Blog posts

Methane emissions from biogas facilities are underestimated

A blog by Dr Semra Bakkaloglu, a Research Associate at the Sustaianable Gas Institute. 

Biogas production could have an important role in renewable energy, reducing the adverse effects on the climate. However, biogas production’s contribution to emissions of the greenhouse gas, methane, is not fully understood. Methane (CH4) is the second most potent and abundant greenhouse gas after carbon dioxide (CO2) but because it only lasts in the atmosphere for short time (a decade) reducing methane emissions could have a more rapid impact on mitigating climate change. Unfortunately, there are significant discrepancies between official inventories of methane emissions and estimates derived from direct atmospheric measurement of biogas plants.  If biogas is to be a solution to climate change, we need to find effective emission methane reduction strategies, and sources also need to be properly quantified.

What is biogas?

According to the United Nations Framework Convention on Climate Change (UNFCCC), biogas is defined as gas generated from anaerobic digesters. Biogas plant feed may be any biodegradable material, such as dedicated energy crops, agricultural residues, organic waste and paper mill waste. The integrated process in biogas plants includes feedstock supply and pre-treatment, gas treatment and utilisation, and recovery, pre-treatment and use of digestate (Wellinger et al., 2013). This comprises 50 to 70% methane, 30 to 50% CO2 and traces (1 to 5%) of hydrogen suphide and ammonia (National Non-Food Crops Centre, 2021). Biogas is used for heating, electricity or both. If biogas is upgraded to biomethane by removing other gases, biomethane has similar properties to natural gas and can be injected into gas grid or used as a road fuel.

Emissions from biogas plants

Biogas production has an important place in renewable energy, reducing the adverse effects on the climate. However, high methane emissions from biogas plants can arise from fugitive emissions. Depending on engine construction, plant design and operation conditions, emissions can occur through venting from compressors, pipes, single large leaks or long-lasting pressure relief valves and incomplete combustions from combined heat and power units.

Biogas plant and field
Figure 1: One of the UK’s biogas plants

Biogas plants not accounted for

Waste practices in the EU and the UK have changed recently as more waste is being diverted from landfill to biogas plants and composting facilities. There are 579 biogas plants in the UK (National Non-Food Crops Centre, 2021) and their number of biogas plants has grown in the last decade (Figure 2). Unfortunately, most have not been included in the National Atmospheric Emission Inventory (NAEI).

The sustainability of biogas plants depends on the land requirement and greenhouse gas accounting (OFGEM, 2018). However, studies have shown that there is often a maximum loss of 9% of the total production rate of methane (Bakkaloglu et al., 2021; Scheutz and Fredenslud, 2019, and Samuelsson et al. 2018). Also, research conducted by my colleagues and I at Royal Holloway in 2021, demonstrated that biogas plants emissions may account for up to 3.8% of the total methane emissions in the UK. This does not include the sewage sludge biogas plants. We therefore need robust, consistent emission measurements in the UK. Legal requirements should also be implemented, not only UK Net Zero Commitment, but also for the sustainability of biogas plants.

Biogas in the UK’s Net-Zero Commitment

Figure 2. Biogas plant market in the UK (Source: Anaerobic Digestion and Bioresources Association, 2019)

On 27 June 2019, the UK government committed to achieving net-zero Carbon emissions by 2050, in line with the UN’s Paris Agreement (Climate Change Committee, 2019). This Agreement sets out many recommendations as to how to achieve net-zero targeted, including:

  • Diversion of all biodegradable waste from landfills to anaerobic digesters or composting facilities by 2025.
  • Measures to reduce emissions from livestock, soils and waste manure.
  • Elimination of food waste as far as possible, and separation of food waste collections
  • Full utilisation of the UK’s biogenic waste sources, including residues from agriculture and forestry.

According to a recent article on the UN website in December 2020, more than 110 countries have a carbon neutral strategy by 2050 but this aim can only be achieved with appropriate reduction methods. As a result of this zero-commitment, biogas plants have assumed a more significant role, not only in the renewable energy market but also in waste strategies.

Although emissions from biogas plants have not, as yet, attracted serious attention, they may jeopardise the net-zero commitment unless the necessary action is taken.


What are the best options for road freight transport?

Pedro Gerber Machado, a visiting researcher from the University of São Paulo, Brazil, summarises his recent review paper examining the life cycle emissions for road freight transport. The review was carried out in collaboration with the Institute of Energy and Environment at the University of São Paulo, Brazil.

Author: Pedro Gerber Machado

The transport sector is responsible for around 30% of the world’s energy consumption and 16% of greenhouse gases (GHG) emissions.  To achieve an energy transition to guarantee net-zero emissions, reducing emissions from road transport is fundamental. Diesel is still the most common fuel used for heavy road transport and freight. While worldwide there is a move towards electric vehicles, their environmental benefit in reducing emissions depends on the area’s electricity sources. Our review paper examines the total environmental life cycle emissions of different fuel options and technologies for road freight transport (trucks) in 45 studies.

Electric vehicle
Source: Pixabay

Source of electricity

The source of electricity can make a big difference to greenhouse gas emissions. We found that with greenhouse gas emissions, higher values (3,148–3,664 g/km) are found in places where coal has a significant share in electricity generation. Lower emissions are found where renewables have higher percentages in electricity generation (496 g/km). In China, emissions can reach 5,479 g/km since electricity generation “is mostly from coal.”

Compressed Natural Gas (CNG)

For Compressed Natural Gas (CNG) technology, greenhouse gas emissions vary due to differing efficiency and assumptions about methane leakage during natural gas transportation. But future projections are optimistic due to the potential for improvements in controlling methane emissions (514 g/km in 2050).


In the analysis, biodiesel had a higher energy consumption and higher emissions profile in the production phase equal to diesel, which is the main reason for its low environmental performance.


The greenhouse gas emissions intensity from hydrogen varies as it is depends on its method of production such as coal gasification, steam methane reforming (SMR), and hydrolysis. The use of carbon capture and storage (CCS) and liquid or gaseous use also influences its final emission profile.

