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Economic payback

In the graphic, every point shows the percentage of the plants subsidized that had a number of hours of use
higher than the value shown on the axis of x.
For instance, the 100% of the plants had a number of hours of use higher than 0, while the 50% had, in year 2009, better performances of about 1000.
The general distribution is strongly influenced by the number of plants that have start the running during the year, so to lower the percentage.
To have a real value of the hours of use, the datas of the plants have been cleansed with reference to the plants that have started the running during the last year,
and to those with a production lower than 500 hours of use, due to technical and/or other problems.
So the medium national value is correspondent to 1.200 hours.
In the following list, the results divided for each region:

Piemonte 1.111 Friuli 1.139 Marche 1.221 Puglia 1.285
Valle d’Aosta 1.109 Liguria 1.133 Lazio 1.278 Basilicata 1.195
Lombardia 1.119 Emilia Romagna 1.115 Abruzzo 1.211 Calabria 1.288
Trentino A. Adige 1.132 Toscana 1.221 Molise 1.129 Sicilia 1.371
Veneto 1.146 Umbria 1.214 Campania 1.226 Sardegna 1.369

In the North the regions are set around 1.125 ore, the best performance is that of the region Veneto (1.146), the worst of Valle D'Aosta (1.109) that is the bottom of the barrel of the power installed.
The central regions have an average amount of hours of 1.233, between 1.214 hours of Umbria and 1.278 hours of Lazio.
The Southern area registers the best performances.
The average of hours is of 1.266, as a result of the coalition of regions such as Molise and Basilicata, that act quite like the regions in the Northern area, with regions like Sicily ande Sardinia set around 1.371 hours.
Furthermore, there has been an analysis of the percentage of the number of plants in the 3 different power ranges according to the hours of use realized.

The production from photovoltain plants in Italy has reached 673,8 GWh in 2009 with an increase of 249% compared to the previous year.
The 43% of the electric energy has been produced in the North with a small decrease compared to the 45% of the previous year;
instead, the importance of the Souths goes from 33% to 36%, while Central Italy, at 21%, decreases of about a percentage point.
All the regions have more than doubled their production compared to the previous year.
In percentage, the most important variation is that of the region Basilicata that passes from 1,9 GWh to 21,7 GWh;
In total, the highest increase is that of the region Puglia with a production increase of 71,6 GWh.


As known, the GSE incentives the production of electric energy by photovoltaic plants with the mechanism of the Feed-in Tarif (CE), with compensative tariffs connected to the class of power and the type of integration of the plant.
The processes for the concession of the incentive cause a time span between the demand of access to the Feed-in Tarif (the plant is already running) and the actual distribution of the compensation.
The time span cancels during the first months of the year next to the year concerning the compensations.

graphic shows the distribution in percentages of the photovoltaic power installed for every type of photovoltaic panel (monocrystalline, polycrystalline, thin foil).
In many regions the most used panels are in polycrystalline silicium, even if the monocrystallyne silicium covers always most of the remaining. In particular, the region involved are Molise and Valle D'Aosta (even if they are the absolute last ones).
At a national level the 55% of the plants have polycrystalline technology, the 37% monocrystalline and 8% other.
Veneto and Lazio are the regions with the highest percentage of thin foil.

The thematic map of the distribution of the photovoltaic power installed and referred the regional soil surface shows how the highest concentration of capacity for each is in Puglia, where we find 11,1 kW installed for each kmq.
It is followed by the region Marche with 6,4 kWe for each kmq and the Lombardia with 5,3 for each kmq.

In 2009 the average daily sun radiation per hour, determined by the analysis of the datas espresse in W/mq referred to the 110 italian provinces, confirms that the months of January and Decembers and, then, February and November are the less sunny of the year.
The average number of hours of daily light goes from a maximum of 12 in February to a minimum of 10 in January.
On the contrary, July, August, May and June have reached the highest peaks of sun during the whole year (medium value max 832 W/mq at 11 in the month of July). The greater number of hours of light have been registered in the month of July (16 hours).


