The development of renewable energies in the Free State of Saxony during the last decade has been very positive. During the period 2000 to 2010 the share of renewable energies in Saxon gross electricity consumption increased from 3.9 % to 15.3 % (SAENA 2012a) (Fig. 7). The State Govern-ment of Saxony intends to increase the share of renewable energies to 24 % by 2020 (Freistaat Sachsen 2009).
Renewable energies have become an important element of the economy of Saxony. They ge-nerate economic growth, enhance the regional value added and create new jobs. In 2010 about 11,000 new jobs were created and the total turnover in the renewable energy sector amounted to EUR 3.8 billion (SAENA 2012a).
Fig. 7: Share of renewable energies in Saxon gross electricity consumption between 2000 and 2010 (* preliminary estimate) Source: SAENA 2012a
The particular forms of renewable energies differ from each other with regard to their purpose – the production of electricity and heat. Wind power plants, photovoltaic power plants and hydro-power plants are only generating electricity. The energetic use of biomass in combined heat and power stations or biogas plants produces electricity and heat, whereas geothermal power stations and solar thermal plants are only producing heat. Particular trends of the specific renewable
ener-gy sections wind enerener-gy, hydropower, solar power, bioenerener-gy and geothermal power are outlined as follows:
5.1 Wind Energy
The era of wind energy in Saxony started in the year 1992 when the first five wind turbines were installed in the Ore Mountains (Erzgebirge). Since 1992 the wind energy sector has increased rapidly. By the end of 2010, the number of installed wind power plants amounted to 817 (with an installed power of 957 MW) (SAENA 2012a). In the year 2010 about 1,335 GWh of electricity were produced by wind power plants in Saxony. This corresponds to a share of about 8 % of the Saxon net electricity consumption (SAENA 2012b). Today, wind energy is the leading renewable energy sector in Saxony and it will maintain this status in the medium term (Fig. 9a).
Large parts of the regional potentials for wind energy have already been exhausted and only a few locations for the installation of wind power plants are still available. As a result ‘repowering’
– the replacement of old wind turbines – will become more and more important to increase the performance of this particular renewable energy sector also in the future. In the middle and in the long term it will be possible to cover about 12 % of total power need in Saxony by repowering and the construction of new wind power plants.
5.2 Hydropower
At the moment the number of hydropower plants in Saxony amounts to 295 with an installed power of 87 MW. In the year 2010 about 320 GWh of electricity were produced by hydropower plants. Correspondingly, a share of about 1.4 % of Saxon net electricity consumption could be covered by hydropower (SAENA 2012c). Hydropower plants are predominantly concentrated at rivers – hence, the possibilities for a further expansion of this specific renewable energy sector are limited in Saxony.
5.3 Solar Power
The first solar power plant in the Free State of Saxony was already built in the year 1990 in the vil-lage Oberseifersdorf near the city of Zittau (VEE Sachsen e.V. 2008). In the year 2010 alone pho-tovoltaic power plants with 215 MWp were newly installed in the Free State. Thus, the installed photovoltaic power amounted to 502 MWp by the end of the year 2010. In the same year about 330 GWh of electricity were generated by ca. 16,800 photovoltaic power plants (SAENA 2012a) (Fig. 9c).
The draft of the new Energy and Climate Programme for Saxony (Entwurf des Energie- und Klimaprogramms Sachsen) aims at enhancing the share of renewable energy sources in the an-nual power consumption up to 30 % in 2020 (SMWA 2012). The contribution of solar power will amount to 1,700 GWh respectively 1,900 MWp installed power. It can be expected that the imple-mentation of this programme will lead to the development of enormous potentials especially in the photovoltaic sector.
In 2010 about 40 % of all installed solar power was located in the open landscape. To avoid a further consumption of open areas, the legislative authorities have restricted a further designati-on of open spaces. Instead dump terrains, industrial and military sites as well as roofs should be increasingly used for photovoltaic purposes (SAENA 2012d).
5.4 Bioenergy
The utilisation of biomass for energy production makes it possible to cover a large share of future energy supply in rural parts of Saxony. Already today renewable energies have become a new and lucrative source of income, especially for agricultural enterprises (Fig. 8). The number of power plants fuelled by biomass amounted to 328 (with an installed power of 189 MWel) in the year 2010. According to information of the Saxon Energy Agency, 1,205 GWh of electricity produced from solid, liquid and gaseous biomass were fed into the public grid in Saxony in the year 2010 (SAENA 2012a) (Fig 9b).
While statistics about the production of electricity from biomass power plants in Saxony are available, there is a lack of information about the production of heat.
Fig. 8: Biogas plants operated by agricultural enterprises in the Dresden region (Direktionsbezirk Dresden) Source: own design according to LFULG 2010, p. 11
5.5 Geothermal Power
In the field of geothermal power only near-surface geothermic is used in Saxony until now. In the year 2010 a total number of 957 thermal heat pumps were newly installed. The total number of
thermal heat pumps in the Free State of Saxony increased to 8,488 by the end of 2010. However, most of these installations have only a low heat output (< 30 kW). The total power of all Saxon thermal heat pumps amounted to ca. 107 MWth by the end of 2010 (SAENA 2012e).
Fig. 9a-c: Renewable energies in Saxony 2010 Source: SAENA 2012a