Greenhouse Gas Emission Reduction Potential Research Articles

Evaluating greenhouse gas emission reductions by using solar water heaters: A case of low income households in Ekurhuleni, South Africa

This work evaluates and analyses the Greenhouse Gas (GHG) emission reduction potential of Solar Water Heaters (SWH) in Daveyton, in Ekurhuleni. As an energy intensive country, with its energy mix dominated by fossil-fuel energy sources, South Africa is among the largest emitters of GHGs globally. Consequently, the country made commitments to substantially reduce its carbon footprint from the energy sector, through renewable energy initiatives. A solar water heater programme was subsequently introduced as an initiative to reduce GHG emissions in the residential sector. Objectives of the study were to determine the amount of energy saved and GHG emission reduction through the installation of SWHs; to determine the efficiency and sufficiency of SWHs for the average family; and to determine the contribution of SWHs towards reduction of GHG emissions. These objectives were achieved by conducting a survey in low-income households that were piloted for the SWH installation programme in Daveyton, Ekurhuleni. The findings of the study suggested that a total saving of 89.74 kWh of energy per day and reduction of 63.1 kg of carbon dioxide (CO2) equivalent were achieved through the SWH programme for the entire sample area per day. In conclusion, solar water heating in domestic sector of Ekurhuleni could potentially reduce reliance of households to fossil fuels, thus reducing GHG emissions.

Greenhouse gas emission reduction potential and cost of bioenergy in British Columbia, Canada

The Canadian province of British Columbia (BC) provides an informative case study of bioenergy development, because it relies heavily on fossil fuels but has enormous bioenergy potential. We have examined the potential contribution of bioenergy to reducing BC's GHG emissions. The approach of combining life cycle assessment and economic evaluation to prioritize options should be applicable generally. Biomass availability, including forestry resources, agricultural waste and municipal solid waste, is estimated. Through simplified Life Cycle Assessment, GHG reduction potential of biogas, bioethanol, biofuels from hydrothermal liquefaction, and district heating are quantified, along with the associated GHG reduction costs. The analysis shows that existing biomass resources could yield 110–176 PJ per year, reducing GHG emissions by 13.0–15.7%. Bioenergy from waste streams is already cost-effective and should be prioritized in the short term. However, bioenergy from forestry resources, especially conversion to liquid biofuels, is prohibitively expensive, with GHG reduction cost exceeding CAD $300/t CO2-eq. The total extra cost required to achieve full utilization of BC's biomass resources is estimated as 0.8–2.4 billion dollars. To close the cost gaps between bioenergy and fossil fuels, both technological improvement and external cost adjustment through measures like carbon taxation will be needed.

Technical, financial, and environmental feasibility of solar water heater for residential, commercial, and industrial application: A theoretical approach

This paper aims to evaluate the techno-economical and environmental viability of the solar water heater (SWH) system applications in residential, commercial, and industrial sectors of India through the RETScreen Expert Clean Energy Management Software. The three different geographical locations have been selected, namely Leh, Amethi (Jais), and Ludhiana districts for residential, commercial, and industrial case studies respectively. The three different locations have been chosen for each case study to exhibit the applicability and performance of SWH systems at different geographical locations of the Indian climate. The performance of SWH models is evaluated by a solar fraction (SF). The average values of SF obtained are 74, 64.48, and 13 correspondings to residential, commercial, and industrial models. It is also found that the cumulative value of greenhouse gas emission reduction (GHGR) potential for residential, commercial, and industrial sectors is 155.9 tCO2, 2419.3 tCO2, and 492.3 tCO2 per year for 25 years of project life. The cumulative value of the annual energy saving of each model is also calculated as 111.3 MWh, 1728.6 MWh, and 313.8 MWh. The financial viability of the models is presented by parameters like Simple Payback Period (SPP), Equity Payback Period (EPP), Internal Rate of Return (IRR), and Modified Internal Rate of Return (MIRR). The average value of SPP for models is 4.83 yr, 8.99 yr, and 3.90 yr corresponding to residential, commercial, and industrial models. The average value of the IRR of each model is also as 30.36%, 27.89%, and 38.77%.

