# Biomass from Green Areas and Its Use for Energy Purposes
## 4 Conclusions and Perspectives  
Due to the growing demand for electricity, the consumption of fossil fuels is growing, which is associated with the emission of greenhouse gases that pollute the natural environment. Considering the huge amounts of biomass produced in parks and gardens, it is worth paying attention to its potential and use as a source of renewable energy. By producing pellets from this type of raw material, we obtain a solid fuel that is environmentally friendly. The results of analyses of pellets produced from biomass obtained from green areas (i.e., chestnuts, acorns, and pine and fir cones) indicate that these types of biomass can be used for energy purposes. The results of mechanical properties tests indicate that pellets made of chestnut and pine and fir cones are of appropriate quality to be used in boilers with an automatic feeding system. The low value of the destructive force for acorn pellets proves that this type of pellet is very susceptible to crushing and breaking, which significantly hinders its storage, transport, and use in the power industry. In the case of the mixture of sawdust from coniferous trees, no increase in the mechanical strength of the analyzed pellet was noted. It would be advisable to use other admixtures with the raw material of acorns in order to check the resistance to mechanical damage of the produced pellet. The calorimetric analysis showed that the tested solid fuels are of high quality. This is evidenced by the very low ash content for the analyzed types of pellets--below 3%--and their high calorific value. The emission of NO\({}_{\mathrm{x}}\) and SO\({}_{2}\) in the combustion of pellets corresponds to the current emission standards for fuels produced from biomass in the area of the European Union. Biomass from green areas is mainly composted in landfills. Determining its energy quality allows one to determine the direction of its use and thus solve the problem of undeveloped biomass from green areas. The research results are promising for an attempt to produce solid fuels from biomass and use it in small household installations and in the power industry. The use of waste biomass, and thus the replacement of non-renewable raw materials perfectly, fits into the ideas of the circular economy. The depletion of natural resources and the increase in their prices are the main reasons for the creation of the concept of a circular economy. Biomass is considered carbon-neutral because it is assumed that its combustion emits the same amount of carbon dioxide that is fixed in the next vegetation period during plant growth. Therefore, it is claimed that biomass or biofuels have a closed carbon dioxide cycle. It is worth paying attention to the problematic issue of biomass production. It is important that it complies with the principles of sustainable development. Appropriate management of waste from green areas will reduce environmental pollution resulting from composting and thus mitigate climate change. Another good example of the idea of closed-loop waste management is the use of leachate from landfills as a medium for anaerobic digestion of coal substrate. As a result of this process, methane is used for energy production and fertilizer. The presented results require further research in order to obtain information about the potential of biomass from green areas, which has not been fully understood and used so far. In addition, it is important to disseminate information about the high quality of fuels produced from waste biomass from green areas that have been tested so far. It is worth paying attention to other types of biomass produced in urban and rural green areas as well. There are many different wastes generated during maintenance work, the properties of which should be tested in order to determine their suitability for energy purposes. This experiment was a pilot study in order to demonstrate the usefulness of the analyzed biomass materials for the possible industrial production of solid fuels.