Marcelle C Mcmanus

• PhD, MSc, LLM, BSc
• Professor at University of Bath

Purpose Derelict fishing gear (DFG) is one of the most abundant and harmful types of marine litter that gets increasingly retrieved from the ocean. However, for this novel waste stream recycling and recovery pathways are not yet commonly established. To identify the most suitable waste management system, this study assesses the potential environmen...

With the advent of RenovaBio, Brazil has cast a new light towards the life cycle of cellulosic ethanol. Once considered a resource intensive alternative pathway to achieve the same biofuel, second-generation approaches can now provide an economic advantage due to their potentially lower carbon footprint. The exploration of lignocellulosic harvest r...

Background Heterotrophic single-cell oils (SCOs) are one potential replacement to lipid-derived biofuels sourced from first-generation crops such as palm oil. However, despite a large experimental research effort in this area, there are only a handful of techno-economic modelling publications. As such, there is little understanding of whether SCOs...

The greenhouse gas emissions associated with bioenergy are often temporally dispersed and can be a mixture of long-term forcers (such as carbon dioxide) and short-term forcers (such as methane). These factors affect the timing and magnitude of climate-change impacts associated with bioenergy in ways that cannot be clearly communicated with a single...

Background Palm oil is the most commonly used crop oil worldwide, and is used predominantly for food, in the chemical industry and for biofuels. It is mainly cultivated in areas with biodiverse and carbon-rich rainforest which has given rise to large increases in greenhouse gas (GHG) emissions and significant impacts to biodiversity. There is there...

Background Heterotrophic single cell oils (SCOs) are one potential replacement to lipid derived biofuels sourced from first generation crops such as palm oil. However, despite a large experimental research effort in this area, there are only a handful of techno-economic modelling publications. As such, there is little understanding of whether SCOs...

Decision support tools (DSTs) are increasingly being used to assist with asset acquisition and management decisions. Whether these tools are “fit for purpose” will have both economic and non-economic implications. Despite this, the on-going governance of DST performance receives only limited attention within both the academic and industry literatur...

Decision support tools (DSTs) are increasingly being used to assist with asset acquisition and management decisions. Whether these tools are “fit for purpose” will have both economic and non-economic implications. Despite this, the on-going governance of DST performance receives only limited attention within both the academic and industry literatur...

Over the past few decades there has been increasing dialogue around transdisciplinary (TD) research. However, within engineering it has received less attention and there remains a lack of consensus over both the definition, and the methods through which to conduct transdisciplinary engineering (TE). Within this paper we describe and outline the sal...

Life cycle assessment (LCA) analysts are increasingly being asked to conduct life cycle‐based systems level analysis at the earliest stages of technology development. While early assessments provide the greatest opportunity to influence design and ultimately environmental performance, it is the stage with the least available data, greatest uncertai...

Over the past few decades there has been increasing dialogue around transdisciplinary (TD) research. However, within engineering it has received less attention and there remains a lack of consensus over both the definition, and the methods through which to conduct transdisciplinary engineering (TE). Within this paper we describe and outline the sal...

This paper presents the prospects and barriers towards the utilization of biomass briquettes from forestry and agricultural residues for Lebanon, based on the actual implementation of two demonstration projects in biomass briquettes production with an output capacity of 750 tons of briquettes each. We have used quantitative techniques to aid decisi...

Marine macroalgae (seaweed) has many advantages over terrestrial crops as a source of renewable biomass but is severely underutilised at present, especially within Europe. In particular, macroalgae has elevated poly- and monosaccharide content, making it an ideal feedstock as a heterotrophic fermentation sugar source for the production of higher va...

The growth of energy crops on contaminated land offers two potential advantages over their growth on agricultural land. Firstly, it can clean the land of contaminants, remediating it for future development or agricultural use. Secondly by growing energy crops on such land there is no conflict with land that is suitable for other uses (primarily agr...

Corrosion is a significant problem in many industries, and when using stainless steel, passivation is undertaken to improve corrosion resistance. Traditionally, nitric acid is used within the passivation step; however, this has some detrimental environmental and human health impacts during its production and use. Reducing this impact is critical, a...