Comparison of the Greenhouse Gas Emission Reduction Potential of Energy Communities

In this research, the greenhouse gas (GHG) emission reduction potentials of electric vehicles, heat pumps, photovoltaic (PV) systems and batteries were determined in eight different countries: Austria, Belgium, France, Germany, Italy, the Netherlands, Portugal and Spain. Also, the difference between using prosuming electricity as a community (i.e., energy sharing) and prosuming it as an individual household was calculated. Results show that all investigated technologies have substantial GHG emission reduction potential. A strong moderating factor is the existing electricity generation mix of a country: the GHG emission reduction potential is highest in countries that currently have high hourly emission factors. GHG emission reduction potentials are highest in southern Europe (Portugal, Spain, Italy) and lowest in countries with a high share of nuclear energy (Belgium, France). Hence, from a European GHG emission reduction perspective, it has most impact to install PV in countries that currently have a fossil-fueled electricity mix and/or have high solar irradiation. Lastly, we have seen that energy sharing leads to an increased GHG emission reduction potential in all countries, because it leads to higher PV capacities.

Carbon Handprint: Potential Climate Benefits of a Novel Liquid-Cooled Base Station with Waste Heat Reuse

The novel life cycle assessment (LCA)-based carbon handprint indicator represents a potential carbon footprint reduction that producers/products create for customers who use the(ir) product instead of a baseline product. The research question is how to consider a situation in which multiple customers use a product for different purposes to provide a carbon handprint quantification and the associated communication. The study further provides new insight into the greenhouse gas (GHG) emissions reduction potential within the mobile telecommunications and energy sectors. The carbon handprint of a novel Finnish liquid-cooled base station technology is quantified. The liquid-cooled base station provides a telecommunications service and waste heat that is recoverable through the cooling liquid for heating purposes. The baseline solutions are an air-cooled base station, and district and electrical heating. The liquid-cooled base station creates a carbon handprint, both through energy savings in telecommunications and additional waste heat reuse, replacing other energy production methods. A large-scale climate change mitigation potential through a liquid-cooled base station expansion could be significant. Different supply chain operators’ contributions to the total carbon handprint could be terminologically distinguished in communications to emphasize their roles in a shared handprint. The handprint should be transparently communicated for each customer and function.

Energy Recovery and Greenhouse Gas Emission Reduction Potential of Bio-Waste in the Mediterranean Region of Turkey

Continuous demand for global power generation has increased the attention on renewable energy sources. Biogas is one of the viable options for conversion of organic waste materials into green power and valuable products. In this study, the impact of biogas production from agricultural residues (wheat straw, barley straw, corn stover, cotton residue, olive residue, banana peel, sugarcane bagasse, tomato residue) and municipal solid waste (MSW) on reduction of greenhouse gas (GHG) emissions in Mediterranean Region of Turkey (Antalya, Burdur, Isparta, Mersin, Adana, Hatay, Osmaniye and Kahramanmaraş) has estimated. The results revealed that the Region has 1942.6 million m 3 /year biogas production potential corresponding to 11.11 TWh energy generating capacity. Biogas generation in the Region has annual 27 million tons of CO 2 emission reduction potential to contribute 7.4 % reduction in total GHG emissions in Turkey. Bio-waste is a favorable renewable substitute to energy production from fossil fuels.

Transport oil product consumption and GHG emission reduction potential in China: An electric vehicle-based scenario analysis.

China’s transport sector is facing enormous challenges from soaring energy consumption and greenhouse gas (GHG) emissions. Transport electrification has been viewed as a major solution to transportation decarbonization, and electric vehicles (EVs) have attracted considerable attention from policymakers. This paper analyzes the effects of the introduction of EVs in China. A system dynamics model is developed and applied to assess the energy-saving and emission-reducing impacts of the projected penetration of EVs until the year 2030. Five types of scenarios of various EV penetration rates, electricity generation mixes, and the speed of technological improvement are discussed. Results confirm that reductions in transport GHG emissions and gasoline and diesel consumption by 3.0%–16.2%, 4.4%–16.1%, and 15.8%–34.3%, respectively, will be achieved by 2030 under China’s projected EV penetration scenarios. Results also confirm that if EV penetration is accompanied by decarbonized electricity generation, that is, the use of 55% coal by 2030, then total transport GHG emissions will be further reduced by 0.8%–4.4%. Moreover, further reductions of GHG emissions of up to 5.6% could be achieved through technological improvement. The promotion of EVs could substantially affect the reduction of transport GHG emissions in China, despite the uncertainty of the influence intensity, which is dependent on the penetration rate of EVs, the decarbonization of the power sector, and the technological improvement efficiency of EVs and internal combustion engine vehicles.

