Mycelium-based insulation

Abstract

The present invention relates to a method for producing an insulation panel that substantially consists of mycelium, comprising the following steps: a. providing a growing substrate for the mycelium to grow on in a receptacle or mold, wherein the growing substrate has been previously sterilized; b. providing a basidiomycete-inoculated substrate in and / or on the growing substrate; c. growing mycelium of the basidiomycetes in / on the growing substrate for a minimum predetermined time, wherein the temperature is substantially between 20°C and 27°C, and wherein the relative humidity is at least 60%; d. monitoring predetermined parameters of the mycelium; e. harvesting the mycelium when the predetermined parameters meet predetermined threshold values; f. drying the harvested mycelium to a moisture content below 10%. The method further comprises the use of hemp shives and hemp fibers in specific weight ratios, which results in improved thermal insulation and increased durability of the produced insulation panels. The sterilization of the growing substrate minimizes the risk of contamination, which leads to a more reliable and uniform production process. The insulation panels are environmentally friendly, biodegradable and offer improved structural integrity.

Description

[0001] MYCELIUM-BASED INSULATION

[0002] TECHNICAL FIELD

[0003] The present patent relates to a method for the production of insulation panels consisting mainly of mycelium. This method comprises cultivating mycelium on a growing substrate that primarily comprises hemp, in a mixture of shives and / or fibers. The method comprises steps such as sterilizing the growing substrate, providing a basidiomycete-inoculated substrate, allowing the mycelium to grow under controlled temperature and humidity, monitoring growth, harvesting (and killing) the mycelium, and drying to a certain moisture content. These insulation panels offer advantages such as durability and environmental friendliness.

[0004] PRIOR ART

[0005] Insulation panels are frequently used in the construction sector to provide thermal and acoustic insulation. However, traditional insulation materials such as fiberglass, foam plastic, and mineral wool have several disadvantages. These materials are often not environmentally friendly (often also of fossil origin), can contain harmful substances, and are often difficult to recycle. Furthermore, the production of these materials can consume a lot of energy and emit significant amounts of CO2. There is therefore a growing demand for sustainable and environmentally friendly alternatives.

[0006] Additionally, the prior art panels often release chemical vapors due to degradation and in case of fire.

[0007] Mycelium, the vegetative part of fungi, offers a promising solution due to its natural and biodegradable properties. However, current methods for cultivating myceliumbased insulation materials are not yet optimal.

[0008] There are challenges related to the control of growth parameters, the homogeneity of the growing substrate, and the final quality and consistency of the produced insulation material. Additionally, there is still insufficient knowledge about the longterm performance of mycelium-based insulation materials under various environmental conditions. These problems limit the large-scale application of mycelium-based insulation materials in the construction sector, despite their promising potential. Existing solutions have already been described in "Mycelium based composites: A review of their bio-fabrication procedures, material properties and potential for green building and construction applications" by K.K Alaneme et al, "Engineered mycelium composite construction materials from fungal biorefineries: a critical review" by M. Jones et al, "An evaluation study of mycelium based acoustic absorbers grown on agricultural by-product substrates" by M.G. Pelletier et al, "The mechanical possibilities of mycelium materials" by R.J.J. Lelivelt, "The production process and compressive strength of mycelium-based materials" by R.J.J Lelivelt, "Mechanical, physical and chemical characterization of mycelium-based composites with different types of lignocellulosic substrates" by E. Elsacker et al, in DE102021134036A1 and in WO2024 / 062136A1. However, none of these documents provide a suitable insulation panel that meets the requirements of thermal insulation, structural strength, and allows for a simple production process.

[0009] The present invention aims to solve the above-mentioned problems.

[0010] SUMMARY OF THE INVENTION

[0011] The present invention relates to a method for producing insulation panels that substantially consist of mycelium. The method comprises the following steps: providing a growing substrate that preferably consists for the most part of hemp, inoculating the substrate with basidiomycetes, allowing mycelium to grow at a temperature between 20 and 27°C and a relative humidity of at least 60%, monitoring predetermined parameters, harvesting the mycelium upon satisfaction of threshold values, and drying the harvested mycelium to a moisture content below 10%, preferably below 5%.

[0012] The method can be further refined by the use of specific mixtures of hemp shives and hemp fibers, the addition of flour to the substrate, and the use of microwave radiation for drying. The advantages of this method include improved thermal insulation properties, increased durability and resistance to environmental factors, faster production by artificially introducing cavities, and an environmentally friendly solution through the use of renewable raw materials such as hemp and mycelium. Moreover, the specific composition of the growing substrate results in better insulation characteristics, energy efficiency, and structural integrity of the produced insulation panels. The sterilization of the substrate minimizes the risk of contamination and ensures a more reliable production process. The produced insulation panels are lightweight, biodegradable, and offer consistent product quality through a uniform distribution of nutrients in the substrate.

[0013] In certain variants, a suitable plant-based product can be chosen for the growing substrate, such as straw, flax, bamboo, etc. Preferably, this is tailored to the geographical location where the panel is manufactured. Mixtures of different types of plant-based products can also be chosen.

[0014] In a second aspect, the invention relates to a mycelium panel obtained according to the first aspect.

[0015] DETAILED DESCRIPTION

[0016] Unless otherwise defined, all terms used in the description of the invention, including technical and scientific terms, have the meaning as commonly understood by a person skilled in the art to which the invention pertains. For a better understanding of the description of the invention, the following terms are explained explicitly.

[0017] In this document, "a" and "the" refer to both the singular and the plural, unless the context presupposes otherwise. For example, "a segment" means one or more segments.

[0018] When the terms "about" or "around" are used in this document with respect to a measurable quantity, a parameter, a duration or point in time, and the like, variations of + / -20% or less, preferably + / -10% or less, more preferably + / -5% or less, even more preferably + / -1% or less, and even more preferably + / -0.1% or less than and of the cited value are intended, insofar as such variations are applicable to the described invention. However, it must be understood that the value of a quantity used where the term "about" or "around" is used, is itself specifically disclosed.

[0019] The terms "comprise," "comprising," "consist of," "consisting of," "provided with," "have," "having," "include," "including," "contain," "containing" are synonyms and are inclusive or open terms that indicate the presence of what follows, and which do not exclude or prevent the presence of other components, characteristics, elements, members, steps, as known from or disclosed in the prior art.

[0020] Quoting numeric intervals by the endpoints includes all integers, fractions, and / or real numbers between the endpoints, including those endpoints.

[0021] The term "growing substrate" in the present invention refers to a material that provides the necessary nutrients and environment for the growth of mycelium. In this invention, the growing substrate consists primarily of hemp, including hemp shives and / or hemp fibers.

[0022] The term "basidiomycete-inoculated substrate" in the present invention refers to a substrate that has been inoculated with spores of basidiomycete fungi or mycelium. This substrate serves as the initial source of fungal growth that will colonize the growing substrate.

