**6. Conclusions**

Perennial rhizomatous grasses can contribute significantly to the sustainable biomass production due to their high yield potential, low input demands, and multiple ecological benefits. Yields of more than 30 t DM ha−1 have been obtained from rhizomatous grasses. However, biomass yields strongly depend on local soil and climatic conditions.

The issue of primary concern when burning grasses is mineral composition that determines the melting point of ash and the potential for corrosion. Ash content needs to be minimized to avoid fouling problems. Appropriate harvesting time and fertilization application can contribute significantly toward improvement of ash content and ash-melting behavior. There is the possibility of using grasses biomass by blending it with other biomasses with low ash, K, and Cl contents. Further research is required to find the optimal blend of biomass.
