**1. Introduction**

The production of marginal cereals has seen significant developments in the European Union related to the development of the organic farming sector. The typical marginal wheat species in the Czech Republic are Einkorn, Emmer, and especially Spelt wheat [1,2]. They can be defined as the cultural hulled wheat species, which replace, expand, and supplement the existing range of cereals and contribute to broadening the spectrum of crop production [3]. These marginal cereals have usually lower harvest index but have less input intensity requirements. Thanks to this aspect, these grains are particularly suitable for organic farming systems [3–5]. The benefits of introducing these marginal cereal species include extending the food spectrum, maintaining the production capacity of the soil, and the efficient use of marginal and less-favored areas [6,7]. However, the disadvantages are low yields (low harvest index) and uneven ripening, which causes large losses during harvesting [5,8]. The processing of these hulled wheat species generates a relatively large amount of waste-chaff [9], which can be used in various ways, for example, can be composted [10], used as litter [9] or as an additive to building materials [11], or could be directly put back to the agricultural land to help to maintain the soil fertility [2,5]. Due to the high content of mycotoxins, however, it is not recommended to use chaff from hulled wheat as litter and it is preferable to use it for energy production and to burn it [9], optimally in the form of pellets [12,13]. The energy use of such residual agricultural biomass has great potential not only across the EU [14]. The potential for energy utilization, the energy parameters of chaff and the removal rate, including pelleting issues, have been summarized for Spelt and Emmer in some studies [9,10,13,15]. However, the crop residue removal for biofuel production can have a significant impact on crop productivity, soil health, and greenhouse gas emissions [16].

In addition to Spelt and Emmer wheat, this manuscript also evaluates the energy parameters of Einkorn chaff. The energy use of chaff of these marginal cereal species is often perceived as an environmentally friendly source of energy, because it is energy from biomass. However, it has to be considered in terms of inputs into the cultivation process. This work aims to point out environmental aspects related to hulled wheat chaff and quantitative and qualitative parameters of individual wheat species using the Life Cycle Assessment (LCA) method.
