Review of solar dryers for agricultural products in Asia and Africa : An innovation landscape approach
Udomkun, Patchimaporn ; Romuli, Sebastian ; Schock, Steffen ; Mahayothee, Busarakorn ; Sartas, Murat ; Wossen, Tesfamicheal ; Njukwe, Emmanuel ; Vanlauwe, Bernard ; Müller, Joachim - \ 2020
Journal of Environmental Management 268 (2020). - ISSN 0301-4797
Active dryer - Hybrid dryer - Passive dryer - Renewable energy - Solar drying application - Technology adoption
Solar drying is one of the most efficient and cost-effective, renewable, and sustainable technologies to conserve agricultural products in Asian and sub-Saharan African (SSA) countries. This review paper presents the different types of solar dryers that are widely used in Africa and Asia. In addition, the pre-eminent effects of their use on product quality, as well as their economic, environmental, and social impacts, are highlighted. Since financial, external, and structural factors play a key role in the adoption and scaling of solar dryers, this paper also discusses the impact of these factors on the effectiveness of solar drying technologies in selected Asian and SSA countries.
Advancing the relationship between renewable energy and ecosystem services for landscape planning and design : A literature review
Picchi, Paolo ; Lierop, Martina van; Geneletti, Davide ; Stremke, Sven - \ 2019
Ecosystem Services 35 (2019). - ISSN 2212-0416 - p. 241 - 259.
Ecosystem services - Energy transition - Landscape infrastructure - Landscape planning and design - Renewable energy - Renewable energy technologies
The transition to a low carbon future is starting to affect landscapes around the world. In order for this landscape transformation to be sustainable, renewable energy technologies should not cause critical trade-offs between the provision of energy and that of other ecosystem services such as food production. This literature review advances the body of knowledge on sustainable energy transition with special focus on ecosystem services-based approaches and methods. Two key issues emerge from this review: only one sixth of the published applications on the relation between renewable energy and landscape make use of the ecosystem service framework. Secondly, the applications that do address ecosystem services for landscape planning and design lack efficient methods and spatial reference systems that accommodate both cultural and regulating ecosystem services. Future research efforts should be directed to further advancing the spatial reference systems, the use of participatory mapping and landscape visualizations tools for cultural ecosystem services and the elaboration of landscape design principles.
Ecological intensification by integrating biogas production into nutrient cycling : Modeling the case of Agroecological Symbiosis
Koppelmäki, Kari ; Parviainen, Tuure ; Virkkunen, Elina ; Winquist, Erika ; Schulte, Rogier P.O. ; Helenius, Juha - \ 2019
Agricultural Systems 170 (2019). - ISSN 0308-521X - p. 39 - 48.
Biological nitrogen fixation - Localized agrifood system - Nutrient losses - Organic farming - Renewable energy - Sustainable intensification
There is growing demand to produce both food and renewable energy in a sustainable manner, while avoiding competition between food and energy production. In our study, we investigated the potential of harnessing biogas production into nutrient recycling in an integrated system of organic food production and food processing. We used the case of Agroecological Symbiosis (AES) at Palopuro, which is a combination of three farms, a biogas plant, and a bakery, as a case to explore how biogas production using feedstocks from the farms can be used to improve nutrient cycling, and to calculate how much energy could be produced from the within-system feedstocks. The current system (CS) used in organic farms, and the integrated farm and food processing AES system, were analyzed using Substance Flow analysis. In the AES, annual nitrogen (N) and phosphorus (P) surpluses were projected to be reduced from 95 kg ha−1 to 36 kg ha−1 and from 3.4 kg ha−1 to −0.5 kg ha−1 respectively, compared to the CS. Biogas produced from green manure leys as the major feedstock, produced 2809 MWh a−1. This was 70% more than the energy consumed (1650 MWh a−1) in the systemand thus the AES system turned out to be a net energy producer. Results demonstrated the potential of biogas production to enhance the transition to bioenergy, nutrient recycling, and crop productivity in renewable localized farming and food systems.
Opportunities and risks for -sustainable biomass export from the south-eastern United States to Europe
Fingerman, Kevin R. ; Nabuurs, Gert Jan ; Iriarte, Leire ; Fritsche, Uwe R. ; Staritsky, Igor ; Visser, Lotte ; Mai--Moulin, Thuy ; Junginger, Martin - \ 2019
Biofuels Bioproducts and Biorefining 13 (2019)2. - ISSN 1932-104X - p. 281 - 292.