Fuels vs. diesel

On average, the review showed that biogas, fuel-cell hydrogen, and Liquefied Natural Gas (LNG) have lower emissions in their life cycle than diesel, with a chance of a 57% reduction in emissions for biodiesel, 77% for fuel-cell hydrogen, and 100% chance for biogas. Interestingly, even though biodiesel is a renewable source of fuel that receives significant attention due to its capacity to reduce greenhouse gas emissions, in our review, it had a higher average emission than diesel.

Electric car
Source: Pixabay

Battery electric, hydrogen fuel cells and biogas

We found that if a clean electricity matrix is available, with high renewable energy shares, battery electric vehicles provide the best option. Hydrogen fuel-cells, when hydrogen comes from renewable sources, are also comparable to battery electric vehicles. Biogas can serve as a feedstock for hydrogen production in substituting natural gas in steam methane reform or liquefied for use in Liquid Natural Gas (LNG) trucks.

Further research into biogas emissions, fuel consumption, and its economics is essential. Since biogas production is possible from several sources, it could be suitable for different countries, such as Brazil.

Analysing air pollutants

There is a lack of studies exploring the life cycle of these options when it comes to air pollutants. Even though pollutant emissions in the use phase (for internal combustion options) have received more attention from the scientific community, emissions for the whole life cycle should also be studied. Even so, uncertainties related to the Tank-to-Wheel evaluation can increase the inaccurate values from this side of the analysis and the error propagation, directly impacting the policymakers. For PM2.5, hybrid and LNG options have greater changes in reducing the emissions. Fuel-cell, LNG, CNG, and hybrid trucks have higher chances of reducing nitrogen oxide (NOx) emissions. In contrast, sulphur oxide (SOx) emissions came out inconclusive due to a lack of studies.

But what about the economics…

CNG, LNG, and hybrid trucks were the best options from an economic perspective. CNG has lower life cycle costs and fuel costs in most analyses, with values ranging from 50% lower life cycle costs than diesel to a 2% reduction, to 16% average increase. CNG is the most economical fuel for large fleets that conduct urban operations and can support private infrastructure.

LNG could have a payback time of 2.5 years or lower, considering the price differential mostly in long-haul operations due to its lower fuel costs. However, economic viability could be achieved due to the higher cost of LNG vehicles and maintenance and the limited range of LNG trucks relative to diesel. The studies also showed that the fuel efficiency in LNG trucks could dictate its economic viability. Relative efficiencies of less than 80% reduce the chances of lower costs by 50%.

Finally, hybrid trucks show a total life cycle cost from 10% lower to practically no difference. Although the incremental cost of hybrid trucks is expected to become close to zero in the future, additional investments of more than $35,000 in hybrid technology hinder its viability, especially with low diesel fuel costs.

In the developing world…

The question arises then if the best options regarding GHG and local pollutant emissions will ever be a possibility for developing regions. Even though authors point out that electric trucks could cause an increase in emissions in several places in the world and that it is still necessary to evaluate peak power demand to understand the operational aspects of transport electrification, electric trucks in countries with a high share of renewables have the most radical reductions in GHG. However, being the most expensive options, there is a slight chance that governments in poorer countries or even the private sector will be willing to pay the price, based solely on environmental reasons.

The way to go in these countries has been to continue to depend on diesel. Most recently, the discussion on natural gas use in the transport sector has gained some momentum. Cheaper than other alternative options, natural gas might be an option due to its lower PM emissions, even though other pollutants, or GHG emissions, are higher.


How much methane does the oil and gas sector emit?

By Dr Jasmin Cooper

Research Associate, Sustainable Gas Institute 

Methane is a major greenhouse gas and in recent year many companies in the oil and gas value chain have either joined initiatives or set ambitious targets in a bid to curb their emissions e.g. the oil and gas methane partnership (OGMP), the oil and gas climate initiative (OGCI) and methane intensity targets set by major oil and gas companies (GMI, 2020, OGCI, 2018, Shell, 2018, Xu et al., 2020). The quantification of emissions is undoubtably a key component of emission reduction strategies, but there is a high level of uncertainty in the emissions data globally. This is largely because, in comparison to carbon dioxide, there was a lack of interest until the second half of the 2010s when post the Paris Agreement, a spotlight was shone on short-lived climate forcers (e.g. methane, ozone, black carbon) and their role in reducing warming.

The global atmospheric concentration of methane has been increasing since preindustrial times and since the 1980s it has been rising rapidly (Dlugokencky, 2021). The International Energy Agency (IEA) reported in their Methane Tracker that oil and gas methane has been rising since the year 2000, with emissions peaking in 2019 (IEA, 2021b). The impacts of COVID-19 appear to have led to a drop in emissions, because of reductions in oil and gas demand because of slowdowns in industrial and economic activity. However, post COVID-19, it is imperative that 2019 remain the emissions peak if the sector is to contribute towards net-zero ambitions. This is because with methane being a potent greenhouse gas, reductions in emissions can lead to significant climate change and global warming benefits.

In the oil and gas sector, as well as in other sectors, methane emissions are quantified using one (or a combination) of three methods (National Academies of Sciences and Medicine, 2018): engineering calculations (including process modelling/simulation and using equipment specifications), emission factors (coefficient used to calculate emissions) and direct measurement. Out of these three, direct measurement is the most accurate for quantifying emissions and is also the only method which allows for the accounting and identification of emission sources. Data derived from direct measurement are also value inputs in emissions modelling via process simulation, as well as in updating or deriving emission factors. There is a broad spectrum of quantification technologies available, ranging from handheld devices, such as flow meters, to remote devices, such as observation stations and satellites. The measurement capabilities of these technologies also vary along the spectrum, from low level to extremely high emission rates and quick measurements to hours long measurement surveys.