[0023] The term "mycelium" refers to the vegetative part of a fungus, consisting of a network of fine white filaments (hyphae). In this invention, the mycelium grows on the provided growing substrate and ultimately forms the main component of the insulation panel.

[0024] The term "hemp shives" in the present invention refers to the woody core parts of the hemp plant, which are used in the growing substrate for the mycelium to grow on.

[0025] The term "hemp fibers" refers to the fibrous parts of the hemp plant. In the context of this invention, they are used in the growing substrate and are subject to specific length requirements as detailed in the claims.

[0026] The term "moisture content" refers to the moisture content of the mycelium, measured as a percentage of the total weight. The drying process aims to reduce this moisture content to less than 10%, preferably less than 5%, to ensure the stability and performance of the insulation panel.

[0027] The term "basidiomycetes" refers to fungi belonging to the Basidiomycota division, which includes species capable of breaking down lignocellulosic materials. In this invention, the preferred basidiomycetes are from the genus Ganoderma. The term "receptacle" or "mold" refers to the container or mold in which the growing substrate and the basidiomycete-inoculated substrate are placed for the mycelium growth process.

[0028] The term "cavities" refers to artificial voids introduced into the mycelium during growth to potentially enhance certain properties of the final product.

[0029] The term "sterilizing" refers to a process for eliminating all life forms, including spores, from the growing substrate before inoculation with the basidiomycete- inoculated substrate. This can be done via microwave irradiation, but also via steam sterilization, RF (radio frequency) sterilization, etc.

[0030] The term "coating" refers to applying a coating to the harvested mycelium to provide additional properties, such as water resistance or mechanical strength.

[0031] The term "microwave radiation" refers to the use of microwave radiation during the drying process and / or sterilization process to reduce the moisture content and / or kill any remaining fungal spores or mycelium, thereby ensuring the stability of the final product. The term "microwave radiation" hereby typically comprises radiation with a frequency between 300 MHz and 3000 GHz, and often between 1 and 100 GHz.

[0032] The term "Radiofrequency radiation" or "RF radiation" refers to the use of radiofrequency waves, during the drying process and / or sterilization process, to reduce the moisture content and / or kill any remaining fungal spores or mycelium, thereby ensuring the stability of the final product. The term "radiofrequency radiation" hereby typically comprises radiation with a frequency between 1 to 300 MHz, but in other definitions also includes microwave radiation, and then extends up to 3000 GHz, or up to 100 GHz.

[0033] In one aspect, the invention relates to a method for producing insulation panels that consist primarily of mycelium. The mycelium is grown on a growing substrate that primarily comprises hemp, in a mix of shives and / or fibers, wherein the best result is achieved with primarily shives. The process begins with providing a basidiomycete- inoculated substrate, from which the mycelium grows and feeds on the growing substrate. This is done at a temperature between 20 and 27°C, and a relative humidity of at least 60%. The mycelium is harvested after certain desired values are reached and is ultimately dried to a moisture content of at most 10%, preferably at most 5%.

[0034] The sterilization of the growing substrate results in a cleaner growth process. By sterilizing the substrate, unwanted microorganisms are eliminated, which leads to a more efficient and more controlled growth of the mycelium. This contributes to the consistency and quality of the produced insulation panels. The sterilizing is preferably done via microwave sterilization, but alternatively via steam sterilization, RF sterilization, or other heat sterilization techniques (or still others, such as UV sterilization, etc.).

[0035] The choice of hemp shives as the main component of the growing substrate offers multiple advantages. First, hemp shives are lighter compared to other materials, which facilitates the transport and installation of the insulation panels. This can lead to lower transport costs and simpler installation, which is especially advantageous in large-scale construction projects.

[0036] Additionally, the produced insulation panels are biodegradable. This means that after use, they can be broken down in an environmentally friendly manner, without leaving behind harmful residues. This offers a significant advantage compared to traditional insulation materials that are often difficult to recycle and contribute to the accumulation of waste.

[0037] The process for cultivating mycelium on hemp shives can be optimized by precisely controlling the temperature and relative humidity. Although the optimal temperature is between 20 and 27°C, the process can also be effective at temperatures between 15 and 30°C, more preferably between 18 and 28°C, even more preferably between 19 and 27°C, and most preferably between 20 and 25°C. Likewise, the relative humidity can vary from at least 50% to a maximum of 80%, more preferably between 55% and 75%, even more preferably between 58% and 70%, and most preferably between 60% and 65%.

[0038] Drying the mycelium to a moisture content of at most 10% is crucial for the durability and performance of the insulation panels. This can be achieved by drying the mycelium at different temperatures and times depending on the specific needs of the production process. Preferably, the mycelium is dried to a moisture content of at most 8%, more preferably at most 7%, even more preferably at most 6%, and most preferably at most 5%.

[0039] In a further embodiment, the growing substrate can also contain other fibrous materials in addition to hemp shives, such as flax fibers or wood fibers, to further improve the properties of the insulation panels. These materials can be mixed in various proportions to achieve the optimal balance between weight, strength, and insulation capacity.

[0040] By following this method, high-quality, environmentally friendly insulation panels can be produced that not only offer excellent thermal properties but also contribute to more sustainable construction practices.

[0041] In a preferred embodiment, the growing substrate for cultivating mycelium comprises hemp shives as the main component. The use of hemp shives as the main component of the growing substrate enables a more efficient and productive growth of mycelium. The growing substrate can further optionally contain other components, such as hemp fibers, which can improve the structure and nutritional value of the substrate. The shives are typically also (more simply and efficiently) reducible to a smaller length, and provide a better nutrient medium for the mycelium.

[0042] Preferably, the growing substrate is inoculated with basidiomycetes, which are known for their ability to grow quickly and effectively on hemp shives. This leads to an increased production of mycelium, resulting in a higher yield of the final product. The growing conditions, such as temperature and humidity, are preferably carefully controlled to ensure the optimal growth of the mycelium. The temperature is preferably between 20 and 27°C, more preferably between 21 and 26°C, even more preferably between 22 and 25°C, even more preferably between 23 and 24°C, and most preferably around 24°C. The relative humidity is preferably at least 60%, more preferably at least 65%, even more preferably at least 70%, even more preferably at least 75%, and most preferably around 80%.

[0043] After the mycelium has reached the desired growth stages, it is harvested and dried to a moisture content of at most 10%, preferably at most 8%, more preferably at most 6%, even more preferably at most 5%, and most preferably around 4%. This low moisture content helps to preserve the structural integrity and insulating properties of the resulting panels. By using hemp shives as the main component of the growing substrate, not only are the efficiency and productivity of the mycelium growth improved, but it also contributes to a more sustainable and environmentally friendly production process.