Bioelectricity - Forest residue - Renewable energy - Sustainable biomass - Trade policy
Import of wood pellets to the EU from the southeastern United States has increased almost ten-fold over the past seven years, driven largely by mandates under the Renewable Energy Directive. While the displacement of fossil fuels with biomass can offer significant energy diversity and climate benefits, these must be balanced against the potential detriment from unsustainable extraction of biomass resources. This study projects the scale of the sustainable biomass resource base in the US southeast through 2030 under various scenarios of industry development and domestic market dynamics. We characterise this resource base at the county level, disaggregating it by material type and spatially constraining it to ensure biodiversity conservation. Our analysis shows that there could be as much as 70 million green metric tons of sustainable export potential from the US Southeast in 2030. However, we also show the extent to which sustainable sourcing criteria applied only to EU biomass energy imports could create leakage across biomass markets, erasing gains from any sustainability mandate. This leakage risk was fairly consistent across our study scenarios and time periods, ranging from 50 to over 63 million green tons of biomass per year. Meaningful biodiversity protections can only be achieved if sustainability criteria for biomass import to the EU are combined with more comprehensive support for sustainable sourcing across biomass industries in exporting regions.
An exploration of the three-layer model including stakeholders, markets and technologies for assessments of residential smart grids
Reinders, Angèle ; übermasser, Stefan ; Sark, Wilfried van; Gercek, Cihan ; Schram, Wouter ; Obinna, Uchechi ; Lehfuss, Felix ; Mierlo, Barbara van; Robledo, Carla ; Wijk, Ad van - \ 2018
Applied Sciences 8 (2018)12. - ISSN 2076-3417
Electricity market - End-users - Energy products and services - Flexibility - Renewable energy - Smart grids - Stakeholders
In this paper, a framework is presented for the evaluation of smart grid environment which is called the three-layer model. This three-layer model comprises three specific categories, or 'layers', namely, the stakeholder, market and technologies layers. Each layer is defined and explored herein, using an extensive literature study regarding their key elements, their descriptions and an overview of the findings from the literature. The assumption behind this study is that a solid understanding of each of the three layers and their interrelations will help in more effective assessment of residential smart grid pilots in order to better design products and services and deploy smart grid technologies in networks. Based on our review, we conclude that, in many studies, social factors associated with smart grid pilots, such as markets, social acceptance, and end-user and stakeholder demands, are most commonly defined as uncertainties and are therefore considered separately from the technical aspects of smart grids. As such, it is recommended that, in future assessments, the stakeholder and market layers should be combined with the technologies layer so as to enhance interaction between these three layers, and to be able to better evaluate residential smart energy systems in a multidisciplinary context.
Organic acid production from potato starch waste fermentation by rumen microbial communities from Dutch and Thai dairy cows
Palakawong Na Ayudthaya, Susakul ; De Weijer, Antonius H.P. Van; Gelder, Antonie H. Van; Stams, Alfons J.M. ; Vos, Willem M. De; Plugge, Caroline M. - \ 2018
Biotechnology for Biofuels 11 (2018)1. - ISSN 1754-6834
Lactate fermentation - Microbial communities - Organic acids - Renewable energy - Rumen fluid - Starch waste
Background: Exploring different microbial sources for biotechnological production of organic acids is important. Dutch and Thai cow rumen samples were used as inocula to produce organic acid from starch waste in anaerobic reactors. Organic acid production profiles were determined and microbial communities were compared using 16S ribosomal ribonucleic acid gene amplicon pyrosequencing. Results: In both reactors, lactate was the main initial product and was associated with growth of Streptococcus spp. (86% average relative abundance). Subsequently, lactate served as a substrate for secondary fermentations. In the reactor inoculated with rumen fluid from the Dutch cow, the relative abundance of Bacillus and Streptococcus increased from the start, and lactate, acetate, formate and ethanol were produced. From day 1.33 to 2, lactate and acetate were degraded, resulting in butyrate production. Butyrate production coincided with a decrease in relative abundance of Streptococcus spp. and increased relative abundances of bacteria of other groups, including Parabacteroides, Sporanaerobacter, Helicobacteraceae, Peptostreptococcaceae and Porphyromonadaceae. In the reactor with the Thai cow inoculum, Streptococcus spp. also increased from the start. When lactate was consumed, acetate, propionate and butyrate were produced (day 3-4). After day 3, bacteria belonging to five dominant groups, Bacteroides, Pseudoramibacter-Eubacterium, Dysgonomonas, Enterobacteriaceae and Porphyromonadaceae, were detected and these showed significant positive correlations with acetate, propionate and butyrate levels. Conclusions: The complexity of rumen microorganisms with high adaptation capacity makes rumen fluid a suitable source to convert organic waste into valuable products without the addition of hydrolytic enzymes. Starch waste is a source for organic acid production, especially lactate.
The impact of a household biogas programme on energy use and expenditure in East Java
Bedi, Arjun S. ; Sparrow, Robert ; Tasciotti, Luca - \ 2017
Energy Economics 68 (2017). - ISSN 0140-9883 - p. 66 - 76.