Reduction potential of GHG emissions from municipal solid waste incineration for power generation in Beijing

Abstract With rapid economic growth and massive urbanization, China faces the problem of municipal solid waste (MSW) disposal and the pressing need for development of alternative energy. MSW incineration for power generation is playing an increasingly important role in MSW management in China. In order to study the reduction of GHG emissions caused by MSW incineration for power generation, the GHG emissions under the baseline level is calculated by using Clean Development Mechanism (CDM) methodology. Then, the GHG emission reduction is estimated based on the improved upstream-operation-downstream (UOD) framework. Finally, the GHG emission reduction in Beijing is studied and forecasted through grey prediction model and scenario analysis, and the main factors affecting the reduction potential are identified. The results show that the GHG emission reduction target can be achieved through MSW incineration for power generation. Direct and alternative GHG emissions from MSW incineration are the main sources of emissions, while indirect emissions account for a small proportion. The MSW disposal volume, the moisture content of MSW, the installed capacity of biomass energy, the average line loss of power generation and the quantity of fossil fuels consumed by power generation are five important factors that affecting GHG emission reduction potential. It is recommended that the dominant form of waste disposal in China should be replaced by MSW incineration for power generation, and the full classification of MSW needs to be promoted. Furthermore, the installed capacity of biomass energy should be increased and the average line loss of power generation should be reduced.

Energy and greenhouse gas emission reduction potentials resulting from different commuter electric bicycle adoption scenarios in Switzerland

To ensure long-term availability of mobility and to keep the effects of humanity on global climate limited, politics, research, and industry currently search for ways to reduce greenhouse gas (GHG) emissions caused by it. A potential reduction could be achieved by transitioning towards more efficient transport modes, optimally powered by renewable energy. Based on mobility (commutes), population, and weather data from Switzerland, we present a model to compute energy savings due to a (hypothetical) widespread deployment of electric bicycles. In different scenarios, we analyze the dependence of the commuting energy demand on users’ preferences about when to take the bike, such as an aversion to biking on cold and rainy days. Our study shows that GHG emission reductions of up to approx. 10% of the total emissions from diesel and gasoline are possible. In combination with a widespread deployment of electric vehicles, further savings of up to 17.5% could be achieved. In particular, the willingness to drive longer commutes by e-bike influences the potential GHG emission reductions, followed by the willingness to use the bicycle at temperatures below 10°C. Using these results, we identify the spatial energy and greenhouse gas savings potential and thus regions that are particularly suited for e-bike use. The identification of regions with high saving potentials allows for targeted marketing, transition-supporting incentives, or infrastructural changes to maximize the reduction of emissions.

Spatio-temporal distribution of sewage sludge, its methane production potential, and a greenhouse gas emissions analysis

With ongoing economic development and population growth in China, large quantities of wastewater are discharged and substantial amounts of sewage sludge are generated, which is a potential biomass resource for methane production. This study used data from statistics yearbooks and literatures to evaluate the spatio-temporal distribution of sludge generation, potential and distribution of methane production from sludge, and the potential of greenhouse gas (GHG) emissions reduction (PGER) from sludge treatment and disposal in provinces in mainland China. The results showed that a total of 6.03 Mt of dry solids in 2015. The eastern part of the country produced more sludge than that the western part. The standard coal equivalence of sludge was 3.5 Mt, ranged from 0.7 to 399.8 Kt, among the 31 provinces of mainland China. Total sludge could produce 1.27 billion m 3 of methane per year through anaerobic digestion (AD). The distribution of methane density exhibited that the east part was higher than the west part in China. The GHG emissions totaled 18.82 Mt CO 2 -eq as a baseline for the current sludge disposal methods without AD technology. The PGER was 10.77 Mt CO 2 -eq for the sludge disposal routes with AD technology. The sludge disposal for the project route of building material exhibited the highest PGER of 4.24 Mt CO 2 -eq among the disposal methods. As the least GHG emissions method, sludge treated by AD and the residue disposed for land using as fertilizer should be recommended. Our findings provide a sludge disposal reference for the government and industries. For further study, it is suggested to take the co-digestion technology into consideration for sewage sludge to produce methane, which would perform a higher methane production and GHG emissions reduction potential. • A total of 6.03 Mt dry solids of sludge were generated in China in 2015. • Dry sludge with calorific value of 3.5 Mt was generated in 2015. • Methane production potential from sludge was estimated at 1.27 billion m 3 in 2015. • Land application after anaerobic digestion can reduce GHG by 177.7 Kt CO 2 -eq.

