Biomass project (Zlatna Panega cement plant, Bulgaria)
In the spring of 2010, the Zlatna Panega cement plant, in collaboration with the Bulgarian Science Academy, selected and planted experimentally five types of fast-growing species (two grass species and three tree species) or “Energy Crops”. These crops are planted on land located around the plant, owned by the company.
The aim of the experiment is to determine, which of the species are most suitable for growth in the region of Zlatna Panega. This experiment will determine which of them are most environmentally, socially and economically suitable to be grown by local farmers and then sold to the plant for heat recovery.
The selected energy crops are chosen according to the following criteria:
- The species are perennial, they are planted once and only harvesting and bailing is needed for period of 15-20 years.
- The species should grow well on poor lands and require minimal maintenance, keeping expenses as low as possible.
The grass dries itself on the field, reaching moisture levels lower than 20%, depending on the season. Because of the perennial type and qualities of the grass, the soil is preserved, because fewer pesticides and fertilizers are required and the roots enrich and improve the soil.
The chosen species must have high annual productivity. Data indicate that the yield varies between 0.8 and 2 tons per 1000 m2, sometimes even 3-4 tons, depending on the climate and the quality of the soil.
The experiment started in the beginning of 2010 and will continue for three years, given that the energy crops need three years to reach their maximum growth. The final results must be evaluated in the beginning of 2013 after the second harvest is complete.
In the winter of 2012 the first harvest will be completed for the (50% of maximum growth) grasses. Trees should be harvested over a five year period.