[0044] In a preferred embodiment, the method makes use of shorter hemp fibers for cultivating the mycelium. The use of these shorter fibers ensures a better and more consistent growth of the mycelium, which results in a consistent product quality. This preferred embodiment can relate to fibers with a length of between 1 and 20 cm, preferably between 2 and 15 cm, more preferably between 2.5 and 12.5 cm, even more preferably between 5.0 and 10.0 cm, such as for example between 6.0 and 9.0 cm, or 7.0 and 8.0 cm.

[0045] By using shorter hemp fibers in the growing substrate, the structure of the substrate is improved, allowing the mycelium to spread and develop better. This leads to a more uniform distribution of the mycelium in the substrate, which in turn results in a more homogeneous final product.

[0046] Additionally, this preferred embodiment makes it possible to achieve a higher density of the mycelium, which contributes to the mechanical strength and thermal insulation properties of the produced insulation panels. The use of shorter fibers can also contribute to a faster growth cycle of the mycelium, thereby shortening the total production time.

[0047] In another preferred embodiment, the length of the hemp fibers can be adjusted depending on the specific application and desired properties of the insulation panels. For applications where higher mechanical strength is required, slightly longer fibers can be used, for example between 5 and 20 cm. For applications where higher thermal insulation is desired, shorter fibers can be used, for example between 2 and 10 mm.

[0048] The choice of the length of the hemp fibers can also depend on the availability and cost of the material. Shorter fibers are often a byproduct of hemp processing and can therefore be more cost-effective. Moreover, the use of shorter fibers can contribute to a more sustainable production because residual material from hemp processing is utilized efficiently. In a preferred embodiment, the substrate comprises longer hemp fibers. These longer hemp fibers result in greater structural integrity of the mycelium-based insulation panel. The use of longer hemp fibers in the substrate offers multiple advantages. Firstly, these fibers provide better binding and reinforcement of the mycelium, which leads to a more robust final product. This is especially advantageous in applications where mechanical strength and durability are of crucial importance.

[0049] Preferably, the length of the hemp fibers in the substrate varies between 5 and 50 cm, more preferably between 10 and 40 cm, even more preferably between 15 and 35 cm, and most preferably between 20 and 30 cm. These variations in fiber length offer flexibility in adapting the structural properties of the insulation panel to specific requirements.

[0050] Additionally, the substrate can preferably contain a mixture of hemp shives and hemp fibers, wherein the ratio of shives to fibers can vary. Preferred ratios include, for example, a ratio of 70:30, 60:40, 50:50, or 40:60. These ratios offer the possibility to adjust the balance between structural integrity and other properties such as insulation value and weight. Preferably, however, a ratio is chosen in which shives constitute the main component in terms of wt%, e.g., at least 70 wt%, 75 wt%, 80 wt%, 85 wt%, 90 wt% or more.

[0051] In a preferred embodiment, the length of hemp shives is optimized to promote improved aeration and increased mycelium growth, which leads to the effective production of better- performing insulation panels. The length of the hemp shives can preferably vary between 2 and 50 mm, more preferably between 2.5 and 40 mm, even more preferably between 3 and 30 mm, even more preferably between 4 and 20 mm, and most preferably between 5 and 15 mm, such as for example between 6 and 14 mm, 7 and 13 mm, 8 and 12 mm, 9 and 11 mm, or around 10 mm. This optimization contributes to a better distribution of the growing substrate, allowing the mycelium to feed and grow more efficiently.

[0052] Preferably, at least 50%, more preferably at least 75% (and even more preferably at least 85%, 90%, 95% or more) of the hemp shives (in terms of wt%) are within the above-mentioned ranges.

[0053] By keeping the length of the hemp shives within these preferred ranges, a substrate with an optimal structure that promotes aeration is created. This results in an increased oxygen supply to the mycelium, which is essential for its growth and development. Good aeration also reduces the chance of anaerobic conditions that can hinder the growth of the mycelium and adversely affect the quality of the insulation panels.

[0054] Furthermore, the choice of the length of the hemp shives can also influence the mechanical properties of the final insulation panels. Shorter shives, for example, can contribute to a higher density and strength of the panels, while longer shives can improve flexibility and insulating properties.

[0055] In a possible embodiment, the method comprises the use of longer hemp shives, wherein the length is a minimum of 2 cm, or even a minimum of 3 cm, and even a minimum of 4 or 5 cm or more. The use of longer hemp shives results in a better bond with the mycelium, which leads to greater structural integrity and strength of the insulation panels. Due to the longer shives, the mycelium can adhere and spread better, which contributes to a more consistent and durable structure of the final product.

[0056] Preferably, the hemp shives are evenly distributed throughout the growing substrate to promote uniform growth of the mycelium. This ensures that the mycelium can optimally feed and develop, resulting in a more homogeneous insulation panel.

[0057] More preferably, the growing substrate is prepared by mixing the hemp shives with other organic materials that can support the growth of the mycelium. This can, for example, comprise compost or other plant residues, which together with the hemp shives form a nutritious base for the mycelium.

[0058] Preferably, the substrate is inoculated with a basidiomycete strain known for its efficient growth and strong binding properties. This strain is selected based on its ability to grow quickly and effectively under the given temperature and humidity conditions.

[0059] In a preferred embodiment, the harvested and dried mycelium has a bulk density between 50 and 200 kg / m3, preferably between 70 and 150 kg / m3, and more preferably between 90 and 110 kg / m3. In a preferred embodiment, the hemp mixture comprises fermented hemp, wherein the hemp, after original harvesting (from the field), is packed in bales, after which fermentation is allowed, before further processing into the growing substrate. This has the advantage that sterilization is no longer necessary, and also that the mycelium can grow faster on it.

[0060] In a preferred embodiment, the growing substrate is provided in a mold or container, wherein the mold or container is provided with a paper layer before the growing substrate is provided therein. This ensures a smooth surface of the harvested mycelium, simplifies demolding, and also contributes to the structural integrity and improves characteristics of the mycelium, such as fire resistance and moisture resistance.

[0061] The harvesting of the mycelium preferably occurs after certain desired values have been reached, such as the density and strength of the mycelium. After harvesting, the mycelium is preferably dried to a moisture content of at most 15%, more preferably at most 10%, even more preferably at most 7%, and most preferably at most 5%. This drying process helps to stabilize the final product and to improve the durability and insulating properties of the panel. Furthermore, the drying process also ensures that the mycelium is killed.

[0062] In a possible embodiment, the hemp mixture comprises a mix of shives and / or fibers, wherein the mixture consists mainly of shives. Preferably, the hemp mixture contains between 60% and 80% shives and between 20% and 40% fibers, such as for example between 65% and 75% shives and between 25% and 35% fibers, or between 68% and 72% shives and between 28% and 32% fibers, or even about 70% shives and about 30% fibers.

