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This document is a report for STFC for the project titled 'Ammonia on-farm Life cycle assessment of different ammonia uses on a farm'.

Using life cycle assessment, this study compared three uses of ammonia produced via a Haber-Bosch facility on a remote farm in Scotland. The three ammonia uses compared in this study are:

Aqueous ammonia fertiliser

Ammonia vehicle fuel

Ammonia CHP

These uses were compared with traditional alternatives:

Urea fertiliser

Diesel tractor

Natural gas CHP

The study found that aqueous ammonia fertiliser provided the largest environmental benefit out of the three ammonia uses. While ammonia vehicle fuel and ammonia CHP were found to provide environmental benefits across most indicators, in some areas the traditional alternative was preferred. This was not the case for ammonia fertiliser.

This report is divided into the following sections:

1. Introduction
2. Goal
3. LCA Specification
4. The LCA Model
5. Analysis of Results
6. Conclusion
7. Appendices

To assess and improve the production from European biogas plants a specific targeted research or innovation project (Project no. 513949) entitled 'European Biogas Initiative to improve the yield of agricultural biogas plants' involved collating data from 13 biogas plants across Europe. Data was collected by four means; the use of periodic data from the biogas plant, weak-point analysis from each of the biogas plant operators; a questionnaire and a schematic of each plant. The information revealed that although the biogas plants were performing relatively well, with an average specific biogas yield 0.44 m3.methane.kg-1 VS and an average methane productivity of 1.25 m3.m3, there was considerable capacity to improve the performance of each of the biogas plants by a range of different means.

Economic comparison of these biogas plants across Europe was difficult. However, about 90% of the revenue was realised from electricity sold. The average specific capital expenditure for the 13 biogas plants was about 4,400 € per installed electric capacity (kW) or at 5% discount rate and 15 years economic life, 5.3 €-Cent per kWh of electricity. The average costs of feedstock was 5.6 €-Cent per kWh electricity produced. Also the average cost was 67 €-Cent per Nm³ of methane produced. The average total costs were 19.5 €-Cent per kWh electricity produced which was slightly above the price paid in most of the countries involved.

Development of improved means of both introducing and treating the feedstock was important for improved biogas yields. The hydrolysis of crops and crop residues could significantly reduce the HRT of some digesters to below 100 days. The type and mixture of feedstock also influenced the biogas yield and optimisation of the inputs would be of benefit. However each feedstock may ferment at different rate and/or require different conditions so process control could produce more biogas. High levels of manure required up to 4 times as much volume as other feedstocks to produce the same amount of biogas. There was up to 3 times the methane output per kg VS from different biogas plants. Some biogas plants had a variability (on standard deviation) of the specific methane yield as low as 7% others could be considered unstable with values over 100% of their mean values. Feedstocks were considered responsible for this variability, however such a range suggests that process monitoring and control would provide more stable biogas production and improved biogas yields. Monitoring fermentation parameters was limited to pH and volume of the various vessels for all biogas plants. Sensors did include means of measuring VFAs (36% of the total) and conductivity (18%) and redox potential (9%) for the 13 biogas plants. The outcome of this study will be used to identify demonstration projects at different biogas plants and research facilities.

The objective of this project is to develop a stable thermophilic micro-organism able to produce high yields of ethanol from a variety of hydrolysed lignocellulosic feedstocks which are cheap and readily available.

The cost of production of bioethanol for fuel is prohibitively high compared with gasoline, due to the expensive sugar or starch feedstock required, the low production rates and the inability of conventional yeast fermentation to utilise the pentose sugars found in plant biomass. Some yeasts have been engineered to utilise pentose sugars but these modified yeasts produce a significantly decreased, economically unviable, ethanol yield.

Thermophilic bacteria have tremendous potential in the production of ethanol. Their high temperature fermentations offer reduced cooling costs, direct recovery of ethanol from the hot culture and high productivities, because of high growth rates and yields. This project aims to manipulate such thermophilic organisms to eliminate the organic acid production and maximise ethanol formation.

