Photovoltaic systems on roofs - lofts
Photovoltaic on roofs
The Greek government subsidized the installation of PV systems up to 10kW power on buildings used as residences or very small enterprises through the "Special program for the growth of photovoltaic systems in buildings and mainly on lofts and roofs" (Official Journal of the Hellenic Republic 1079/Β/2009)
Conditions to access the program
Active connection to NEC
Roof or loft area between 30 and 170 square meters
Part of hot water needs covered by solar thermal system
Cost - Depreciation of investment
An average PV system costs as much as a good car. However, the car has continual expenses while a PV system provides an income for more than 25 years. In any case, the return of a PV system is better than saving money in a deposit account or investing it in bonds or in the stock exchange. Moreover, think that its returns are set and guaranteed for 25 years.
Solar irradiation in each region can be determined through the European Unions’ webpage.
Click here for more information.
In Greece, a PV system produces around 1.150-1.500 kWh/kW annually. Obviously in the south of the country, the system produces more electricity than in the north. PV systems produce 1.250-1.450 kWh/kW in Athens, 1.150-1.275 kWh/kW in Thessaloniki and 1.400-1.500 kWh/ kW in Crete or Rhodes. Roof should preferably face south and not be shaded.
Let’s see an example
NEC pays 0.55 euro per kWh produced A 5 kWp PV system costs about 17.000 € + VAT (prices for January 2010). The annual electrical energy production of 7.000 kWh (Athens, south-facing roof), provides an annual income of 3.850€.
NEC deposits the money in your bank account after subtracting the money you have to pay for your electricity bill. Based on these numbers, the time needed to get back one’s initial capital can be easily calculated.
Procedures to receive a licence
Application to the NEC
Contract with the NEC
Application for the small-scale construction work to the Urban Planning.
Our company offers advisory services for finance programs up to 100% of purchase and installation cost with a reimbursement period up to 25 years.
PV parks contribute substantially to the Distributed Power Generation that consist the new model for development of the modern electrical energy production, transmission and distribution systems.
Law Ν. 3468/06 opened the way for investments in PV parks but because of the high number of applications submitted, this law became inactive one year later.
Law Ν. 3734/09 tried to heal some weaknesses of the previous one and it partly succeeded. The new law for the RES is about to become law of the country very soon.
A photovoltaic park consists of:
The photovoltaic panels
The inverter that transforms the voltage from 12/24/48 V DC to 220 V AC
The mounting system (fixed or with trackers on single or double axis).
Photovoltaic parks economics
The equipment and installation cost for a PV park is about 2.9 €/ Wp. (prices for May 2010). If a single-axis tracking system is added, installation cost is increased by about 20%.
Insurance and safekeeping (mandatory for bank loan)
Staff expenses (e.g. caretaker, panel cleaning)
Administrative costs (e.g. accountant, telephone fees)
Average annual cost is estimated to be 0,5-1,5 % of the total one.
All equipment are certified according to international standards. Manufacturers certify
For the photovoltaic panels 2-5 years, 10-12 years that they operate with more than 90% of nominal power and 20-25 years with more than 80% of nominal power.
For the inverters 2-5 years
Mounting systems are certified according to resistance and statics specifications: DIN 1055, Eurocode 9 or equivalent.
When the installation is completed, our engineers record the production, carefully recheck all connections and finally they compose the delivery protocol.
The project is complete. The collaboration continues
The company is committed to provide solutions for any technical problem occurs for the entire period of the investment. In case immediate repair is not possible we temporally replace the broken part, so that the operation of the system is not interrupted.
Photovoltaic parks are a profitable investment. All that is required is an initial capital and the will to take the risk. The Greek sun will reward you for sure.