[0063] In another preferred embodiment, the growing substrate mainly comprises hemp shives, namely at least 70%, or even at least 75%, 80%, 85%, or 90%.

[0064] By using this specific mixing ratio of hemp shives and fibers, the produced insulation panels exhibit improved insulation properties. This results in potential energy savings and improved thermal efficiency. The shives provide a sturdy structure and a high insulating capacity, while the fibers contribute to the cohesion and flexibility of the panel. This achieves an optimal balance between stiffness and flexibility, resulting in an insulation panel that not only has excellent thermal properties but is also mechanically robust. The fibers and shives, which after mechanical reduction have a mutually different length profile (typically shives being shorter than the fibers), ensure a good overall mix, wherein the longer fibers and shorter shives provide a good density of the growing substrate, and also a good energetic (nutritional value) density for the growth of the mycelium.

[0065] In another preferred embodiment, the hemp mixture is first treated to remove any impurities before it is used as a growing substrate for the mycelium. This can be done, for example, by washing and drying the hemp mixture. Preferably, the hemp mixture is washed with water at a temperature between 20°C and 40°C, more preferably between 25°C and 35°C, and most preferably at about 30°C. After washing, the hemp mixture is dried to a moisture content of at most 15%, more preferably at most 12%, even more preferably at most 10%, and most preferably at most 8%.

[0066] Through this pretreatment, the quality of the growing substrate is improved, resulting in faster and more uniform growth of the mycelium. This contributes to the consistency and quality of the final insulation panels. Moreover, a cleaner substrate can reduce the risk of contamination by unwanted microorganisms, which further improves the durability and effectiveness of the insulation panels.

[0067] In another preferred embodiment, the basidiomycetes are a member of the group consisting of Ganoderma, Pleurotus, and Lentinula.

[0068] In another preferred embodiment, the growing substrate is sterilized by means of steam sterilization or microwave sterilization or RF sterilization.

[0069] In another preferred embodiment, the basidiomycete-inoculated substrate is evenly distributed over the growing substrate.

[0070] In another preferred embodiment, the method further comprises a step of compressing the mycelium after harvesting.

[0071] In another preferred embodiment, the growing substrate is prepared by thoroughly mixing the hemp shives and hemp fibers before the basidiomycete-inoculated substrate is added. This mixing process can optionally be performed at a temperature between 18 and 22°C and a relative humidity of 50 to 70%. More preferably, the mixing process is performed at a temperature between 19 and 21°C and a relative humidity of 55 to 65%, even more preferably at a temperature of about 20°C and a relative humidity of about 60%.

[0072] In a preferred embodiment, the mycelium is grown for a period of 7 to 14 days. More preferably, the mycelium is grown for a period of 8 to 12 days, even more preferably for a period of 9 to 11 days, and most preferably for about 10 days. During this growth period, the temperature is preferably maintained between 20 and 27°C, more preferably between 21 and 26°C, even more preferably between 22 and 25°C, and most preferably between 23 and 24°C. The relative humidity is preferably maintained at at least 60%, more preferably between 65% and 75%, even more preferably between 68% and 72%, and most preferably around 70%.

[0073] In another preferred embodiment, the mycelium (and growing substrate) is grown at a moisture content of 80% or less, more preferably 75% or less, even more preferably 70% or less. Typically, the mycelium (and growing substrate) comprises at least 50% moisture during growth, or even 55%, 60% or 65%. After harvesting, the mycelium is dried to a moisture content of at most 15%, more preferably at most 12%, even more preferably at most 10%, and most preferably at most 8%.

[0074] In a preferred embodiment, the growing substrate comprises flour. The addition of flour to the growing substrate promotes faster growth of the mycelium. The flour can preferably be mixed with the hemp substrate to obtain a homogeneous mixture. The flour is provided in a wt% of at most 5%, preferably at most 4%, 3%, 2%, 2.5%, 2%, 1.5%. The flour is provided in a wt% of at least 0.1%, preferably at least 0.2%, 0.4%, 0.5%, or 0.75%. Most preferably, the growing substrate comprises about 1 wt% of flour.

[0075] In another preferred embodiment, the flour can be a wheat flour, although other types of flour such as corn flour, rice flour, or soy flour may also be suitable. The choice of flour can be tailored to the specific growth requirements of the mycelium and the desired properties of the final product.

[0076] In another preferred embodiment, the flour can be sterilized prior to inoculation to eliminate unwanted microorganisms that could hinder the growth of the mycelium. This can be achieved by heating the flour to a temperature between 80°C and 120°C for a period of 30 minutes to 2 hours, more preferably between 90°C and 110°C for 45 minutes to 1.5 hours, and most preferably at 100°C for 1 hour.

[0077] In another preferred embodiment, the flour can be mixed with water to obtain a paste-like consistency before being added to the hemp substrate. This can help to distribute the flour evenly throughout the substrate and improve the availability of nutrients for the mycelium.

[0078] The addition of flour to the growing substrate offers considerable advantages by accelerating the growth of the mycelium, which leads to a shorter production time and a more efficient production process for the insulation panels. Furthermore, the use of flour as an additive can improve the overall quality and performance of the resulting insulation panels.

[0079] In another preferred embodiment, the growing substrate can be enriched with additional nutrients or additives to promote the growth of the mycelium and to improve the properties of the final product. These additives may, for example, comprise minerals or organic compounds that are specifically tailored to the needs of the basidiomycete strain used. This approach allows the method to be adapted to different applications and specifications, enabling the production of a wide range of insulation panels that meet various requirements and standards.

[0080] These supplemental nutrients may, for example, be sugar-containing substances (dispersed or in discrete portions), such as agar, nitrogen sources, phosphorus sources, or other micronutrients. Such additions, particularly in discrete form, can create local variations, such as cavities, changes in density, etc.

[0081] In a preferred embodiment, the method uses hemp fibers as the main component of the growing substrate. Hemp fibers are an environmentally friendly choice due to their renewable nature and low environmental impact during cultivation and processing. These fibers can preferably be mixed with other natural materials to create an optimal growing medium for the mycelium. The use of hemp fibers in the growing substrate contributes to the sustainability of the final product, resulting in insulation panels that are both ecologically responsible and effective.

[0082] In a preferred embodiment, the growing substrate comprises between 60 and 85 wt% cellulose, preferably between 65 and 80 wt%, and more preferably between 70 and 75 wt%. The growing substrate therein comprises between 10 and 32 wt% hemicellulose, preferably between 14 and 28 wt%, and more preferably between 18 and 24 wt%. Additionally, the growing substrate comprises between 1 and 10 wt% lignin, preferably between 2 and 8 wt%, and more preferably between 3 and 6 wt%.

[0083] In a preferred embodiment, the inoculated substrate is added to the growing substrate in a weight ratio between 1:25 and 1:2, preferably between 1 :20 and 1:5, more preferably between 1 : 15 and 1 :8, and even more preferably between 1: 12 and 1:9, such as, for example, 1 : 10.