However, quantifying emissions through direct measurement is expensive and time consuming. This, in combination with the lag in methane interest has results in a large proportion of global oil and gas related methane emissions being quantified using generic emission factor data. Major oil and gas countries such as the USA, Norway and Australia quantify their emissions using data derived from measurement campaigns, while others such as Egypt, Malaysia and Bolivia rely on default emission factors. Also, the sections of the oil and gas value chain (upstream, midstream and downstream) vary in how emissions are quantified. In countries which are major gas importers, such as Japan, Italy and Germany, emissions from the midstream and downstream activities are quantified using data derived from measurement surveys, while emissions from any upstream production and processing activities are quantified using either generic emission factors or country specific emission factors derived from expert estimates and industry reports.

Therefore, it is clear that actions need to be taken to homogenise the quality of both the emissions data and the emissions reporting, both between countries and within countries. The IEA launched in January 2021 their regulatory roadmap and toolkit (IEA, 2021a), which aims to provide guidance for policy makers who are looking to develop regulations to tackles their oil and gas methane emissions. A key step in this roadmap is developing an emissions profile.

For this step, accurate emissions data is needed, not just in magnitude of emissions and identifying all emission sources, but also in determining emission patters e.g., constant continuous, intermittent, episodic, inter-daily variable and intra-daily variable. These are important as they will directly impact any abatement measures and strategies developed, as well as any new regulations introduced to curb emissions. Hence, more efforts must be put into measuring emissions in all active oil and gas countries (both producers and consumers). The effectiveness of methane abatement measures will be hindered if the underlying emissions data is poor as either not enough or too many efforts could be put in, or efforts are not targeting the key emission sources.


Dlugokencky, E. 2021. Trends in atmospheric methane: Global CH4 monthly means [Online]. Boulder, CO, USA: National Oceanic and Atmospheric Administration/Global monitoring Laboratory (NOAA/GML). Available: [Accessed].

GMI. 2020. UNEP: Oil and Gas Methane Partnership Initiative to Manage Methane Emissions from Upstream Oil and Gas Operations [Online]. Global Methane Initiative (GMI). Available: [Accessed October 2020].

IEA. 2021a. Driving Down Methane Leaks from the Oil and Gas Industry, Paris, FR; International Energy Agency (IEA). Available:’

IEA. 2021b. Methane Tracker 2021, Paris, FR; International Energy Agency (IEA). Available:’

National Academies of Sciences, E. & Medicine 2018. Improving Characterization of Anthropogenic Methane Emissions in the United States, Washington, DC, The National Academies Press.

OGCI. 2018. Oil and Gas Climate Initiative sets first collective methane target for member companies [Online]. New York, NY, USA: Oil and Gas Climate Initiative (OGCI). Available: [Accessed June 2020].

Shell. 2018. Why shell has set a methane target [Online]. The Hague, NL: Royal Dutch Shell Available: [Accessed June 2020].

Xu, M., Aizhu, C. & Jacob-Phillips, S. 2020. China’s CNPC targets 50% slash in methane emission intensity by 2025. Reuters, 2 July 2020.

By Dr Jasmin Cooper

Research Associate, SGI

Satellites – The Future of Methane Measurement?

Author: Luke Dubey, Research Assistant, Sustainable Gas Institute


Methane satellite


Methane is the second most important greenhouse gas after CO2. While emissions are far lower than CO2 it has a far higher global warming potential and so is responsible for 25% of today’s anthropogenic climate forcing (Myhre et al., 2013). Methane is the main constituent of natural gas, which is important due to the increasing use of natural gas as a transition fuel. Measuring and estimating emissions from the natural gas supply chain is difficult due to methane being odourless and colourless, and emissions being widespread and intermittent. Should the emission rate of methane be higher than currently estimated the climate benefits of gas relative to coal could be wiped out.

How are emissions measured

Methane emissions from the natural gas supply chain are currently estimated using either bottom-up methods, such as handheld devices and mobile laboratories, or top-down methods such as aeroplanes and satellites. A current issue is that bottom-up methods tend to estimate lower emission rates than top-down methods, even in the same area, and it is not clear whether one is under or another over-estimating emissions.

Satellites have been used for detecting and measuring methane for 20 years. During this time their technology has improved massively, largely by lowering minimum detection limits and increasing resolution. As their technology has improved, their potential role in the natural gas industry has been realised. It is widely hoped they will be able to provide comprehensive coverage, detecting all emissions in an area (which may sometimes not allow access), while returning daily, providing constant measurements. This is highlighted within the EU’s methane strategy, which promotes the Sentinel 5P satellite as capable of measuring global emissions (European Commission, 2020).  However, there are many reasons why satellites might not be up for the task just yet, while still having immense potential in the future.

Limiting factors of satellites

1.      Cloud cover

Satellites have a few issues that are not widely enough discussed, the first being non-detectable pixels. A pixel is the base unit a satellite reports data in, these range from 60km2 for Envisat to 7km2 for Sentinel 5P all the way down to 50m2 for GHGSat. There are many factors that can cause a no detect in a pixel, such as aerosols, albedo and terrain, but the most important is cloud cover. Spectrometers onboard the satellites are what measure the methane; there are many ways to do this but a common one is using sunlight that is backscattered from the earths surface into the spectrometer. The absorption peaks are then analysed and the total concentration of methane in the column is outputted (Jacob et al., 2016). It is clear then how clouds could interfere with this process, with thin clouds causing too much noise for accurate results and thick clouds completely blocking out the sunlight. Many places that produce gas are cloudy virtually year-round (Russia, Canada), meaning there is no way to measure every day of the year with many areas having at best a couple days coverage per pixel per year. Technology has improved over time and will continue to do so, and new methods of reducing the noise from low cloud coverage have been developed, but there is still a long way to go.