Life Cycle Assessment of Straw Solid Particle Molding Fuel Manufacturing Process

Taking a 500,000 t/a straw briquette fuel plant in Baoding area of Hebei Province as an example, this paper establishes a life cycle energy consumption and environmental emission analysis model of straw solid fuel. Based on this model, the energy saving and greenhouse gas emission reduction potential of straw solid particles as typical briquette fuels are quantitatively analyzed. Secondly, the life cycle energy consumption and environmental emissions are analyzed. Finally, from the point of view of energy consumption and environmental emissions, the potential value of environmental impact is calculated by standardization and sensitivity analysis is carried out. The results show that the energy consumption of straw granulation stage (compression molding stage) accounts for the largest proportion in the solid particle manufacturing life cycle, reaching 32.30%. Compared with fossil fuels, solid particles have a large emission reduction advantage, which provides basic data for the utilization of straw solid granular forming fuel.

Determination of Biogas Energy Potential of Aegean Region Based on Animal Waste

Biogas is one the promising sustainable energy options due to high availability of organic wastes. Turkey is an energy importer country and diversification of the energy production with indigenous resources is vital for energy security. In Turkey, agricultural activities and livestock farming have important economic value. Biogas production from anaerobic digestion of organic wastes such as livestock manure is of great importance for renewable energy production and waste management for health and environmental protection. In this study, the animal manure based biogas potential, energy value, greenhouse gas emission reduction potential and organic fertilizer generation capacity of the Aegean Region of Turkey were determined. The region is composed of eight provinces including Afyonkarahisar, Aydın, Denizli, İzmir, Manisa, Muğla, Kütahya, and Uşak. The results revealed that Aegean Region has 528 million m3/year biogas potential corresponding to 2.64 TWh energy generation capacity. In addition, 0.6 million ton/year of organic fertilizer can be produced as the residual of the biogas plants. Utilization of animal wastes in biogas generation plants can contribute to the global climate change combat by reducing CO2 emissions about 4.6 million tons/year. Within the Aegean Region, Manisa has shown the highest biogas potential whereas İzmir has the highest amount of organic fertilizer production potential.

A comprehensive review on electricity generation and GHG emission reduction potentials through anaerobic digestion of agricultural and livestock/slaughterhouse wastes in Iran

Agricultural and livestock/slaughterhouse wastes are produced in huge quantities and could be promising sources for electricity generation to partially reduce dependence on fossil-oriented electricity. In light of that, the state of the production for these wastes in different parts of the globe was first presented. Subsequently, various waste-to-energy technologies and their electricity generation feasibility from both environmental and economic perspectives were reviewed. Finally, electricity generation and greenhouse gas (GHG) reduction potentials through anaerobic digestion of the above-mentioned wastes generated in each province of Iran in 2016 were investigated as a case study. Accordingly, Khuzestan province with the highest amount of agro-wastes (7.61 million tons) and Sistan and Baluchestan province with the highest amount of livestock/slaughterhouse wastes (10.69 million tons) had the maximum electricity generation potentials of 82.83 MW and 164.23 MW, respectively. Moreover, the country's total potentials for electricity generation from these wastes was determined at 2848.26 MW. Based on the life cycle assessment (LCA) results, a minimum of 10,693.5 thousand tons CO2eq/yr could be avoided by valorizing these wastes into electricity in Iran. This would be translated into 1.5% reduction of Iran's annual GHG emissions; a promising achievement given Iran's international GHGs reduction commitment. Moreover, if a short-term time horizon would be considered for electricity generation from these wastes, the reduction rate could reach 24,153 thousand tons CO2eq/yr, i.e., 3.39% reduction of Iran's annual GHG emissions. To the best of our knowledge, this is the first report scrutinizing electricity generation potentials from both agricultural and livestock/slaughterhouse wastes in Iran while assessing the consequent GHG emission reduction potentials. The outcomes of the study could assist policy makers with decisions aimed at taking advantage of these resources while the platform introduced pave the way for other researchers to conduct similar studies in different parts of the world.