[0084] In another preferred embodiment, the hemp substrate can be pre-treated to make the nutrients more available to the mycelium. This can be done, for example, by pasteurizing or sterilizing the substrate before it is inoculated with basidiomycetes. This pre-treatment can improve the growth rate and the final quality of the mycelium panel. Moreover, adding extra nutrients to the substrate can promote the growth of the mycelium and further improve the insulating properties of the final product.

[0085] In another preferred embodiment, the mycelium can be exposed to specific environmental factors, such as light or air currents, during the growth process to optimize the structure and properties of the panel. These controlled growth conditions can contribute to a uniform and consistent production of insulation panels with superior properties. By combining these various preferred embodiments, a wide range of insulation panels can be produced that meet different requirements and specifications.

[0086] In a preferred embodiment, the panels have a more consistent quality due to a uniform distribution of nutrients in the substrate. This can be achieved by carefully mixing the substrate before it is inoculated with the basidiomycetes. Mixing the substrate ensures that the nutrients are distributed uniformly, which results in uniform growth of the mycelium. This prevents the formation of weak spots in the insulation material and yields a homogeneous final product.

[0087] Nutrients in the substrate can, for example, consist of organic material such as cellulose or lignin, which are essential for the growth of the mycelium. By distributing these nutrients uniformly, the mycelium can feed and grow more efficiently, which contributes to a stable and consistent final product. In yet another preferred embodiment, the drying step of the mycelium can be carried out under controlled conditions to accurately achieve and maintain the desired moisture content. This can be achieved, for example, by using advanced drying techniques such as vacuum drying or freeze-drying, which can help to preserve the structural integrity and the physical properties of the mycelium.

[0088] In a preferred embodiment, the method comprises artificially introducing cavities into the mycelium substrate during the growth process. By creating these cavities, the aeration of the substrate can be improved, resulting in accelerated growth of the mycelium. This is because the increased air circulation within the substrate provides a more favorable environment for mycelium growth, thereby increasing the growth rate.

[0089] Preferably, the cavities can be introduced by means of mechanical methods, such as the use of air injectors or other equipment that can blow air into the substrate. More preferably, the cavities can have a diameter between 1 and 10 mm, more preferably between 1.5 and 8 mm, more preferably between 2 and 6 mm, and most preferably between 2.5 and 4 mm. These specifications ensure that the cavities are large enough to improve air circulation without compromising the structural integrity of the substrate.

[0090] In another preferred embodiment, the distribution of the cavities within the substrate can be uniform, meaning that the cavities are distributed evenly throughout the entire substrate. This uniform distribution ensures that the air circulation is consistent and that the mycelium can grow uniformly. Alternatively, the cavities can be introduced in specific patterns, depending on the desired growth dynamics and the specific application of the insulation panels.

[0091] Preferably, the cavities are introduced by providing specific components in the growing substrate, which dissolve faster or slower (under the influence of the mycelium). Typically, these are sugar-containing volumes, such as agar jelly, which serve as a nutrient source for the mycelium and are thereby rapidly digested, but thus create "air bubbles" in the mycelium panel that has grown in the meantime. These cavities typically have a diameter between 1 and 10 mm, more preferably between 1.5 and 8 mm, more preferably between 2 and 6 mm, and most preferably between 2.5 and 4 mm. Most preferably, the cavities are introduced by providing rods or tubes through a frame or mold in which the mycelium grows. These rods or tubes preferably, but not necessarily, extend through the entire frame (i.e., from a first side to an opposing side), and thus form cavities in the final mycelium panel, along which moisture can escape from the core of the panel during drying. This is particularly useful in drying processes that use RF or microwave radiation.

[0092] Additionally, this offers the advantage that in this way, channels are also available in the panel for passing (technical) conduits, so that these no longer have to be installed at the time of use. Additionally, they can also be used for connecting panels to each other.

[0093] Preferably, the cavities are elongated and parallel to a front and rear face of the panel, and extend in the width or depth, more preferably substantially centrally, so as to optimally remove moisture from the core of the panel and also to optimize the strength of the panel.

[0094] The tubes or rods are thus provided parallel to the front face / rear face of the panel.

[0095] It is self-evident that the tubes or rods can alternatively or additionally extend transversely to the front face / rear face. The tubes or rods can also extend only partially through the panel, thus forming hollows or pits.

[0096] Preferably, the tubes or rods are provided in an ordered pattern, at mutually equal distances, wherein the tubes or rods have a substantially equal diameter. The distance between neighboring rods or tubes (and thus cavities) is typically between 2 cm and 50 cm, preferably between 3 cm and 35 cm, more preferably between 4 cm and 25 cm, even more preferably between 5 cm and 20 cm, even more preferably between 6 cm and 15 cm, and even more preferably between 7 cm and 12 cm or between 7.5 cm and 10 cm.

[0097] Preferably, the rods or tubes (and thus the cavities) have a diameter between 5 mm and 80 mm, preferably between 8 mm and 60 mm, even more preferably between 10 mm and 50 mm, even more preferably between 12 mm and 40 mm, even more preferably between 16 mm and 35 mm, even more preferably between 20 mm and 30 mm, and even more preferably between 22 mm and 26 mm.

[0098] For thick panels, tubes and rods can be chosen that are provided in multiple planes parallel to the front face / rear face, but in most cases, a single plane with cavities will be used. Ideally, a mold or frame is used wherein the tubes or rods are already present in the mold or frame, and the mycelium thus grows around them (wherein a part of the mold is removable together with the tubes or rods to remove the panel). Alternatively, the tubes or rods can also be installed later, during or even after the growth. Thus, the mold or frame can be provided with through-openings in the frame that forms the mold or frame, into which the tubes or rods can be slid, and removed again at the moment the panel is demolded.

[0099] Preferably, the temperature during the growth process can range between 15 and 30°C, more preferably between 18 and 28°C, more preferably between 20 and 27°C, more preferably between 21 and 26°C, and most preferably between 22 and 25°C. The relative humidity can preferably range between 50 and 80%, more preferably between 55 and 75%, more preferably between 60 and 70%, and most preferably between 60 and 65%. By accurately controlling these parameters, an optimal environment for mycelium growth can be created, which contributes to the efficiency of the production process.

[0100] In another preferred embodiment, the drying of the mycelium after harvesting can be carried out at a temperature between 80 and 200°C, more preferably between 90 and 160°C, more preferably between 55 and 65°C, and most preferably between 100 and 120°C. This ensures that the moisture content of the mycelium is reduced to at most 10%, more preferably at most 8%, more preferably at most 6%, and most preferably at most 5%. This makes the insulation panels more stable and durable.