2.      Minimum detection limits

A second issue is the minimum detection limits (MDL) of satellites. The MDL is a consequence of the uncertainty within the satellite’s instruments. This will lower as technology improves, and it is possible to reduce over repeated measurements. However, many of the emissions from natural gas are low level and spread out, such as from wells, meaning satellites are unlikely to be able to discern these from the background noise. The saving grace of the MDL is that emissions from natural gas follow a superemitting profile, where a few high emitting sources are responsible for the majority of emissions (Brandt et al., 2016). These are far more likely to be detected by the current crop of satellites and have been a common use of satellites thus far.

3.      Time of overpass

Another aspect of satellites that does not receive enough, if any, attention is the time of overpass. This is fundamentally important when measuring emissions from intermittent sources prevalent across the natural gas supply chain. Should a large emission occur immediately before an overpass the methane will have no time to disperse, increasing the likelihood it is above the MDL and detected. Should the same emission happen hours before an overpass, there is a long time for winds to disperse the emission into nearby pixels, or even distant pixels if long enough has passed. This results in no detection happening and zero emissions being attributed to the pixel. Conversely, if the emission rate detected in the first scenario was extrapolated up to a daily or yearly average, it would greatly overestimate total emissions. Increasing the number of days measured would reduce this effect, or having several satellites working in tandem, measuring at different times of day would help solve the issue.

Newer satellites

The counter to some of the issues raised is in the newest crop of ‘paid for’ satellites. Where the data is not freely available online, but private institutions pay for access, such as GHGSat. These satellites have far higher resolution and lower MDLs. The higher resolution increases the likelihood of an individual pixel being cloud free (chance of no clouds in one of 10,000 100m2 pixels or one 10km2 pixel). However, I believe these satellites play a different role, more comparable to an aeroplane than a traditional satellite. These satellites do not have the ability to globally track emissions daily, but target specific facilities. A hope is that these satellites could work in tandem with more traditional satellites, where one would scan the globe and detect an area of interest, and the other then has a more detailed look. All of this being possible rapidly, stopping hidden emissions far quicker than ever before. With the recent launch of GHGSat C (Iris) and the upcoming launch of MethaneSat this seems a very real possibility.


So what’s the role of satellites now and in the future? Currently satellites are useful for research, but uncertainties are too high for commercial use in the most part. However, satellites can currently play a very helpful role in locating superemitters. As technology improves satellites will become more useful, this will be aided by more satellites coming online, working in tandem to mitigate some of the limitations. Satellites have the potential to comprehensively measure emissions globally at the drop of a hat, this potential has received, and deserves, the time and investment fitting of such a game changing climate change technology. I am hopeful in the near future satellites will be the primary way of measuring methane globally.

BRANDT, A. R., HEATH, G. A. & COOLEY, D. 2016. Methane Leaks from Natural Gas Systems Follow Extreme Distributions. Environmental Science & Technology, 50, 12512-12520.

EUROPEAN COMMISSION. 2020. EU Methane Strategy [Online]. Available: [Accessed 6/1/21 2021].

JACOB, D. J., TURNER, A. J., MAASAKKERS, J. D., SHENG, J., SUN, K., LIU, X., CHANCE, K., ABEN, I., MCKEEVER, J. & FRANKENBERG, C. 2016. Satellite observations of atmospheric methane and their value for quantifying methane emissions. Atmospheric Chemistry and Physics, 16, 14371-14396.

MYHRE, G., SHINDELL, D., BRÉON, F. M., COLLINS, W., FUGLESTVEDT, J., HUANG, J., KOCH, D., LAMARQUE, J. F., LEE, D., MENDOZA, B., NAKAJIMA, T., ROBOCK, A., STEPHENS, G., TAKEMURA, T. & ZHANG, H. 2013. Anthropogenic and natural radiative forcing. In: STOCKER, T. F., QIN, D., PLATTNER, G. K., TIGNOR, M. M. B., ALLEN, S. K., BOSCHUNG, J., NAUELS, A., XIA, Y., BEX, V. & MIDGLEY, P. M. (eds.). Cambridge, UK: Cambridge University Press.

Author: Luke Dubey, Research Assistant, Sustainable Gas Institute

The Role of Public Perception in Carbon Capture and Storage (CCS) Projects: Perspectives for Brazil

Author: Karen L. Mascarenhas 

1. Carbon Capture and Storage (CCS) context

Energy is one of the primary means that supports modern life, either to enable industrialization of goods, the provision of services or even to meet the daily needs of the citizens, such as transportation, housing, work, food and entertainment. Alongside the demand for energy efficiency, changes in the composition of the local and the global energy matrix are increasingly advancing towards cleaner and renewable energy sources, motivated mainly by the planet sustainability and climate change containment.

These concerns are supported by two broad international pacts settled in 2015: the Paris Agreement and the launch of the Sustainable Development Goals by the United Nations.

In Brazil, the transition of the energy matrix requires, initially, a gradual reduction in the use of fossil fuels with a high carbon dioxide (CO2) footprint, switching to the use of natural gas and, later, biogas, solar, wind and hydrogen as sustainable sources of energy production. While the energy demand is greater than the capacity to supply it through renewable sources, natural gas, as one of the fossil fuels with the lowest emission of greenhouse gases, is seen as an alternative to support this transition, offering the potential to provide cleaner and more affordable energy for a large number of people in the country.

The geological formation of the pre-salt basin on the coast of five Brazilian states enables the extraction of large quantities of oil and natural gas, the latter with a high concentration of CO2. The pre-salt has specific characteristics that allow the creation of saline cavities capable of storing large amounts of CO2, avoiding ventilation into the atmosphere. Technologies are being developed to separate methane (CH4), CO2 and other gases in caves using a gravimetric method and other innovative technologies, keeping the captured CO2 without the need to re-inject it, and preventing its release into the atmosphere. These technologies are called Carbon Capture and Storage (CCS), or Carbon Capture Usage and Storage (CCUS) when it also involves the use of carbon for other ends.