This profile contains information on the project's:

Objectives

Summary

Contractor

Collaborator

Cost

Duration

The research carried out was designed to test the efficacy of enzyme induced tallodiesel production as a potential for the next generation of transport fuel use. The aim was primarily to test the technical innovation, then to assess the economic potential and explore opportunities for application to market within the next 25 years.

Biodiesel is an alternative to petroleum-based diesel fuel made from renewable resources such as vegetable oils or animal fats. Chemically, it comprises a mix of mono-alkyl esters of long chain fatty acids. A lipid transesterification production process is normally used to convert the base oil to the desired esters and remove free fatty acids. The biggest source of feedstock for biodiesel production is oil from crops or other similar cultivatable material. Plants utilize photosynthesis to convert solar energy into chemical energy. It is this chemical energy that biodiesel stores and is released when it is burned. Therefore plants can offer a sustainable oil source for biodiesel production.

This project aimed to provide technological proof for the biochemical conversion of low-grade tallow into tallodiesel by enzyme mediated alcoholytic transesterification of fats and free fatty acids to alkyl esters. It also intended to support the potential roll out of this technology via a techno-economic study (and initial LCA) to determine an economically beneficial conversion.

The project research indicated that enzyme mediated alcoholysis of tallow is a potentially viable route for the production of biodiesel, however efficient scale up has not been achieved. There is a good indication that the method would provide an ideal route for the disposal of animal by-product and that the added value would result in a no-cost option that has every potential for resulting in profit, provided that correct economies of scale apply.

This report is divided into the following sections:

1. Review of Biodiesel
2. Influence of feedstock chemicals
3. Protocol for synthesis
4. Residues
5. Techno-economic evaluation
6. Lifecycle Analysis
7. Conclusions
8. References

ETI’s Strategy Manager Hannah Evans presents “Making efficient use of bioenergy feedstocks for cleaner, greener energy” at an Energy Institute lecture on 27 November 2017 (slide set)

This document is a report for the project titled 'Outline Feasibility of Centralised Anaerobic Digestion Plants linked to Dairy Supply Chain'.

Dairy UK and AEA Energy & Environment have undertaken a high level assessment of the feasibility of centralised anaerobic digestion (CAD) in the dairy processing sector. This was based on the identification of 10 potential sites that could host centralised anaerobic digestion plants. The work comprised technical, economic and environmental assessments.

This work has confirmed our previous findings that centralised anaerobic digestion plants, based at or close to industrial dairy sites, have the potential to be economically attractive, as several positive factors would combine in their favour, with payback periods as low as 3 years. This is because they can be designed to co-treat organic wastes from industrial dairy sites along with animal wastes from nearby livestock farms and other food manufacturing wastes. As the cost of landfilling will continue to rise due to the Landfill tax, producers of industrial food waste will increasingly need outlets such as AD plants. Inclusion of these will help to increase the viability of the CAD by providing a diverse feedstock and by providing an additional income stream to the plant operator.

The successful exploitation of CAD depends on gaining the full economic benefit of the outputs combined with full exploitation of ancillary benefits. Generation and utilisation of biogas is one of the key benefits of adopting anaerobic digestion process for treating biodegradable wastes. The Government already provides incentives that contribute to improving the economics of biogas utilisation, through the Renewable Obligation, Climate Change Levy (CCL) exemption and Enhanced Capital Allowance. There is potential for additional energy income from the sale of heat generated from the combined heat and power (CHP) scheme, but this would depend on the development of infrastructure to deliver the heat to where it is needed within a few hundred meters. Assessment of land use around the 10 identified potential CAD sites showed that there would be sufficient area to return digestate to land within a 7.5 km radius.

The CAD schemes can provide the industrial dairies with several environmental benefits that will also help them to consolidate or secure new market outlets. For instance, a significant proportion of their carbon footprint could be reduced -which will help those dairies to link up favourably with C-labelling schemes which are being planned by retail chains and the Carbon Trust.