[0101] In a preferred embodiment, the harvested mycelium undergoes the drying step for at least 2 hours, preferably at least 3 or even 4 hours, typically until a desired moisture content is reached. This can be done, for example, using a convection oven, although alternatives exist, as discussed below.

[0102] In a preferred embodiment, the method comprises drying the harvested mycelium using microwave radiation. This drying with microwave radiation significantly shortens the drying time. The drying of the mycelium can, for example, take place at a power between 500 and 1000 watts, preferably between 600 and 900 watts, more preferably between 700 and 850 watts, and even more preferably between 750 and 800 watts. The drying time can vary depending on the power and the amount of mycelium, but is preferably between 5 and 20 minutes, more preferably between 7 and 15 minutes, even more preferably between 8 and 12 minutes, and most preferably around 10 minutes.

[0103] Note that the use of microwave radiation is preferably supplemental to (and more preferably prior to) the drying process with a convection oven. The advantage of this is, among other things, that the mycelium is also completely deactivated (killed) by the microwave radiation.

[0104] Drying with microwave radiation can also contribute to the uniformity of the moisture content in the dried mycelium through more uniform heat generation in the material (whereas convection generates heat from the outside in), which results in a more consistent final product, partly because overheating on the outside, which can lead to cracking, is avoided. Moreover, this technique is substantially faster, more sustainable (less energy required), and cheaper than convection drying. This is especially advantageous when the moisture content of the dried mycelium is reduced to at most 10%, preferably at most 8%, more preferably at most 6%, and most preferably at most 5%.

[0105] In certain embodiments, the drying process is carried out solely by means of microwave radiation.

[0106] In an alternative preferred embodiment, the drying with microwave radiation can be performed in a batch process or a continuous process. In a batch process, a certain amount of mycelium is dried at once, whereas in a continuous process, the mycelium is fed through a microwave drying installation. Both methods have their own advantages; a batch process can be easier to control, while a continuous process can be more efficient for larger volumes.

[0107] The use of microwave radiation for drying the mycelium thus offers significant advantages in terms of drying time and product consistency, making it a preferred embodiment within the method for producing insulation panels that consist of mycelium.

[0108] Alternatively (or even sequentially supplementally), the drying can also be done by means of radio-frequency radiation. Preferably, the drying by means of RF radiation is supplemental (following or preceding) to the drying via a convection oven, with the advantage that the mycelium is deactivated in the RF step. Additionally, RF drying also has the advantage that the heat is generated uniformly inside the material, in contrast to, e.g., convection heating, where it heats from the outside in. This leads to a more uniform moisture content and a better final product, partly because overheating on the outside, which can lead to cracking, is avoided. Moreover, this technique is substantially faster than convection drying.

[0109] RF radiation, but also microwave radiation to a lesser extent, is particularly useful for thicker panels, where conventional drying processes have much more difficulty reaching moisture in the core. Thus, panels with a thickness from 5 cm, but in particular from 7.5 cm or 10 cm and more (such as typical insulation panels), are dried much more efficiently (both in terms of speed and energy efficiency) with the aid of RF or microwave radiation.

[0110] Preferably, the step of drying the harvested mycelium comprises an RF drying step, wherein the insulation panel is dried by means of radio-frequency (RF) radiation with a frequency between 5 MHz and 100 MHz, wherein during drying with the RF radiation, the harvested mycelium is killed.

[0111] Preferably, the RF radiation is provided by means of one or more RF emitters. By providing these at a suitable distance from the panel, a balance can be found between efficient drying and not overheating the surface. Preferably, a minimum distance of 50 mm is used, more preferably 60 mm, 70 mm, or even 80 mm. Preferably, a maximum distance of 200 mm is used, more preferably 175 mm, 150 mm, 130 mm, 120 mm, or less.

[0112] Prior to drying, perforations can also be made in the panel (or these may already be present), along which water can evaporate from the core. The perforations may or may not extend completely through the panel. Preferably, the perforations run parallel to the front face / rear face, but they can also or additionally run through the front face / rear face. Particularly in the case of incomplete perforations (not completely through the panel), these are preferably perpendicular to the front face / rear face.

[0113] RF radiation typically has a frequency between 1 and 300 MHz, but a frequency between 5 and 100 MHz is preferably chosen, and more preferably between 10 and 50 MHz, such as, for example, between 12.5 and 30 MHz.

[0114] Preferably, the RF irradiation of the panels lasts at least 10 minutes, but preferably substantially longer to achieve a desired maximum moisture content, for example, at least 15 minutes, 20 minutes, 25 minutes, or even 30 minutes. In some variations, the panels were dried with RF radiation in multiple, shorter cycles, which allows the still-present moisture in the panels to redistribute, to permit better drying in a subsequent cycle. The cycles preferably each last at least 5 or 10 minutes, and preferably even longer, such as for example 15 minutes, 20 minutes, 30 minutes, etc. Herein, the panel can also be turned over between cycles.

[0115] Preferably, the RF drying step is performed at an average power of at least 0.10 kW, preferably at least 0.15 kW, per kilogram of the insulation panel. More preferably, this power-to-mass ratio is at least 0.20 kW / kg, 0.25 kW / kg, or more.

[0116] Preferably, the RF drying step is performed at an average power of at most 5 kW, preferably at most 4 kW, per kilogram of the insulation panel. More preferably, this power-to-mass ratio is at most 3 kW / kg, 2 kW / kg, or less, such as, for example, 1.5 kW / kg, 1.0 kW / kg, 0.75 kW / kg, 0.5 kW / kg.

[0117] The heating by means of RF radiation can in some applications also be carried out for a very short duration, for example solely for deactivating the mycelium. For example, this can be done for at most 30 seconds, or at most 1 minute, 2 minutes, 5 minutes, 10 minutes, etc. The applicant noted, however, that a minimum period of 1 minute was recommended for killing the mycelium. Longer periods, in turn, contributed to a more uniform moisture content, especially in combination with convection drying.

[0118] The heating via RF typically led to a warming to approximately 100°C, although higher temperatures are possible.

[0119] In certain embodiments, the drying process is carried out solely by means of radiofrequency radiation.

[0120] In a preferred embodiment, the method comprises a step of sterilizing the growing substrate before the mycelium is inoculated. This step significantly minimizes the risk of contamination, which leads to a more reliable and more uniform production process for the insulation panels. The sterilization can preferably be carried out by exposing the substrate to a temperature between 50 and 90°C, more preferably between 60 and 80°C, even more preferably at least 70°C. Alternatively, the sterilization can also be achieved by sterilizing the substrate under a pressure of 1 to 3 bar, more preferably between 1.5 and 2.5 bar, even more preferably between 1.8 and 2.2 bar, and most preferably at approximately 2 bar. Preferably, this sterilization step lasts at least 1 hour, more preferably at least 2 hours.

