2017 most likely will be a turning point in the implementation of the Energy Union objectives and the 2030 climate and Energy package. Several initiatives are in place as the new Renewable Energy Directive for the period after 2020-2030, an updated EU Bioenergy Sustainability Policy. But do not forget commitments made in the 2015 Paris Agreement.
The Renewable Energy Directive 2009/28/EC
, together with the Biofuels Directive 2003
and the Fuel Quality Directive
, is one of the main pillars of biofuels policy. The Directive set legally binding targets for Member States to fulfil at least 20% of its total energy needs with renewables by 2020.
On November 2016, the European Commission presented a proposal for a revised Renewable Energy Directive within a broader Clean Energy package of proposals. The ultimate goal of the proposal is to increase the share of renewable energy sources in the overall energy mix to at least 27 % by 2030, whilst ensuring that the EU becomes the world leader in renewable energy. This binding target will be fulfilled through individual Member States’ contributions guided by the need to deliver collectively for the EU.
Decarbonisation of transport through development of advanced biofuels
and definition of the role of food-based biofuels
after 2020 are among the main challenges identified by the Commission.The revised Renewable Energy Directive introduces an obligation on European transport fuel suppliers to provide an increasing share of renewable and low-carbon fuels, including advanced biofuels, renewable transport fuels of non-biological origin (e.g. hydrogen), waste-based fuels and renewable electricity. At the same time, to minimize the Indirect Land-Use Change
(ILUC) impacts, introduces a cap on the contribution of food-based biofuels towards the EU renewable energy target, starting at 7% in 2021 and going down progressively to 3.8% in 2030.The revised Renewable Energy Directive also strengthens the existing EU criteria for bioenergy sustainability.
The Commission is committed to make the biomass for energy sustainable, improving sustainability criteria for biofuels, requiring that (new) advanced biofuels emit at least 70% fewer GHG emissions than fossil fuels.
The proposal has been referred to the Parliament’s Industry, Research and Energy Committee, where the work is still at preparatory phase.
During the first 14 months of the project, EXERGY Ltd, in collaboration with the project partners, has been working on the identification and initial assessment of different risks, mainly associated with the commercialisation of the main W2F processes and products (biobutanol) and sub-products (proteins, biogas, etc). The main risks are linked to the fluctuation in prices and availability of the feedstocks as well as the direct competition with other fuels and the impact on the supply chains. These factors, in conjunction with the overall costs of both the pre-treatments and the technology to obtain biobutanol have been identified as important risks to be taken into consideration, highlighting the importance of current work to develop and optimise the W2F processes.
As an initial part of the activities of experimental tests on engines and burners, being part of the tasks in the WP6 (Industrial scale-up), UPM have begun to plan and prepare the test methodology, incuding the quantity and the origin of the butanol to be used in such tests. On the other hand, preliminary tests have been made on CFR engine (variable compression ratio engine) in order to check its behavior and detect trend between using or non-using butanol. Lastly, the supply of butanol and the engines (diesel and spark ignition engines) are being managed.
As part of the WP6, UNIZAR is involved in the study of the pyrolysis and the oxidation of the four differentbutanol isomers, under a wide range of experimental conditions. Experimental results obtained will be used to develop a kinetic model, which allows to describe the processes studied. Additionally, the soot obtained in pyrolysis experiments will be analyzed to determine its toxicity in cooperation with UNINA.
Since the start of the project, TEAGASC has investigated novel green and environmentally friendly extraction technologies to obtain valuable components from food wastes and their fermentation by-products for their valorisation. This task, under the WP5 (Valorisation of high value by-products), has been conducted in close collaboration with WP1. Extractions assisted by microwave, power ultrasound, enzyme, ultra-Turrax, or high pressure technology and their combination were employed. Much higher yield was obtained under the optimal extraction conditions than under conventional extraction conditions and qualities of the extraction products were evaluated.
Under the WP4 (Catalytic convertion of pure ethanol into butanol with an heterogeneous structured catalystic), activities related to the catalytic valorisation of ethanol to 1-butanol have been implemented by IRC-CNR. Bio-ethanol can be catalytically converted into butanol through alcohol dimerization called Guerbet reaction. Basic sites are essential to get Guerbet coupling of alcohol and addition of a metal function gives better dehydrogenation/hydrogenation properties. Powder γ-Al2O3, hydroxyapatite and MgO have been synthesized according to different techniques to obtain high surface area materials. Ruthenium or Nickel have been dispersed on the supports. Textural, acid and basic properties of the three supports and redox properties of the metals have been characterized in order to optimize the catalyst formulation. Ru/MgO and Ni/MgO provided good butanol yields and are the candidates for the preparation of structured catalysts for operation in the pilot-scale rig.
Simultaneously, BGU has been working on two alternative catalytic routes:
i) Catalytic conversion of ethanol-water mixtures produced by waste biomass fermentation to butanol included conversion of ethanol-water mixtures to butylene that further reacts with water yielding butanol.
ii) Catalytic conversion of ethanol-water and aceton-butanol-ethanol (ABE) – water mixtures produced by waste biomass fermentation into biogasoline and hydrocarbon biofuels components boiling out in the temperature range of 30 – 300oC.
In both cases, catalytic materials have been developed and process conditions have been validated.
Under the WP3 (ABE fermentation solvent recovery), TU WIEN conducted activities aimed at recovery and concentration of the butanol mixture produced by fermentation. To this end, TU WIEN investigated pervaporation for product recovery in ABE fermentation. Focus was given to the comparison of different membrane materials near real process conditions. Obtained design parameters are used for modeling and comparing upgrading techniques, to select a suitable process to be coupled to the ABE fermenter.
Activities concerning the WP2 (metabolic engineering for biomass conversion to butanol) have been carried out by WEIZMANN. A library of ligno-cellulolytic enzymes has been developed and a panel of mixtures tested on the four different types of untreated agrowastes. High levels of enzymatic degradation was observed on brewer’s spent grain by a mixture of 3 cellulases, 1 xylanase and 1 bifunctional xylanase-laccase. These five enzymes were attached to scaffoldins to form a designer cellulosomal complex, which was found to be even more efficient than the free enzyme mixture.
After one year of activities, several results have been achieved:
Under the WP1 (selection of renewable feedstock for ABE fermentation), a preliminary analysis has been conducted by ITACYL together with ENCO on agrofood waste, in order to select the most suitable AFWs wastes to be investigated for biobutanol production. The selected agrofood waste (potato peel, apple pomace, brewers’ spent grain and coffee silverskin) have been chemically characterised and a conservation protocol established.
Recently, the selection of the most suitable biomass degradation pre-treatment for the agro-food waste has been carried out with the aim to improve the ABE fermentation. The task has been completed by ITACYL, which has been working in cooperation with IRIS, TOMSA, IRC-CNR, BIOPOX. Different pre-treatment techniques (autohydrolysis, dilute chemical pretreatment, ultrasound pretreatments, microwave pretreatments, deep eutectic solvents and enzymatic pretreatments), in order to determine the optimal methods for hydrolyzation of the cellulose and hemicellulose fractions and to remove and recovery the ligning fraction. The selection of pre-treatment techniques was based on cost- and energy-efficiency criteria; high fermentable sugar yield; low concentration of inhibitory compounds for the subsequent enzymatic hydrolysis and fermentation steps. The pre-treatments have been compared in terms of simple sugars released (glucose, xylose, etc.) and inhibitors generated for the subsequent hydrolysis and fermentation steps.