Biomethane is a renewable gas that can be used in existing infrastructure to reduce dependency on natural gas and lower greenhouse gas (GHG) emissions. Policy incentives have promoted a rapid implementation of biomethane production facilities using anaerobic digestion (AD). A range of feedstocks are used in AD including crops which have a higher GH...

Background Microbial oils – often termed single cell oils (SCOs) – offer an alternative to terrestrial oil crops across the energy, food and chemical industries. In addition to oils, a range of secondary metabolites can be produced from the heterotrophic organisms as part of a biorefinery system. Techno‐economic analysis (TEA) is an important tool...

Electricity generation expansion planning in Africa has focused almost exclusively on minimising costs. Yet infrastructure projects in Africa have been frequently shown to fail because planners have neglected their socio-political realm. Using the social science literature, this paper derives six political factors that are crucial for African elect...

Marine litter, in particular plastic debris, poses a serious threat to marine life, human health and the economy. In order to reduce its impact, marine litter collections such as beach clean-ups are frequently conducted. This paper presents a systematic review of temporal developments, geographical distribution, quantities and waste treatment pathw...

LCA originated in the 1960s and 1970s in the energy industry. Since then, it has evolved into a wide ranging tool used to determine impacts of products or systems over several environmental and resource issues. The use of LCA has become more prevalent in research, industry, and policy and its use continues to expand as users seek to encompass impac...

Concerns about sustainability and security of fossil energy, along with advances in biofuel technology, have simulated interest in second-generation ethanol production from lignocellulosic material. The ability to produce fuel from non-food crops and potential improved efficiencies have spurred significant scientific and socioeconomic research. Whi...

Bioenergy and biofuels are key to meeting renewable energy and carbon reduction targets. Life Cycle Assessment (LCA) techniques are being used, with varying success and consistency, to help determine the sustainability of the current fuels and pathways selected. In order to meet our longer term targets and pursue long term sustainability emerging p...

There is an increasing interest in the replacement of traditional plant based glyceride oils with microbial oils for fuel, food, dietary supplements and other pharmaceuticals and chemicals. To understand the environmental implications of this technology a systems approach is required. To date the majority of Life Cycle Assessment (LCA) studies have...

Southern Africa’s electrification is at odds with United Nations goals to provide modern energy for all by 2030. Electricity planning, a crucial tool to optimally match future supply and demand, has largely focused on minimising costs in southern Africa, sometimes complemented by a discussion of a discrete set of environmental scenarios. Political...

Universal electricity access is an important development objective, and the focus of a number of key global UN initiatives. While robust electricity planning is widely believed to be a prerequisite for effective electrification, to date, no comprehensive overview of electricity planning research has been undertaken on sub-Saharan Africa, the world...

The policy of the water sector demands integrated and resilient asset management. The majority of current research focuses on urban or community asset systems. To provide a fully integrated approach, one needs to delineate the focus of asset management at a catchment scale, to include the natural capital. The research described in this paper introd...

Ensuring that global infrastructure keeps pace with the demands of economic growth and human wellbeing is anticipated to result in spend of US$57 trillion (2013–30). Specific to the UK power sector, redesigning the electrical transmission network to support decarbonisation of the economy will result in an estimated spend in the region of US$50 bill...

Combating Performance Decay of Decision Support Tools

Bioenergy is increasingly being used to meet EU objectives for renewable energy generation and reducing greenhouse gas (GHG) emissions. Problems with using biomass however include high moisture contents, lower calorific value and poor grindability when compared to fossil fuels. Torrefaction is a pre-treatment process that aims to address these issu...

The cost, availability, and sustainability of feedstocks are key to successfully producing aviation biofuels. There are numerous routes to aviation fuels, and as such, it is likely that multiple feedstocks will be used globally to produce future aviation biofuels. In this chapter, a general overview of all the major feedstocks available, where they...

Biomass sustainability criteria were introduced in the UK following the EU Renewable Energy Directive. Criteria are now applicable to solid biomass and biogas, however because it is not mandatory criteria can be adapted by member states with the risk of different interpretation. Operators are required to report greenhouse gas (GHG) emissions for ev...