[0121] In an alternative embodiment, the growing substrate is sterilized prior to being placed in the mold or in the receptacle and prior to placing the basidiomycete-inoculated substrate in and / or on the growing substrate. The sterilization thereby takes place under a minimum pressure of 5 psi, preferably of 10 psi, and at a minimum temperature of 80°C, preferably of 100°C, and more preferably of 115°C.

[0122] The sterilization step can preferably have a duration of 30 to 90 minutes, more preferably between 40 and 80 minutes, even more preferably between 50 and 70 minutes, and most preferably about 60 minutes. By implementing this sterilization step, the chance of competition from unwanted microorganisms is reduced, which results in a more efficient use of the growing substrate by the mycelium. This contributes to a higher quality and consistency of the produced insulation panels.

[0123] In another preferred embodiment, the sterilization can be combined with a pasteurization process, wherein the substrate is first pasteurized at a temperature of 60 to 90°C, more preferably between 65 and 85°C, even more preferably between 70 and 80°C, and most preferably at about 75°C. This combination of sterilization and pasteurization ensures an even greater reduction of possible contaminants, which further increases the reliability of the production process. Moreover, this approach can lead to a faster colonization of the substrate by the mycelium, which can shorten the total production time of the insulation panels.

[0124] By including this sterilization step in the method, it becomes possible to produce insulation panels with a consistently high quality, which offers a significant advantage over existing methods. The use of hemp as a growing substrate in combination with a basidiomycete-inoculated substrate and the described sterilization step results in an innovative and reliable production process for sustainable insulation panels.

[0125] In another preferred embodiment, the insulation panels can be treated with natural fire retardants to increase fire safety. This can be achieved, for example, by adding fire-retardant substances to the growing substrate or by a surface treatment of the finished panels. In a possible embodiment, the panels are further treated with a coating, preferably a natural tree resin extract, preferably from conifers. This provides an additional seal (against moisture) for the panel.

[0126] In a further embodiment, the mycelium panel is further processed into a pressed panel that can serve as an alternative to, e.g., gypsum board. For this purpose, the method comprises an additional step of pressing the panel to obtain a desired density. The pressing step is carried out at a minimum pressure of 1000 kN / m2, preferably 1500 kN / m2, more preferably 2000 kN / m2or even 2500 kN / m2. Most preferably, this is a minimum of 3000 kN / m2or even more, such as 4000, 5000, 6000, 8000, 10,000 kN / m2or more.

[0127] This step is more preferably carried out with a so-called heat press, at a minimum temperature of 120°C, preferably 130°C, more preferably 140°C, even more preferably 150°C, even more preferably 160°C, even more preferably 170°C, or even 180°C or more, such as 190°C, 200°C, etc.

[0128] The step of (heat) pressing typically lasts between 5 and 30 minutes, preferably between 7.5 and 20 minutes, such as 10 or 15 minutes.

[0129] This results in pressed panels with a final density between 350 and 700 kg / m3, preferably between 400 and 600 kg / m3, more preferably between 450 and 550 kg / m3.

[0130] In a possible embodiment, the growing substrate comprises additional non-organic components in order to modify the physical and chemical characteristics according to the application.

[0131] These non-organic components can, for example, relate to or comprise perlite, which is a naturally occurring volcanic glass that is formed when lava cools rapidly and traps water. It is mainly used in horticulture, construction, and industry because of its unique properties. Perlite has very good thermal and acoustic properties, and is also very light. Additionally, it can also be expanded at high temperatures to a multiple of its original volume, thereby creating a foam-like structure.

[0132] Perlite can be present in the growing substrate with a weight percentage of at least 5%, preferably at least 10%, 15% or even 20%, such as, for example, at least 25%, 30%, 35% to even 40%. Preferably, the weight percentage of perlite is limited to 50% or even 45% or 40%.

[0133] The perlite is added in granules with a diameter between 1 and 10 mm, preferably between 1.5 and 7 mm, and more preferably between 2 and 4 mm. Preferably, the perlite is mixed with a water and sugar solution (at least 200% of the weight of the perlite, wherein the solution is 5% sugar) before sterilization, and then mixed into the substrate.

[0134] Advantages of the perlite are that this improves the fire resistance and insulation values of the panel.

[0135] Another or an additional component can be latex and / or polyurethane foam. This offers, among other things, the advantage that it is available simply and inexpensively through recycling.

[0136] The latex and / or PU foam can be present in the growing substrate with a weight percentage of at least 5%, preferably at least 10%, 15%, 20% or even 25%, such as for example at least 30%, 35%, 40%, 45% to even 50%. Preferably, the weight percentage of latex / PU foam is limited to 60% or even 55% or 50%.

[0137] The latex and / or PU foam is added in pieces with a diameter between 5 and 30 mm, preferably between 10 and 15 mm.

[0138] Preferably, it is mixed with a water and sugar solution (at least 200% of the weight of the latex / PU foam, wherein the solution is 5% sugar) before sterilization, and then mixed into the substrate.

[0139] Both the perlite and the latex / PU foam contribute to improved acoustic performance of the panels. The perlite achieves this through its porous structure and resulting sound absorption, while latex and PU foam achieve this through their elastic characteristics which provide for damping of sound.

[0140] The invention according to the second aspect relates to panels manufactured according to the methods of the first aspect, in all possible variations, wherein the above-mentioned advantages are applicable.

[0141] EXAMPLES

[0142] The present invention will now be further illustrated by means of the following examples. The present invention is in no way limited to the given examples or to the embodiments presented in the figures.

[0143] A growing substrate consisting of 80% hemp shives and 20% hemp fibers was sterilized at a temperature of 115°C and a pressure of 10 psi for 30 minutes. After sterilization, the substrate was inoculated with a basidiomycete-inoculated substrate of the genus Ganoderma. The mycelium was grown for a period of 10 days at a temperature of 25°C and a relative humidity of 70%. After reaching the desired growth parameters, the mycelium was harvested and dried to a moisture content of 5% using microwave radiation. This resulted in an insulation panel with improved thermal insulation and increased durability.

[0144] Example 2

[0145] A growing substrate consisting of 75% hemp shives with a maximum length of 2.0 cm and 25% hemp fibers with a maximum length of 10 cm was sterilized at a temperature of 100°C and a pressure of 5 psi for 20 minutes. The substrate was then mixed with flour in a weight percentage of 1.0% relative to the moist growing substrate. The inoculated substrate was added and the mycelium was grown at a temperature of 22°C and a relative humidity of 65% for 12 days. After harvesting, the mycelium was dried to a moisture content of 8% using air circulation. The resulting insulation panels showed improved insulation performance and faster mycelium growth.