Similar technologies adopted in a renewable area, such as the capture of CO2 released by the fermentation process in the ethanol production, are creating conditions for the capture, use and storage of carbon bioenergy (BECCUS). This technology can evolve to a negative CO2 footprint process, since the emissions from the processing, distribution and, finally, combustion of ethanol are neutralized through their absorption by the sugarcane plantation. In other words, the cycle becomes sustainable as the plants in the photosynthesis process absorb the gases released by the ethanol production process, and any reminiscent CO2 can be stored in underground reservoirs or employed as raw material for the production of other high-added-value products.

2. Social challenges in CCS implementation

However, the implementation of projects based on CCS technologies cause changes in the territory, as they imply in the creation or use of underground reservoirs on land (onshore) or underwater in the ocean (offshore), impacting the environment, their living ecosystems and the local community. Besides, CCS, CCUS, and BECCUS are not yet known by other agents outside the specific academic and industry segments that study or manage these technologies. Previous experiences of implementing projects of this nature have demonstrated the relevance of considering the perception and acceptance of government, media, society, other academics and industries not directly related to such technologies. Their reactions can emerge from irrational bias, through strong opinions, even if they have no information about the risks or benefits involved.

Therefore, public perception can be one of the critical barriers to the deployment of CCS projects. Local communities’ opposition has shown to derail demonstration plants in some of the first projects that aimed to store CO2 onshore as the Barendrecht Project in the Netherlands, and Beeskow in Germany

3. Public perception of CCS technologies in Brazil

In Brazil, studies on public perception related to CCS are still scarce, as only three were identified. The most comprehensive concerns a CCS onshore field study at the Recôncavo Basin in the state of Bahia, an outstanding region of oil exploration.  The qualitative research was conducted with ten communities located in prospective areas for CCS implementation who did not have any knowledge of the concept. The main outcomes show that people that have a previous relationship with oil companies are best equipped to identify benefits or disadvantages, that trust in government and private companies can enhance their support of such projects, and that further investigation is imperative as Brazil is a vast country with great cultural diversity, making it hard to define a national perception of CCS as each region has its singular peculiarities and views.

Public perception studies within developing countries are challenging as the low level of fundamental education impacts on the citizens’ capacity to understand complex concepts like climate change. This tends to be the profile of inhabitants in Brazilian regions where CCS projects could be implemented.

Pioneering studies in public perception in Brazil are under development in the Research Centre for Gas Innovation (RCGI), headquartered at the Polytechnic School of the University of São Paulo, financed by the Research Funding Agency of the State of São Paulo (FAPESP), in partnership with the private company Shell.

The RCGI started its activities in January 2016 and currently has 46 projects focused on innovation, aiming at the sustainable use of natural gas, biogas, hydrogen and the reduction of CO2 emissions worldwide to contribute towards climate improvement and sustainability.

The initiative to research public perception emerged from the intention of complementing the technical and legal research carried out in the RCGI with the social and human dimensions, in a multidisciplinary approach. This process aims to understand the public perception of all agents, as government representatives, media, academia, industry, NGOs and society, building trustful relationships and supporting the analysis of potential CCS projects in the country.

Author: Karen L. Mascarenhas – Imperial College London, University of São Paulo, Research Centre for Gas Innovation (RCGI)

Net-Zero Emissions by 2050? Together We Can….

Author: Rumbi Nhunduru

Since 2014, the Sustainable Gas Institute at Imperial College London has been providing world leading thought leadership and interdisciplinary research on the role of natural gas, hydrogen and biogas/biomethane in future low carbon energy systems. This year, the speaker for the 2020 Annual Lecture on 10 December will be Professor Maroto-Valer who is leading the development of the UK Industrial Decarbonisation Research and Innovation Centre (IDRIC). Professor Maroto-Valer will be speaking about industrial decarbonisation and discussing the role of gas for a green economic recovery. And now, more than ever, as we are starting to emerge from the COVID-19 crisis, decarbonisation is critical for green economic recovery. But, can we really achieve net zero targets?

Since the turn of the First Industrial Revolution in the 18th century, continuously rising greenhouse gas emissions, primarily from the combustion of fossil fuels, have been a cause for concern and the main fuelling factor for climate change and global warming. Consequences of atmospheric greenhouse gas emissions, (more specifically, carbon dioxide-CO2) that have already started to be experienced globally include rise in sea levels, melting of ice caps and glaciers and increased occurrence of severe weather events, such as droughts, heatwaves and flooding. In the UK for example, the occurrence of extreme weather events has increased in recent years with the highest ever temperature of 38.7°C having been recorded last year (2019) [1]. More recently, through June to August 2020, the country experienced heat waves with temperatures in excess of 30°C. The UK has also experienced an increase in heavy rainfall and flooding.

The notion that we need to make urgent, drastic and fair measures to reduce greenhouse gas emissions and prevent global warming has gained traction and momentum in recent years. Pressure has been mounting on governments worldwide to take immediate action. At the Climate Ambition event on the side-lines of the UN Climate Change Conference COP 25 in Madrid (Spain), 73 UNFCCC parties, 14 regions, 398 cities, 768 businesses and 16 investors agreed to work together towards achieving net-zero CO2 emissions by 2050[2]. Whilst other major economies such as Japan and France have set targets to achieve net zero emissions by 2050, in June 2019, the UK became the first major economy to take the lead and pass legislation to achieve net zero greenhouse gas emissions by the year 2050 [3]. According to the International Energy Agency’s (IEA) 2020 World Energy Outlook report, to achieve the goal of carbon neutrality, emissions must peak in 2020 and drop by over 40% by the year 2030 [4]. The U.S is one of the the world’s largest greenhouse gas emitter thus its contribution will also be highly significant if we are to meet the net zero emissions target.  In June 2017, the then US president, Donald Trump, announced that the US would be withdrawing from the 2015 Paris Climate Change Agreement. In his electoral campaign, the newly elected president of the United States, Joe Biden, stated that it will be in his agenda to re-join the Paris Agreement in the early years of his presidency. With the UK set to host the 26th UN Climate Change Conference of the Parties (COP26) in November 2021, all eyes will be focused on the US.[5]

Achieving net zero greenhouse gas emissions by 2050 will require large scale investment and transition to the use of clean, renewable energy as well as adopting and implementing new technologies such as hydrogen and carbon capture, utilisation and storage (CCUS).  Meeting the ambitious target of the ‘Race to Zero’ campaign requires collective, collaborative action from stakeholders across industry, government and academia. In the Research Centre for Carbon Solutions (RCCS) at Heriot-Watt University, we have also been playing our part in contributing to the masterplan to achieve net-zero emissions by 2050. Our research takes a systems approach ensuring the integration of different technologies at systems level, particularly for sectors difficult to decarbonise. Our projects include all aspects of the CCUS chain from capture through to transport, utilisation and storage, as well as hydrogen and negative emissions technologies.