Model-based analysis of greenhouse gas emission reduction potential through farm-scale digestion

An anaerobic digestion model was set up and applied to estimate desired methane production in the form of biogas as well as unwanted methane emissions associated with farm-scale digestion of manure. The generally accepted Anaerobic Digestion Model No. 1 was simplified assuming that hydrolysis is rate-limiting during anaerobic digestion of manure, mainly consisting of non-readily biodegradable compounds. Simulations were performed to demonstrate the effect of temperature and retention time on methane emissions resulting from long-term manure and digestate storage. Moreover, the overall carbon footprint of several manure management scenarios for Flemish dairy farms was assessed based on model simulations and literature data. The scenarios assessed, differed in the possible presence of a digester as well as in the manure collection and storage method. A reduction in methane emissions was achieved for lower manure storage temperatures (through external storage) and by decreasing the stored manure volume and thus the storage time before (controlled) anaerobic digestion. At the same time, feeding fresh manure induced an increased methane production in the digester. The lowest carbon footprint could be achieved on dairy farms with fresh manure collection by a manure scraper, followed by controlled digestion and storage of the digestate in a gas-tight tank, located outside. The controlled digestion must take place in a properly managed and correctly dimensioned reactor as high digester methane losses and low digester retention times increase the carbon footprint significantly.

Replacing short-haul flights with land-based transportation modes to reduce greenhouse gas emissions: The case of Finland

Even though air travel often provides the fastest transport option, it also has the highest climate impact. Especially on long-haul trips, an aircraft usually represents the only feasible option. Nevertheless, aircraft are more often used on short-haul routes as well. It is the short-haul flights that produce the highest emissions per passenger. These are also the ones that could be replaced the most easily by land-based transportation modes. This study investigates the greenhouse gas emissions reduction potential of replacing short-haul flights with train, coach and car travel within Finland while also taking into account real travel times from door to door. Our results showed that replacing short-haul flights could significantly reduce a country’s climate impact. Furthermore, we found that existing land-based transportation modes can keep up with the travel times of aircrafts on routes up to 400 km.

A hybrid scenario analysis for the selection of future greenhouse gas emissions reduction technologies in China’s oil and gas industry

Oil and gas provide approximately 22.7% of China’s total primary energy, but simultaneously absorbs 5% of that same energy. Increasing energy demands attributed to rapid industrialization stand in contradiction to China’s stringent policies to reduce greenhouse gas (GHG) emission. The GHG emissions of China’s oil and gas industry was 377 Mt CO2-eq in 2010, which was approximately 2.5 times higher than those of EU 27. Emission intensity in China is also much higher than that in EU 27. Accordingly, this study adopts a hybrid scenario analysis model to estimate the potential of GHG emission reduction of different technologies and policies in China’s oil and gas industry before 2030. The model was developed based upon a macroeconomic development model and a technology-based bottom-up system. The results indicate that GHG emissions will not peak before 2030 unless a strong reduction policy scenario (SP) is implemented. Technologies that can favor reduce GHG emissions were ranked through a cost-benefit analysis with results showing that, in the short term, integrated optimization of refining energy systems and torch optimizing with associated gas recovery should be promoted, while, after 2020, ‘advanced’ technologies including carbon dioxide (CO2) sequestration in saline aquifers and depleted hydrocarbon reservoirs, as well as CO2 enhanced oil recovery can further reduce GHG emissions. However, significant improvements in R&D is a prerequisite for cost-effectively implementing these technologies.

