Survey of Energy Resources 2007
Solar Country Notes
The Bulgarian WEC Member Committee reports that average annual solar hours are about 2 150 and annual average solar radiation resources 1 517 kWh/m2. The total theoretical potential of solar energy is 13 103 ttoe, and the available annual potential is about 390 ttoe.
For the 2004 edition of the present Survey, the Member Committee observed that Bulgaria could be divided into three zones according to the solar insolation received, namely:
Zone A - encompasses regions in the south east, part of the southern Black Sea coastal region and the valleys of the rivers Struma, Mesta and Maritza. The amount of sunshine is over 2 200 h/yr and the total solar radiation received on a horizontal surface is greater than 1 600 kWh/m2.
Zone B - encompasses regions in the Danube plain, the Dobrudja region, the Trace lowland, west Bulgaria, the Balkan hollow fields and Stara Planina mountain regions. The amount of sunshine ranges from 2 000 to 2 200 h/yr and total solar radiation from 1 500 to 1 600 kWh/m2.
Zone C - encompasses the remaining parts of Bulgaria, mainly the mountainous regions, where sunshine is less than 2 000 h/yr and total solar radiation less than 1 500 kWh/m2.
Installed PV capacity at end-2005 is reported to have been negligible and no data are available regarding the installed capacity of solar water-heating devices. At present there are no grid-connected systems for utilising solar energy for electricity generation.