In March 2020, the UK government announced that a budget of £800m has been set aside for the deployment of CCS infrastructure. This CCS Infrastructure fund will put into action the large-scale plan to capture CO2 from major industries and transport it by pipeline to be stored in depleted oil and gas reservoirs under the seabed in the North Sea [6]. On the 17th of  November 2020, the UK’s prime minister, Boris Johnson, unveiled a ‘10-point plan’ backed by £12bn and aimed at supporting and accelerating the process of decarbonising the UK and initiating a ‘Green Industrial Revolution’. The plan includes an extra £200m of funding to develop at least two carbon capture clusters by the mid-2020s in addition to the £800m budget set aside in March 2020 for CCUS and hydrogen technology deployment. Another two clusters are also set to be developed by 2030.  This move will make the UK a global leader in terms of  CCUS and hydrogen technology [7]. With the UK set to decarbonise, potential CCUS deployment sites include Aberdeen, Liverpool, Port Talbot, Scunthorpe, Southampton, Nottingham, Grangemouth, Teesside and Humberside. The ‘Humber’ is the UK’s most carbon intensive industrial cluster with over 55,000 people employed in manufacturing and other energy intensive industrial sectors. Decarbonising the Humber would undoubtedly have a highly significant impact. This will be carried out in conjunction with key players in the energy sector and is set to result in the development of Europe’s largest joint hydrogen production and carbon capture project by 2026 [6].

As the UK edges closer towards CCUS deployment, it is important to harness all available talent in this transition and nurture the next generation of engineers and scientists to deliver the energy transition. In this regard, an Early Career Professionals Forum specifically for CCUS, complementary to the already established UK CCUS Council was recently established and launched by the UK Government’s Department of Business, Energy and Industrial Strategy (BEIS). The aim of this forum is to provide a platform for professionals in the early stages of their career who are working in the CCUS sector to provide their views on key strategic issues to do with CCUS deployment as well as to drive forward efforts to meet the net zero target by 2050. The 26th UN Climate Change Conference of the Parties (COP26) will be held in November 2021 under the theme #Together for Our Planet. On a personal level, as the Heriot-Watt RCCS representative in the CCUS Early Career Professionals Forum, I feel highly honoured to be able to play a small part in contributing to the masterplan through engagement with other members of the forum and other relevant stakeholders from government, industry and academia.

As the saying goes, “Great things are done by a series of small things brought together- Vincent Van Gogh”. Net Zero by 2050? Indeed, together we can!

by Rumbidzai Nhunduru

Research Centre for Carbon Solutions (RCCS), Heriot-Watt University



  1. A.Walker. Jun 2019. Met Office Confirms New UK Record Temperature of 38.7°C. The Guardian.,%2C%20Kent%2C%20in%20August%202003
  2. United Nations Framework Convention on Climate Change (UNFCC). External Press Release. Climate Ambition Alliance: Nations Renew their Push to Upscale Action by 2020 and Achieve Net Zero CO2 Emissions by 2050.
  3. GOV.UK.
  4. International Energy Agency (IEA). World Energy Outlook Report 2020.

  1. Q. Schiermeier. The US has left the Paris climate deal — what’s next? Nov 2020. Nature Research Journals.
  2. D. Laister. Mar 2020. £800m Carbon Capture Pot Brings Humber’s Biggest Budget Wish Closer to Home. Business Live.
  3. M. Burgess. Nov 2020. UK PM backs CCS and hydrogen in 10-point plan. Gasworld.

Seven easy-peasy ways to make Brazilian ethanol industry more sustainable

Author: Dr Pedro Gerber Machado, Researcher

Clickbait! The truth is, it is not easy. The ethanol industry and several academics have created a storyline for Brazilian ethanol: it combats climate change by producing renewable energy, promotes rural development creating jobs and represents one of the biggest prides for the country when it comes to national industry. Are they right? Well, in parts. Their focus on the positive side of ethanol production is purposeful, naturally. Still, many aspects of the industry need improvements ASAP. Here, I discuss 7 points that would help ethanol become MORE sustainable. It is essential to highlight the word MORE, simply because sustainability is not a point of arrival, but the road itself. Nothing is sustainable, only on the road to becoming more sustainable, but this is subject for another post.


The potential for biogas production in Brazil is well known due to the country’s economy based on agriculture. What is not so well known is that considering municipal solid waste, agriculture and ethanol industry, biogas could substitute all of the natural gas consumed in the country in one year, plus another 25% to spare (considering 90% methane). Today, Brazil only produces 1.5% of its potential. Still, the increase in biogas volume in the last couple of years has reached 36% p.a., showing that it is getting momentum within the energy and electricity sectors in the country. The most significant potential for biogas production is in ethanol mills, using vinasse as feedstock, a residue from ethanol distillation. Not only the potential is enormous, but the costs of biogas production can reach levels cheaper than imported LNG, diesel, and even Brazilian natural gas1.

Biogas production increases the share of renewable energy in the country’s electricity matrix. It could also free-up the lignocellulosic residues (today mostly sugarcane bagasse used for electricity generation) for other more advanced products, which brings us to our next 2 points.

