This study aimed to evaluate the effect of nitrogen (N) application in the biomass yield and energetic characteristics of biofuels (fresh and briquettes) of elephant grass grown in tropical conditions. The experiment was carried out during two consecutive harvests, and the following nitrogen fertilizer doses were evaluated: 0, 50, 100, 150, and 200 kg of N ha⁻¹ year⁻¹. Biometric variables, biomass yield, total accumulated nitrogen, and C:N ratio and biomass energetic characterization were carried out. Briquettes were produced for the evaluation of the energetic, physical, and mechanical characteristics. Nitrogen application influenced the elephant grass yield growing in tropical conditions. The biomass yield reached 43 Mg ha⁻¹ in the second harvest. The application of 100 kg ha⁻¹ N promoted greater efficiency in the use of N and biomass yield. Thus, this is the recommended dose for cultivation of elephant grass for energy purposes in the edaphoclimatic conditions of the Cerrado biome (Brazilian Savannah). Elephant grass presented high heating value (17,196 kJ kg⁻¹), ash content (4.77%), and bulk and energy density (206.00 kg m⁻³ and 0.84 Gcal m⁻³) that make it suitable for use as an energy resource in the fresh form. However, the production of briquettes improved its energetic characteristics. The application of N did not change the high heating value of biomass and the characteristics of briquettes.

这项研究旨在评估氮肥对热带条件下生长的象草的生物量产量和生物燃料（新鲜和煤球）的能量特征的影响。在连续两次收获期间进行了该实验，并评估了以下氮肥剂量：0、50、100、150和200 kg N ha - ¹年^-1。进行了生物测定变量，生物量产量，总累积氮，C：N比和生物量能量表征。生产出团块用于评估能量，物理和机械特性。氮的施用影响了热带条件下象草的产量。生物量产量达到43 Mg ha ^-1 在第二次收获。100 kg ha ^-1 N的施用提高了氮的利用效率和生物量产量。因此，这是在塞拉多生物群系（巴西萨凡纳）的海温气候条件下，出于能源目的种植象草的推荐剂量。象草具有很高的发热量（17,196 kJ kg ^-1），灰分（4.77％）以及体积和能量密度（206.00 kg m ^-3和0.84 Gcal m ^-3），使其适合用作美国的能源。新鲜的形式。但是，煤球的生产提高了其能量特性。氮的施用并没有改变生物质的高发热量和团块的特性。