With fossil fuels still predicted to contribute close to 80 % of the primary energy consumption by 2040, methods to limit further CO2 emissions in the atmosphere are urgently needed to avoid the catastrophic scenarios associated with global warming. In parallel with improvements in energy efficiency and CO2 storage, the conversion of CO2 has emerge...

This study quantifies the increase in the peak power demand, net of non-dispatchable generation, that may be required by widespread adoption of heat pumps. Electrification of heating could reduce emissions but also cause a challenging increase in peak power demand. This paper expands on previous studies by quantifying the increase in greater detail...

Bioenergy is increasingly used to help meet green-house gas (GHG) and renewable energy targets. However, bioenergy’s sustainability has been questioned, resulting in increasing use of life cycle assessment (LCA). Bioenergy systems are global and complex, and market forces can result in significant changes, relevant to LCA and policy. The goal of th...

LCA has evolved from its origins in energy analysis in the 1960s and 70s into a wide ranging tool used to determine impacts of products or systems over several environmental and resource issues. The approach has become more prevalent in research, industry and policy. Its use continues to expand as it seeks to encompass impacts as diverse as resourc...

This paper takes an integrated analysis approach to explore the options available for a UK homeowner to reduce their domestic emissions to the level advised by the UK governments Committee on Climate Change of 20% of those associated with a typical house in 1990. It uses proven thermal models of a typical house and low carbon heating systems to est...

The UK has targets to reduce carbon emissions by 80% by 2050 compared to a 1990 baseline. The Transition Pathways research consortium has generated a set of three low carbon UK electrical futures, together with the corresponding technology mixes. All require a significant amount of technological change, including a significant increase in the contr...

Torrefaction is a thermal pre-treatment process for upgrading raw biomass into a more energy dense fuel. Torrefied biomass is combined with a densification process to increase its bulk density similar to conventional wood-pelleting production. This paper identifies the significant environmental impacts associated with production and delivery of the...

Occupants of dwellings with grid-connected photovoltaic (PV) systems can often benefit financially from exporting electricity to the grid. When export prices are lower than import prices, however, occupants are incentivised to time-shift demand in order to avoid exports and reduce imports. To maximise this potential financial benefit, the addition...

The potential impacts of participating in demand side management (DSM) on the performance of air source heat pumps (ASHP) and micro-combined heat and power (mCHP) units are considered by this study. As significant consumers and generators of electricity at the distribution level, large numbers of heat pumps and micro-cogenerators would provide cons...

Production of Portland cement (PC) binders contributes substantially to global CO2 production and various bodies including the Intergovernmental Panel on Climate Change (IPCC) have identified geopolymers as alternative binders with the potential to reduce these emissions. The hypothesis of this research is to investigate whether this is a realistic...

The Renewable Energy Directive (RED) specifies that biomass feedstocks must be sustainable and are not directly implicated with conversion of areas of high carbon stock and biodiversity. There are concerns that first generation biofuels from food-based crops will lead to negative indirect impacts on food prices and place pressure on agricultural la...

Biomass gasification is regarded as a sustainable energy technology used for waste management and producing renewable fuel. Using the techniques of life cycle assessment (LCA) and net energy analysis this study quantifies the energy, resource, and emission flows. The purpose of the research is to assess the net energy produced and potential environ...

The relative performances of six air source heat pumps (ASHP) and a solid oxide fuel cell micro-combined heat and power (SOFC-mCHP) unit are compared using a modelling approach. The emphasis is in indicating the effect of a wide range of operating conditions and methodologies, rather than detailed analysis of the performance of the units under limi...

Purpose The aim of this paper is to highlight the challenges that face the use of life cycle assessment (LCA) for the development of emerging technologies. LCA has great potential for driving the development of products and processes with improved environmental credentials when used at the early research stage, not only to compare novel processing...

In latitudes between 50 degrees and 60 degrees north domestic hot water is frequently provided by the house's central heating boiler. These are run for short periods in the summer just to provide hot water, this tends to be inefficient. In places with a constant solar climate it should be possible to rely on solar energy to provide domestic hot wat...

Within the United Kingdom a significant portion of the energy consumed each year is done so through industry. It is therefore desirable to take measures that reduce this consumption. A process common to all manufacturing sectors is that of packaging, and this research focused on identifying, quantifying and reducing the environmental impact of one...