Second-generation ethanol

Second-generation ethanol is ethanol produced from lignocellulosic biomass. In the ethanol industry, bagasse and even sugarcane straw brought from the field are sources of lignocellulosic material. Up to now, only 32 million litres of second-generation ethanol is produced in Brazil, which evaporates (pun intended) in comparison to the 28 billion litres from sugarcane juice fermentation (first-generation)2. With a target of 2.5 billion litres of second-generation ethanol produced in 2030, the road is long, but necessary nonetheless. The use of residues for ethanol increases the production per hectare of land and consequently decreases direct and indirect land-use change. In combination with biogas, each mill could increase ethanol production from residues while maintaining its electricity generation. Besides, processing bagasse generates other opportunities than second-generation ethanol, especially from its lignin fraction, considered the only biologic substitute of fossil-based aromatic chemicals, for example.

Biobased chemicals

Biobased chemicals are often praised for reducing greenhouse gases (GHG) emissions and increasing the added value of biomass. In reality, producing chemicals to reduce GHG emissions in Brazil is like having cancer and an ingrown toenail and visit the doctor for the toenail. However, hundreds of technologies and products derived from biomass, residues or not, in the last two decades have proven to be not only technically feasible but also economically attractive, which should be seen by mill owners and investors as an opportunity. Many times, authors (including myself) compare second-generation and biobased chemicals with electricity as if it was one or the other. But when you look at the national chemical market, the volume would mean very few average-sized mills, and it would not pose threats to second-generation ethanol. For example, approximately 30 sugarcane mills of 2 million tonnes of sugarcane annually could supply all propylene consumed in the country in a year3.

Small-scale mills

With average and large-sized mills producing second-generation and biochemicals, small-scale plants should gain space in fermentation mills. Either for self-consumption or the ethanol market, ethanol could represent a new source of income for farmers and cooperatives, increasing the social pros of ethanol. The implementation of small-scale mills will not be possible only based on the market, due to lower economic viability of small-scale mills and specific policies would need to be created to reduce ethanol production concentration in the hands of few investors4.

Social responsibility

The ethanol industry in Brazil has used corporate social responsibility communication as a way to highlight efforts to portray itself as a clean source of energy. Analysing past communications, one will find the preference to discuss agro-environmental themes. When it comes to social themes, the interest is timider. Significant education and labour conditions programs have been dropped by the ethanol industry, leaving a gap in social change. The National Commitment for the Improvement of Labour Conditions in Sugarcane Production, launched in 2009 and abandoned in 2013 due to severe violations of labour practices in companies that had gained their social seal of conformity, was a trilateral agreement between the government, private sector, and labour unions to promote the adoption of better labour practices in the sugar and ethanol industries. The retraining program “Renovação” by UNICA (Sugarcane Industry Union), which aimed at retraining laid-off sugarcane cutters following harvest mechanisation, ran from 2010 until 20135. It retrained a disappointing 5 thousand people (of course the program was praised as a success), compared to the 128 thousand jobs lost in sugarcane cultivation in the last ten years. UNICA also stopped publishing its sustainability report in 2010, which does not help with transparency when it comes to the social issues that surround the sugarcane industry6.

For the ethanol industry to become more sustainable, the lives of the people directly and indirectly affected by sugarcane production need to be improved, and the industry has an essential role in this development. Education, the health of local communities, labour conditions and decent income have to be prioritised in long-term programs and planning by the industry.

Integrate food/forest/energy systems

It is time to start rethinking agriculture based on monoculture and harmonising forestry and agriculture practices is fundamental to improve wildlife protection and increase contributions to climate mitigation. It can be accomplished in many ways, either with spatial approaches or temporal approaches, like crop rotation. The problem is that the productivity of integrated systems is still contested compared to monocultures. This requires research assessments across multiple systems, and policies to incentivise landowners and farmers to engage in diverse land use management systems7.

ZERO deforestation in Brazil

Since 2008 when Searchinger most famously brought to light the problem of indirect land-use change (ILUC) caused by biofuels8, Brazil has spent millions of dollars in research to refute the idea. The truth is it makes sense, regardless of the actual level of deforestation indirectly caused by biofuels. In the last ten years, Brazil lost 12 million hectares of natural forests to pastures and pastures lost 1.1 million hectares for sugarcane9. You need incredibly complex models to determine the exact piece of land that ultimately ended-up with sugarcane. Still, for every 100 hectares of natural forests lost for pastures, nine were converted to sugarcane. To cut ILUC problem at its root (again, pun intended) Brazil should seize deforestation. On top of that, the country gains a more sustainable agriculture as a whole, and, of course, maintain the utterly important ecosystem services provided by our natural forests.

There you go, my seven ways to make Brazilian ethanol more sustainable. All of these require research, investments, policies, regulation and law enforcement and, on top of that economic attractiveness. I didn’t say it was easy, did I?


  1. Nota Técnica: N° 002/2010 – Panorama do Biogás no Brasil em 2019; Foz do Iguaçu, 2020;
  2. Barros, S.; Rubio, N. Biofuels Annual – Brazil; USDA; São Paulo, 2020;
  3. Machado, P.G.; Walter, A.; Cunha, M. Bio-based propylene production in a sugarcane biorefinery: A techno-economic evaluation for Brazilian conditions. Biofuels, Bioprod. Biorefining 2016, 10, 623–633, doi:10.1002/bbb.1674.
  4. Mayer, F.D.; Feris, L.A.; Marcilio, N.R.; Hoffmann, R. Why small-scale fuel ethanol production in Brazil does not take off? Sustain. Energy Rev. 2015, 43, 687–701, doi:10.1016/j.rser.2014.11.076.
  5. Benites-Lazaro, L.L.; Giatti, L.; Giarolla, A. Sustainability and governance of sugarcane ethanol companies in Brazil: Topic modeling analysis of CSR reporting. Clean. Prod. 2018, 197, 583–591, doi:10.1016/j.jclepro.2018.06.212.
  6. Relação Anual de Informações Sociais (RAIS). Access only with login at
  7. Richard, T.L.; El-Lakany, H. Agriculture and forestry integration. In Bioenergy & Sustainability: Bridging the gaps; SCOPE 72, 2015; Vol. 72, pp. 1329–1341 ISBN 978-2-9545557-0-6.
  8. Searchinger, T.; Heimlich, R.; Houghton, R.A.; Dong, F.; Elobeid, A.; Fabiosa, J.; Tokgoz, S.; Hayes, D.; Yu, T.-H. Use of U.S. Croplands for Biofuels Increases Greenhouse Gases Through Emissions from Land-Use Change. Science (80-. ). 2008, 319, 1238–1240, doi:10.1126/science.1151861.
  9. Estatisticas uso da terra. Available online:


By Dr Pedro Gerber Machado, Researcher

Pedro’s biography

Blog: Productivity Pathways for Meeting Farming Demand Sustainably

Matheus Mansour is a final-year undergraduate student in Industrial Engineering at the University of Sao Paulo’s Polytechnic School. Matheus is from Brazil and is interested in statistics, operations research, machine learning and tech businesses in general. He is currently working on his capstone project where he applies neural networks to build a forecasting model for farming production in Brazil. In this blog, Matheus writes about this project and explains how its methodology can be used as a step to guide public policy towards a more sustainable future worldwide. 


Much has been said about sustainability over the past 30 years. Starting from the basic definition of satisfying the needs of the present without compromising the capacity of future generations of satisfying their own needs, there are many aspects that must be taken care of to ensure an overall positive outlook for the generations to come.

One such aspect concerns taking action to combat climate change and its impacts. It is known that the current climate change is mainly caused by human activity (i.e. by people burning fossil fuels and converting land from forests to agriculture, thus releasing carbon dioxide into the atmosphere). Regarding the latter, the incentives for such behaviour are plentiful: with an ever-growing population and limited land supply, natural coverage areas are being deforested in order to grow crops and meet the consequential rising farming demand. Specifically in Brazil, for instance, it is estimated (FAO) that 20% of the Amazon rainforest has been lost to deforestation over the past 50 years.


In addition, more than two thirds of the national gross CO2 emissions come from land use, land-use change and forestry (FILHO et al., 2010). As carbon dioxide is one of the main drivers of climate change, an appropriate national-level set of public policies to avoid deforestation is thus expected to bring high dividends. This has to be done, however, while still allowing the productive sector to meet agricultural and livestock demand of an expanding economy so as to not harm the country’s development.

If deforestation is to be avoided without compromising on a reduced output and exports, it is necessary to increase farming productivity. This, however, cannot be done as the need arises. Public policies are necessary and should be planned well ahead. It is necessary to identify the needed and sufficient improvements in productivity that allow for meeting future farming demand with the current levels of land supply available for agriculture and pasture. In case of assessing possible reforestation policies, it is also necessary to address the consequent needed increase in productivities that will lead to the demand being met.

Our project is then constructed in two main phases. First, we need an accurate mid to long-term projection for the baseline output of the main agricultural crops and livestock in Brazil, with occasional deforestation. This will serve as a means to assess the natural development of internal and external farming demand to unfold. Since we wish to assess how a restricted (by policy) land supply will affect total output in the future, it is necessary to build a model relating those variables, whose relationship is by no means linear, as total output depends on a range of different internal and external factors. While other models use static methods such as time series to make output forecasts, they do not allow this scenario simulation, which is the core of our project. We therefore use neural networks to capture those intrinsic relationships between inputs and farming output. This way, we are able to simulate what would happen to production if we tweak the input drivers by policy-making to achieve our sustainability goals.

Lastly, we are left with the task of assessing an optimal set of productivity gains necessary for future scenarios without deforestation and with reforestation. This will hopefully be an essential tool to guide public policy today towards a future both sustainable and prosperous.

Student Project – Agricultural productivity pathways to avoid deforestation in Brazil: application of neural networks

SGI undergraduate student Matheus Mansour has been working on a project relating to agricultural productivity pathways to avoid deforestation in Brazil.

Many models are created with the objective of estimating some kind of economic output, either by a country’s industry or agricultural sector. Time series, general and partial equilibrium models and many other methodologies have been used in the past. However, with the advent of new deep learning methods, powerful tools could be of great use in planning and economic forecasting. In Brazil, a considerable share of GDP is produced by the livestock and agriculture sectors, which have considerable environmental impacts on land use-related issues such as deforestation and biodiversity loss. To avoid these impacts, it is necessary to plan ahead and identify the necessary improvements in productivity for the long ran, if deforestation is to be avoided.

Using data from the last 35 years and 11 of the most important agricultural crops and livestock in Brazil, neural networks will be trained and used as basis for the analysis of scenarios of productivity gains necessary to avoid deforestation in the country and evaluate how reforestation could affect the supply of future agricultural demand. This project is being developed in partnership with Prof. Celma Ribeiro of University of São Paulo, Brazil.

Student Project – Inserting lignin in the sugarcane mills product portfolio: A study using robust optimization approach

SGI PhD student Raphael Dutenkefer has been working on a project looking at insertion of lignin in the sugarcane mills product portfolio.

The use of residues from the sugarcane in industry has been of considerable interest in the last decade. There is a great interest in producing high added value products from residues that today are used solely for the generation of electricity. Lignin, one of the components of lignocellulosic residues derived from sugarcane, is a class of complex organic polymers that can serve as feedstock for the production of many chemicals, materials and even energy carriers. However, its processing technologies are still in an immature technological phase and need further development to become an economically viable option for producers and consumers.

In partnership with Prof. Celma Ribeiro of University of São Paulo, Brazil, this project intends to deeper understand how lignin could improve the economic efficiency of sugarcane mills and what are the best processes being developed today, from an economic perspective. Using a methodology to define the best portfolio for a certain range of products, this project intends to evaluate the investments, maintenance costs, selling price and efficiencies necessary to make lignin a viable feedstock for materials, chemicals and energy carriers.