Life Cycle Assessment of a solar thermal system in Spain, eco-design alternatives and derived climate change scenarios at Spanish and Chinese National levels

Solar thermal energy is considered a ‘clean’ form of energy; however, environmental impacts occur during its life-cycle. The present work compares the environmental performance of two scenarios: a solar thermal system for providing domestic hot water (DHW) used in conjunction with a traditional natural gas heating system, and the natural gas heating system on its own. Weak points are found and different eco-design scenarios are evaluated in order to achieve a more circular economy. In addition, the authors explore what would be the national Greenhouse Gas emission reduction potential of a wider use of domestic solar hot water systems (DSHW) in China’s and Spain’s built environment. In this case, five displacement methods are suggested to show how the emissions reduction vary.Through a review of the state of the art and a Life Cycle Assessment of a solar system the two scenarios are assessed. Some impact categories, such as global warming, suggest a markedly better performance of the solar system (-65%). However, weak points in the solar solution have been identified as there is an increase of impacts in cases such as acidification (+6%) and eutrophication (+61%), mostly due to the metals used. The components with higher environmental impact are the collector, the tank, and the copper tubes.The reduction of national emissions by promoting DSHW depends on the actual displaced technology/ies. The consequences on national emissions reduction depending on these choices are assessed. The potential reduction of emissions, if 30% of the DHW were covered with solar sources, would be between 0.38% and 0.50% in the case of Spain and between 0.12% and 0.63% in China.

Testing the greenhouse gas emissions reduction potential of alternative strategies for the english housing stock

Buildings account for around a third of global energy and process emissions, but have been delivering much smaller emissions savings than other sectors. Although clear standards of new building construction and retrofitting options have been developed and are able to reduce building emissions, there is need for a clear prioritisation of policy options capable of delivering the greatest reduction in emissions at minimal costs. This requires an assessment of the trade-offs between new construction and retrofitting in terms of the pace of adoption of improved building standards and the emissions savings achieved to meet current climate targets. In this paper, a dynamic material flow analysis is used to explore the impact of combined mitigation strategies on both new and existing buildings capable of reducing embodied and operational emissions in the English domestic housing stock. The results show that progress in the use of low carbon materials in construction and the deployment of zero-carbon buildings at scale would not be enough to deliver a reduction of building emissions of the scale required nationally (–66% from current levels by 2050). Improvement in building standards for both new and pre-existing construction is essential to meet targets, but its costs are likely to be unreasonable without a reduction in the demand for floor area per capita by promoting flexible design of buildings, house sharing or telecommuting, which are likely to produce far-reaching implications in social organisation and urban planning.

Comparative Assessment of Climate Change Mitigation Policies in Fuel Combustion Sector of Lithuania and Bulgaria

The paper performed comparative assessment of greenhouse gas (GHG) emission trends and climate change mitigation policies in the fuel combustion sector of selected EU member states with similar economic development levels and historical pasts, and implementing main EU energy and climate change mitigation policies, having achieved different success in GHG emission reduction. The impact of climate change mitigation policies on GHG emission reduction was assessed based on analysis of countries’ reports to UNFCCC by identifying the key areas of GHG emission reduction, their GHG emission reduction potential, and the driving forces behind them. The study revealed that climate change mitigation policies that have been implemented so far in Bulgaria are less efficient than in Lithuania, as Bulgaria places priorities not on energy efficiency improvement and penetration of renewable energy sources, but on switching from coal to natural gas. The policy implications for strengthening GHG emissions reduction efforts are provided based on analysis conducted.

A Dynamic Fleet Model of U.S Light-Duty Vehicle Lightweighting and Associated Greenhouse Gas Emissions from 2016 to 2050.

Substituting conventional materials with lightweight materials is an effective way to reduce the life cycle greenhouse gas (GHG) emissions from light-duty vehicles. However, estimated GHG emission reductions of lightweighting depend on multiple factors including the vehicle powertrain technology and efficiency, lightweight material employed, and end-of-life material recovery. We developed a fleet-based life cycle model to estimate the GHG emission changes due to lightweighting the U.S. light-duty fleet from 2016 to 2050, using either high strength steel or aluminum as the lightweight material. Our model estimates that implementation of an aggressive lightweighting scenario using aluminum reduces 2016 through 2050 cumulative life cycle GHG emissions from the fleet by 2.9 Gt CO2 eq (5.6%), and annual emissions in 2050 by 11%. Lightweighting has the greatest GHG emission reduction potential when implemented in the near-term, with two times more reduction per kilometer traveled if implemented in 2016 rather than in 2030. Delaying implementation by 15 years sacrifices 72% (2.1 Gt CO2 eq) of the cumulative GHG emissionmitigation potential through 2050. Lightweighting is an effective solution that could provide important near-term GHG emission reductions especially during the next 10-20 years when the fleet is dominated by conventional powertrain vehicles.