In light of concerns over climate change and the need for national inventories for greenhouse gas reporting, there has been a recent increase in interest in the ‘carbon foot printing’ of products. A number of LCA-based carbon reporting tools have been developed in both the agricultural and renewable energy sectors, both of which follow calculation...

This study uses the life cycle assessment (LCA) environmental management tool to measure the performance, at laboratory scale, of a range of iron and palladium based nanoparticle catalysts for carbon dioxide utilisation (CDU). The catalysts combine the reverse-water gas shift reaction with the Fischer–Tropsch process to convert carbon dioxide (CO2)...

This work considers the potential reduction in the carbon dioxide emissions associated with the operation of Air Source Heat Pump which could be achieved by using demand side management. In order to achieve significant reductions in carbon dioxide emissions, it is widely envisioned that electrification of the heating sector will need to be combined...

There is a common assumption that to decarbonise the heat market in the UK a large number of households will need to switch from fossil fuel heating to heating with low carbon electricity. Electric heat pumps are the most energy efficient way of using electricity for space heating so it would appear logical to promote their use. Domestic electricit...

A life cycle assessment (LCA) has been conducted on the growth of multi-walled carbon nanotubes (MWNTs) via catalytic chemical vapour deposition (cCVD). Using a directly measured process, a cradle-to-gate approach has been employed for this assessment whereby analysis of the synthetic routes of the reactants used, the process energy inputs, the equ...

This paper outlines the results of a comprehensive life cycle study of the production of energy, in the form of biogas, using a small scale farm based cattle waste fed anaerobic digestion (AD) plant. The life cycle assessment (LCA) shows that in terms of environmental and energy impact the plant manufacture contributes very little to the whole life...

Energy and exergy analysis is employed to compare the relative thermodynamic performance of low-carbon domestic energy systems based on air source heat pumps and micro-combined heat and power (cogeneration) units. A wide range of current units are modelled under different operating conditions representative of the United Kingdom to determine the en...

Biodiesel is often considered to improve energy security and reduce the impact of fuel on climate change. However there are concerns about the impact of biodiesel when its life cycle is considered. The potential impact of using biodiesel rather than conventional diesel was investigated using a life cycle assessment (LCA) of rapeseed biodiesel. Biod...

Biomass is considered to be a low carbon source of fuel, where the carbon sequestered by during crop growth is released during combustion. The energy available from biomass is considered virtually 'carbon neutral', with the exception of some emissions incurred through the cultivation, transport and production of the fuel. Biomass is therefore consi...

Ethanol produced from lignocelluloses is expected to make a major contribution on transportation fuel markets. In this paper, a life cycle assessment was carried out to assess the environmental burdens of ethanol production from wheat straw and its use as ethanol blend fuels. Two ethanol based fuel E15 (a mixture of 15% ethanol and 85% petrol by vo...

Bioenergy from lignocellulosic biomass offers the potential to provide a significant source of clean, low carbon and secure energy. In recent years, a number of studies have been carried out to assess the environmental performance of lignocellulosic ethanol fuel. However, the complexity of biofuel systems generates significantly different results d...

Under the Kyoto Protocol many countries have targets to reduce carbon emissions and increase renewable energy production. In order to do this effectively the impact and efficacy of differing schemes must be determined. One option for producing electricity is through the use of a tidal barrage. The largest potential barrage scheme considered in the...

Adoption of small scale micro-generation is sometimes coupled with the use of batteries in order to overcome daily variability in the supply and demand of energy. For example, photovoltaic cells and small wind turbines can be coupled with energy storage systems such as batteries. When used effectively with renewable energy production, batteries can...

The UK transport sector is currently responsible for 30% of UK CO 2 emissions. Therefore, the use of biofuels is explored. As the CO 2 released when energy is generated from biomass is generally balanced by that absorbed during the fuel's production it is often regarded as a 'carbon neutral' process. However, there are impacts associated with bioen...

Biofuels have been identified as a potential short-term solution for reducing greenhouse gas (GHG) emissions from road transport. Currently, '1st generation' biofuels are produced from food crops, but there are concerns with the indirect effects of utilising edible crops for fuel. There is increased interest in producing '2nd generation' biofuels f...