Map of the average solar radiation 1981- 2000

The economic payback of the investment for the realization of a photovoltaic plant depends on many factors, the main ones are shortly described as follows.

The installation of a photovoltaic plant requires a high initial investment, while the running costs are reduced to a minimum, as the fuel (solar radiation) is free; even the maintenance costs are
low, as it is almost free from mobile parts. At the moment the cost of a plant in Italy is about 3500 and 5000 euro for each kilowatt of power installed. Obviously, the lower values are referred to big plants (the photovoltaic centrals), for which it is possible to obtain discounts for big orders, both for the supply of elements and for the installation. Anyway, the supply of the modules is the most relevant cost and it can often go beyond the 60% of the whole plant's cost. The running and maintenance costs per year are usually calculated as about 1 – 1,5 % of the plant's cost. The useful life of the plant is calculated in at least 20 years, and, from the 10th year, it is better to provide extraordinary maintenance interventions for the substitution of some electric components, the inverter above all. It can also be useful to subscribe insurance contracts to assure the plant in case of events such as steal or damages after extreme weather events.

As previously reported in details at point 2.2 the incomes come from:

1. mainly from the compensation tarifs admitted for the electric energy produced by the photovoltaic plant;
the tarifs are different according to the size, type of architectonical integration
and the opportunity to benefit from the prizes for the energetic saving or for other special conditions;

2. in second place, from the valorization of the electric energy produced by the plant
and that can be self-consumed and, partially, distributed in the net, sell to the market or compensated throuth the exchange on the place.

Therefore the incomes are different and they can be influenced by many factors, depending on the technical characteristics of the photovoltaic plant, the type of service, (exchange on the place or sell of energy to the electric network) as well as the chance to benefit of the prizes included in thel DM 19/02/07.

The type of financing for the realization of the photovoltaic plant influence the payback of the investment.
In particular, if the plant has been realized with financing from third parts, it is necessary to keep in mind the effect of the financial duties.

The tax system acts on the following incomes:

1. Incentives obtained for the energy produced by the plant;

2. sell of the energy produced by the plant and sell to the network operator.
The methods of taxation of the above mentioned incomes depends on the type of service (exchange on the place or sell to the network) and on the fiscal profile of the responsible entity (natural person, legal person, condominium, etc.)

In the light of what shown above, it follows that every single action, most of all if realized with commercial aims,
contains peculiar characteristics that can be correctly calculated
only through a specific and careful economic-financial analysis that counts the investment made for the realization of the photovoltaic plant, the expected income, the operation and maintenance costs and the insurance of the plant, of the financial duties and the taxation method to be applied.
If the examination is limited to small plants (1-3 kW), realized on buildings and intended for the exchange on the place, it is possible to make approximate valuations, with general validity, that lead to the following estimates of the payback time of the amount invested:

- Northern Italy: 9 – 11 years
- Central Italy: 7 – 9 years
- Southern Italy 6 – 8 years

The upper extreme of the interval is referred to a plant with an ideal planning and installation, which type corresponds – even partially – to the integration, while the lower extreme is referred to a totally integrated plant, that is included in the cases for which is planned an increase of 5% of the basic tarif and it also benefits from the compensation for the energetic efficiency.

it is clear as the first two bar graphs are quite similar and distinguished by the range included between 1.000 and 1.250 hours of use.
The third diagram on the contrary is different as it describes the systems with power higher than 20 kW in fact,
even if the most relevant range is still the same of the previous ones (1.000; 1.250), the percentage of the plants with hours of use between 1.250 and 1.500 increases, as well as that between 1.500 and 1.750.


For small plants (1 – 3 kWp) with the system of exchange on site the capital payback is as follows:

- Northern Italy: 11 – 13 years
- Central Italy: 9 – 11 years
- Southern Italy: 7 – 9 years

For plants with higher power it is automatically effective the right to sell the energy produced and it is possible to modify the building in order to obtain the bonus for a higher energetic efficiency and in the specific sphere of agricolture, for a disposal of dangerous materials (asbestos, amianthus,…). This represents a further income and so a shorter amortization time.