seen for a shared system.
Wanting to make a practical example we can consider a shared photovoltaic system, designed for a condominium composed of 40 housing units divided into 2 stairs. With regard to the common utilities, 2 lifts, staircase lighting, outdoor lighting, circulation pumps of the central heating system, intercoms, alarm, the antennas, the gates of the garage and the lighting of the garage. This type of utilities with an own use of a condominium would lead to assume an annual consumption of approximately 75000 kWh/year.
If we assume to have a flat terrace of 250 msup>2/sup> and to use photovoltaic modules monocrystalline of 300 W each, we can safely install a system of power equal to 40 kwp. Using a ballast anchoring system and directing the modules perfectly south, 40 kwp can generate in a year about 56000 kWh of electricity, which in our example correspond to about 75% of the electricity demand for the common utilities.
A plant like the one assumed has an initial cost of estimated 60000, cost that over the years is repaid by the economic benefits obtained from the use of the plant. Let’s see how we predict the trend of cash flows for the investment described by fixing to 25 years the duration of the analysis:
The present business plan to 25 years has been realized considering to change the inverter to the tenth year and calculating the tax deduction IRPEF of 50% in 10 years (5% of the total amount of the offer every year). The simulation previews a rate of increase of the price of the energy pairs to 3.5% annual and a reduction of the electricity production of the system pairs to 1% every year. There is a return of the investment at 5° year and a net value of the investment at the end of life (at 25° year) equal to about 270,000 ; as shown by the technical analysis-economic of the cash flows confirmation how much today the photovoltaic system represents, besides that a technical solution for the reduction of the consumptions and the emissions of greenhouse gases, also an optimal investment from the economic point of view.
Dott. Ing. Michele PULCINI