The study evaluated physicochemical properties of bio-waste as a potential biofuel in the form of leaves from ‘Regent’ grapevines grown on six different rootstocks and a control grown on its own roots for three years of cultivation. An elemental analysis was carried out, determining the content of carbon, hydrogen, nitrogen, and sulphur in the leaves tested. A technical analysis of the biofuel was also carried out to determine the content of moisture, volatile matter, and ash. The calorimetric method was used to determine the higher heating value for the material. Fixed carbon and oxygen carbon was calculated based on the elemental and technical analyses. The study showed that the type of rootstock and the year of cultivation influence the amount of leaves obtained from the cultivation area. Leaf entrustment per hectare ranged from 1,140,868.02 in rootstock 161-49 to 1,265,286.7 Mg∙ha–1 in rootstock SO4. Regardless of the year of the study, shrubs grafted on 125AA rootstock and the control had the highest combustion heat of 17.5 MJ∙kg–1 and 17.6 MJ∙kg–1 respectively, while 5BB rootstock had the lowest combustion heat (16.4 MJ∙kg–1). Statistical analysis showed no significant effect of test year on the elemental and technical parameters evaluated. It was observed that regardless of the evaluated parameter and the type of rootstock in most parameters, the values in 2022 were the highest, while in 2021 they were the lowest.

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Biogas plants are one of the most stable sources of renewable energy. Currently, there is a noticeable increase in the amount of post-production residues from agricultural production and agri-food processing (fruit and vegetable processing, fermentation, beet pulp, or lignocellulosic waste), which, can be used for biogas production after appropriate pretreatment. The aim of this study was to examine the possibility of using the biomass produced during the cultivation of grapes on a selected farm as a substrate for a biogas plant, taking into account the production process. The research was carried out in 2018–2020 in a vineyard located in the Sandomierz Upland in the south-eastern part of Poland. Own rooted vines were grown as a single continuous string with a trunk height of 40 cm and a length of one fixed arm approx. 0.9 m, on which six pivots were left every year after applying a short cut, from which 12–16 fruit shoots were derived, the so-called grapevines. Leaves were collected at random from three locations on the fruiting shoot, a total of 30 leaves in each replicate. Each sample consisted of 1/3 of the leaves collected at the bottom, 1/3 in the middle, and 1/3 at the top of the canopy. Leaf area was estimated with a model 3100 area meter on a sample of 30 leaves from each replicate. Both the quantity and quality of the obtained material as a substrate for methane fermentation were evaluated. Biogas yield tests in optimal conditions for mesophilic bacteria were conducted on three substrate samples referred to as ‘Regent’, ‘Seyval Blanc’, and ‘Solaris’. The yields of the tested material ranged from 51.0 to 59.0 Nm ³ biogas per Mg of biomass.