[0146] Example 3

[0147] A growing substrate consisting of 85% hemp fibers and 15% hemp shives was sterilized and then inoculated with a basidiomycete-inoculated substrate. The mixture was poured into a mold and a first hemp-based panel was placed on top of the mixture. The mycelium was grown at a temperature of 24°C and a relative humidity of 75% for 15 days. After reaching the predetermined parameters, the mycelium was harvested and dried to a moisture content of 5%. This resulted in an insulation panel with improved structural integrity and increased durability.

[0148] Example 4

[0149] A growing substrate consisting of a mixture of hemp shives and hemp fibers in a weight ratio of 3: 1 was sterilized at a temperature of 110°C and a pressure of 8 psi for 25 minutes. The inoculated substrate was added and the mycelium was grown at a temperature of 80C and a relative humidity of 14% for 26° days. During growth, cavities were artificially introduced into the mycelium. After harvesting, the mycelium was dried to a moisture content of 6% using microwave radiation. The insulation panels showed accelerated production and improved insulation performance.

[0150] Example 5 A growing substrate consisting of 70% hemp shives and 30% hemp fibers was sterilized and mixed with basidiomycete-inoculated sawdust at a percentage of 7.5%. The mixture was poured into a receptacle and the mycelium was grown at a temperature of 23°C and a relative humidity of 70% for 11 days. After harvesting, the mycelium was dried to a moisture content of 7% using air circulation. The resulting insulation panels were environmentally friendly and showed improved mycelium growth and consistency in product quality.

[0151] Example 6

[0152] A panel obtained from Example 5 was then further processed, and underwent a heat press step at a temperature of 180°C with a pressure of 400 kN / m2for 10 minutes. This resulted in a pressed panel with a density of 525 kg / m3, which was then tested for thermal conductivity and showed a lambda value of 0.051 W / (m-K).

[0153] It is assumed that the present invention is not limited to any embodiment previously described and that certain modifications may be made to the presented manufacturing example without departing from the scope of the appended claims. The present invention is, for example, described with reference to the use of substrates based on hemp and mycelium, but it is clear that the invention can, for example, be applied to other organic substrates or fungal species or to different sterilization methods.

[0154] The present invention is by no means limited to the embodiments described in the examples. On the contrary, methods according to the present invention can be realized in many different ways without departing from the scope of the invention.

Claims

CLAIMS1. A method for producing an insulation panel that substantially consists of mycelium, comprising the following steps: a. providing a growing substrate for the mycelium to grow on in a receptacle or mold, wherein the growing substrate has been previously sterilized; b. providing a basidiomycete-inoculated substrate in and / or on the growing substrate; c. growing mycelium of the basidiomycetes in / on the growing substrate for a minimum predetermined time, wherein the temperature is substantially between 20°C and 27°C, and wherein the relative humidity is at least 60%; d. monitoring predetermined parameters of the mycelium; e. harvesting the mycelium when the predetermined parameters meet predetermined threshold values; f. drying the harvested mycelium to a moisture content below 10%, wherein the step of drying the harvested mycelium comprises an RF drying step, wherein the insulation panel is dried by means of radiofrequency (RF) radiation with a frequency between 5 MHz and 100 MHz, wherein during the drying with the RF radiation, the harvested mycelium is killed.

2. The method according to the preceding claim 1, wherein the growing substrate consists of at least 70%, and preferably at least 80%, hemp shives.

3. The method according to the preceding claim 1 or 2, wherein the growing substrate comprises hemp fibers, and wherein the hemp fibers have a maximum length of 15 cm, preferably of 10 cm, for at least 95% of the hemp fibers.

4. The method according to the preceding claim 3, wherein at least 50%, preferably at least 75%, of the hemp fibers have a minimum length of 1.0 cm, preferably a minimum of 2.5 cm and more preferably a minimum of 5.0 cm.

5. The method according to any of the preceding claims 2 to 4, wherein the hemp shives have a maximum length of 2.5 cm, preferably 2.0 cm and morepreferably 1.5 cm, for at least 90%, preferably at least 95%, of the hemp shives.

6. The method according to any of the preceding claims 2 to 5, wherein at least 50%, preferably at least 75%, of the hemp shives have a minimum length of 0.25 cm, preferably a minimum of 0.35 cm and more preferably a minimum of 0.5 cm.

7. The method according to any of the preceding claims 1 to 6, wherein during the growing, one or more spacers are provided through the mold or receptacle, which extend at least partially through the mold or the receptacle, for creating cavities in the mycelium grown in the mold or the receptacle.

8. The method according to the preceding claim 7, wherein the mold or receptacle defines a substantially beam-shaped cavity with a front side and a rear side, wherein the spacers comprise tubes or rods, which extend substantially parallel to the front side and / or the rear side.

9. The method according to any of the preceding claims 1 to 8, wherein a first hemp-based panel is provided in the receptacle or in the mold, wherein the growing substrate and / or the basidiomycete-inoculated substrate is provided directly in the receptacle or the mold on the first hemp-based panel.

10. The method according to the preceding claim 9, wherein a second hemp-based panel is provided in the receptacle or in the mold, wherein the second hempbased panel is provided on top of the growing substrate and the basidiomycete-inoculated substrate.

11. The method according to any of the preceding claims 1 to 10, wherein the RF radiation has a frequency between 10 and 50 MHz.

12. The method according to any of the preceding claims 1 to 11, wherein the growing substrate is sterilized prior to being provided in the mold or in the receptacle and prior to providing the basidiomycete-inoculated substrate in and / or on the growing substrate, wherein the sterilizing takes place under a minimum pressure of 5 psi, preferably of 10 psi, and at a minimum temperature of 80°C, preferably of 100°C, and more preferably of 115°C.

13. The method according to any of the preceding claims 1 to 12, comprising a step of providing non-organic components in the growing substrate for modification of the physical and / or chemical properties of the produced insulation panel, wherein the non-organic components preferably comprise perlite, latex foam and / or polyurethane foam, more preferably in a weight percentage of the growing substrate between 5% and 50%.

14. The method according to any of the preceding claims 1 to 13, comprising a step of heat-pressing the dried mycelium at a temperature of at least 150°C, and a minimum pressure of 2000 kN / m2for a predetermined period of time, preferably at least 5 minutes.

15. The method according to any of the preceding claims 1 to 14, wherein the step of drying the harvested mycelium, performed by means of radiofrequency (RF) radiation, precedes a further drying step, wherein the further drying step preferably comprises convection drying.

16. The method according to any of the preceding claims 1 to 15, wherein the RF drying step comprises at least one cycle of at least 10 minutes, preferably at least 15 minutes.

17. The method according to any of the preceding claims 1 to 16, wherein the RF drying step is performed at an average power of at least 0.10 kW, preferably at least 0.20 kW, per kilogram of the insulation panel.

18. The method according to any of the preceding claims 1 to 17, wherein the RF drying step is performed at an average power of at most 5 kW, preferably at most 3 kW, per kilogram of the insulation panel.