This report contains and executive summary, and is divided into the following sections:

1. Introduction
2. Assessment of CAD plants
3. Potential CAD schemes
4. CAD scheme development
5. Conclusions and recommendations

• Appendix 1 - Questionnaire - Confidential
• Appendix 2 - Techno-economic assumptions

In the context of UK energy system decarbonisation, the value of bioenergy within the energy system is greatest when combined with CCS (Carbon Capture and Storage) to deliver negative emissions. Strategies to develop a CCS sector in the UK must include Bioenergy with CCS (BECCS). In the absence of CCS, the value of bioenergy is greatest when producing gaseous or liquid fuels for use in sectors which are otherwise difficult to decarbonise, and where no lower-carbon options are readily available. The flexibility of gasification with syngas clean-up makes it resilient to wider energy system decisions. Investment is needed to deploy this technology at a commercial scale. The UK has the potential to increase biomass feedstock production in ways which deliver additional environmental benefits. Greater focus is needed on developing markets and business models which encourage new planting in suitable locations. To develop and expand the UK bioenergy sector sustainably and in a way which is strategically valuable to the UK�s decarbonisation efforts, action must be taken to develop sustainable feedstocks supplies and demonstrate the technical and commercial viability of key technologies. This report sets out four key recommendations to help the UK capitalise on key opportunities to develop the bioenergy sector: Create the right environment for BECCS in the UK, which through deployment can significantly reduce the cost of meeting the UK�s 2050 emissions targets and increase the likelihood that the UK can deliver net-zero emissions. Develop gasification for the production of clean syngas from biomass and wastes to enable the bioenergy sector to remain robust to changes elsewhere in the energy system. Increase biomass production and the supply of sustainable biomass for bioenergy in the UK, and maximise the use of appropriate residual waste resources for energy, to enable the delivery of greater emissions savings at a system level. Deliver more physically and chemically consistent feedstocks to end users, through improvements in plant breeding and pre-processing, and/or develop conversion technologies more resilient to variations in feedstock composition.

Reducing CO₂ emissions from UK transport is likely to require a combination of measures, including increased energy efficiency, new technology introduction, and fuel switching. Apart from demand-side management, the most important technologies can be divided into (a) vehicles and (b) fuels.

Key vehicle technologies are:

Battery electric vehicles, for niche markets including urban journeys

Hybrid-electric vehicles, replacing conventional gasoline and diesel vehicles

Fuel cell vehicles, potentially able to replace all conventional vehicles

Different fuels can be used in these different vehicles:

Electricity will be required for battery vehicles, and for some hybrids, known as plug-in hybrids

Biofuels can be introduced either as blends in current fuels, and used in current vehicles and hybrids, or potentially at levels of 100% with some engine modifications

Hydrogen is probably required for fuel cell vehicles, and could be also used in internal combustion engines

Each of these technologies and fuels faces technical, cost and policy challenges before it can compete commercially. However, these do not appear insurmountable. Each also offers benefits other than simply possible reductions in CO₂ emissions from transport. In the near term, hybrid vehicles and biofuels are expected to be the main contributors to reductions in emissions. The environmental impact of biofuels is complex and care should be taken in evaluating and monitoring their real-world effects, especially if either raw materials or finished fuels are imported. In the longer term, but only if technical development is successful, fuel cell vehicles using hydrogen offer the potential for major emissions reductions.

The table below gives indicative figures, and ranges, of costs of carbon reduction from different fuels and routes. It is extremely important to note the uncertainty inherent in all of the cost and price assumptions made here, especially as the timescales increase. Robust policy must be based not only on these numbers, but also on other factors that have not been examined under the analysis conducted for this report.

This report contains an executive summary, and is divided into the following sections:

1. Introduction
2. Important Issues and Caveats
3. Vehicle Technologies
4. Fuels
5. Technology and Cost Issues and Other Barriers
6. Costs of Energy Use and CO₂ Emission Reduction
7. Policy
8. Summary