Energy and exergy analysis is employed to compare the relative thermodynamic performance of Air Source Heat Pumps (ASHP) with that of micro Combined Heat and Power (mCHP) units. The effect of varying the heat to power demand ratio is considered in order to provide insights regarding their relative merits both now and for a 2020 scenario. Exergy ana...

Barriers to UK bioenergy development arise from a number of technical, financial, social and other constraints. Likewise, the drivers for using bioenergy are numerous and diverse. A range of these barriers and drivers have been identified through a comprehensive literature and case study review, and then assessed through an online questionnaire, co...

The potential global demand for biofuels and the implications of this for land use and its interaction with food agriculture is reviewed. It is expected that biofuels will form an important element of global transport energy mix (in the order of 20–30% of total requirement) over the next 40 years and beyond. Over this time, there will be a transiti...

With increasing renewable energy targets and the use of biomass for energy production, questions arise about the sustainability of differing types of bioenergy. Much has been made about the renewable transport fuel obligations and the impact the production of biofuel can have on the environment, but there has been less consideration of more small s...

The life-cycle impacts of five different 11 kV electrical power cables (three overhead lines and two underground cables) were analysed. These were compared by their embodied impacts in production and total lifetime operational impacts. The life-cycle results revealed there to be three key issues, the impacts of climate change, fossil fuel depletion...

An ‘integrated appraisal’ of a solar hot water (SHW) system in the UK residential sector was carried out to assess its overall energetic, environmental and economic performance. The energy analysis indicates that when displacing a gas boiler, oil boiler, or electrical immersion heater, the SHW system would provide a net energy benefit for the major...

The life cycle energy use and environmental impact of an installed micro-wind turbine for domestic (residential) electricity generation has been determined. The turbine examined was a horizontal-axis wind turbine, which has a rotor diameter of 1.7 m, a power rating of 600 W at 12 m/s, and an assumed lifetime of 15 years. The system boundaries for t...

Approximately 38% of current UK greenhouse gas emissions can be attributed to the energy supply sector. Losses in the current electricity supply system amount to around 65% of the primary energy input, mainly due to heat wasted during centralised production. Micro-generation and other decentralised technologies have the potential to dramatically re...

Bioenergy will need to play a significant role in the future of Europe's energy provision in order to maintain energy security and sustainability. In this context, a regional assessment of biomass availability for energy use has been carried out for the south west region of England. Current bioenergy production, the maximum present resource availab...

A range of integrated appraisal techniques have been utilised to study the comparative performance of various domestic micro-generators that have been proposed as possible decentralised energy resources for 'low carbon' buildings. Energy, environmental impact and cost-benefit analysis methods, employed on a 'whole systems' basis, are described. The...

The UK transport sector has the fastest rate of growth in terms of primary (and end-use) energy consumption, and is currently responsible for 30% of UK CO2 emissions. Biofuels could significantly reduce the emissions from the road-transport sector if they were widely adopted. They have been shown to reduce carbon emissions, and may help to increase...

A common characteristic of water demand in urban areas worldwide is its inexorable rise over many years; continued growth is projected over coming decades. The chief influencing factors are population growth and migration, together with changes in lifestyle, demographic structure and the possible effects of climate change (the detailed implications...

The use of rapeseed oil in mobile hydraulic systems has become more widespread over recent years. This is because of concern about the environment in which the systems work and the perceived benefit of using such fluids. This article examines the major segments of the life cycle of mineral and rapeseed oil as used in mobile hydraulic systems, with...

Life-cycle assessment (LCA) techniques have been used in order to evaluate the environmental impact of conventional oil ‘hydraulic’ systems in an ecologically-sensitive application; that of mobile forestry machinery typical of modem European design. A single-grip ‘harvester’ employed for logging and a ‘forwarder’ that subsequently transports the fe...

Life-cycle assessment (LCA) techniques have been used in order to evaluate the environmental impact of conventional oil 'hydraulic' systems in an ecologically-sensitive application; that of mobile forestry machinery typical of modern European design. A single-grip 'harvester' employed for logging and a 'forwarder' that subsequently transports the f...