Biogas - Energy policy - Indonesia - Renewable energy
Biogas has been promoted as a renewable, cleaner and cheaper energy source. While there are several initiatives promoting the use of biogas, credible analyses of its effects on the use of alternative energy sources and energy related expenditure are limited. This study uses panel data from households engaged in dairy farming in rural East Java to assess the impact of a household level programme, which promotes the construction of digesters that produce biogas, on energy use and expenditures. Both a difference-in-difference analysis and a pipeline comparison show that the use of digesters leads to a sharp reduction in energy related expenditures and a reduction in the use of firewood and liquefied petroleum gas. However, without subsidies, the payback period of between 11 and 14 years, albeit based only on reductions in energy costs accruing from investing in a digester, is perhaps too long to justify the investment.
Variation that can be expected when using particle tracking models in connectivity studies
Hufnagl, Marc ; Payne, Mark ; Lacroix, Geneviève ; Bolle, Loes J. ; Daewel, Ute ; Dickey-Collas, Mark ; Gerkema, Theo ; Huret, Martin ; Janssen, Frank ; Kreus, Markus ; Pätsch, Johannes ; Pohlmann, Thomas ; Ruardij, Piet ; Schrum, Corinna ; Skogen, Morten D. ; Tiessen, Meinard C.H. ; Petitgas, Pierre ; Beek, Jan K.L. van; Veer, Henk W. van der; Callies, Ulrich - \ 2017
Journal of Sea Research 127 (2017). - ISSN 1385-1101 - p. 133 - 149.
Ensemble - Lagrangian approach - Marine protected areas - Model intercomparison - Ocean circulation - Renewable energy - Variability - Wind park
Hydrodynamic Ocean Circulation Models and Lagrangian particle tracking models are valuable tools e.g. in coastal ecology to identify the connectivity between offshore spawning and coastal nursery areas of commercially important fish, for risk assessment and more for defining or evaluating marine protected areas. Most studies are based on only one model and do not provide levels of uncertainty. Here this uncertainty was addressed by applying a suite of 11 North Sea models to test what variability can be expected concerning connectivity. Different notional test cases were calculated related to three important and well-studied North Sea fish species: herring (Clupea harengus), and the flatfishes sole (Solea solea) and plaice (Pleuronectes platessa). For sole and plaice we determined which fraction of particles released in the respective spawning areas would reach a coastal marine protected area. For herring we determined the fraction located in a wind park after a predefined time span. As temperature is more and more a focus especially in biological and global change studies, furthermore inter-model variability in temperatures experienced by the virtual particles was determined. The main focus was on the transport variability originating from the physical models and thus biological behavior was not included. Depending on the scenario, median experienced temperatures differed by 3. °C between years. The range between the different models in one year was comparable to this temperature range observed between modelled years. Connectivity between flatfish spawning areas and the coastal protected area was highly dependent on the release location and spawning time. No particles released in the English Channel in the sole scenario reached the protected area while up to 20% of the particles released in the plaice scenario did. Interannual trends in transport directions and connectivity rates were comparable between models but absolute values displayed high variations. Most models showed systematic biases during all years in comparison to the ensemble median, indicating that in general interannual variation was represented but absolute values varied. In conclusion: variability between models is generally high and management decisions or scientific analysis using absolute values from only one single model might be biased and results or conclusions drawn from such studies need to be treated with caution. We further concluded that more true validation data for particle modelling are required.
Practices and imaginations of energy justice in transition. A case study of the Noordoostpolder, the Netherlands
Rasch, Elisabet Dueholm ; Kohne, Michiel - \ 2017
Energy Policy 107 (2017). - ISSN 0301-4215 - p. 607 - 614.
Energy justice - Energy transition - Environmental justice - Ethnography - Renewable energy - Shale gas
Renewable energy technologies are often idealized as environmentally innocent alternatives to fossil fuels. Fossil fuel extraction is often considered as 'unjust' and renewable energy as the 'just' alternative. At the same time renewable energy projects, such as wind parks, are often resisted because of the uneven impacts of its infrastructure. This paper analyses such ambiguous meanings of energy justice (social justice issues related to energy) along the lines of its three tenets: distributional, procedural and recognition justice, aiming to understand how energy justice is constructed from below. It does so on the basis of a case study in the Noordoostpolder (the Netherlands) where plans for extracting shale gas went together with both large-scale and small-scale renewable energy practices. The paper analyses how energy justice is 'made' by how people resist shale gas and engage in 'renewable energy practices' and as such produce new imaginations and normativities of energy justice. Such an ethnographic approach helps to understand energy justice as a process of co-construction of activists, policy makers and scholars and as such responds to recent calls for a human-centred approach to the study of energy transitions. The paper is based on two and a half years of ethnographic fieldwork in the Noordoostpolder.