Electricity Generation Scenarios Research Articles

Long-term electricity generation analysis and policy implications – the case of Ghana

The pursuit of a cost-effective and low-carbon electricity generation environment is critical to achieving Ghana's economic and industrial ambitions. Ghana’s development agenda calls for an average electricity consumption of about 5,000 kWh per capita by 2030. To this end, the effective harnessing of energy resources requires the implementation of robust policies for sustainable electricity generation. This study employs the IAEA MESSAGE analytical tool to conduct a quantitative assessment of electricity generation in Ghana from 2020 to 2048. The findings show that, by 2048, a diversified electricity generation scenario will result in a 32.30% decrease in cost and a 55.27% reduction in CO2 emissions, compared to an accelerated economic growth (AEG) scenario, which will increase cost and CO2 emissions by 12.21% and 21.10%, respectively. The results underscore the importance of ensuring that electricity generation policies balance economic, environmental, and social concerns. Achieving a green energy transition agenda in Ghana and other developing nations will require a long-term commitment to a generation mix that is both sustainable and economically viable. The implementation of such a policy will require an informed and dedicated effort from all stakeholders.

Internal spillover effect of carbon emission between transportation sectors and electricity generation sectors

The exact carbon reduction potential of transportation electrification has not been answered directly from the coupled view of electric power transmission and transportation. To address this issue, the multi-regional input-output model and quasi-input–output model are used. Through simulation results comparison between the baseline scenario and transportation electrification scenario, we can observe that transportation electrification scenario would finally reduce 403 million tons, while the increase of 302 million tons of CO2 from the electricity generation sector due to the spatial spillover effect offsets the reduced 705 million-tons decarbonization benefits of the traffic transportation sector, as well as the decarbonization benefits of cleaner electricity generation. The total reduced CO2 emissions under the combined scenario are 1997 million tons, which is 94 million tons larger than the overall effect of the separate implementation of transportation electrification scenario and cleaner electricity generation scenario. We conclude that to reduce carbon emission transfer, much greater attention needs to be paid to cleaner generation mix construction.

Driving the clean energy transition in Cameroon: A sustainable pathway to meet the Paris climate accord and the power supply/demand gap

The Intergovernmental Panel on Climate Change (IPCC) 2021 report has noted the perceived rise in severe weather phenomena such as heat radiations, hurricanes, flooding, and droughts and the rising scientific evidence attributing these events to anthropogenic sources of climate change. Cameroon as a nation is equally exposed to these climate vulnerabilities, and contributing to global climate efforts is imperative. She has earmarked the integration of 25% renewables in its electricity production mix and a 32% emission reduction, all as part of her commitment to global climate action. The fresh commitments coupled with a rapidly growing power demand have paved the way for a revolutionized approach to electricity generation in Cameroon. However, the imminent changes, as well as their implications, remain uncertain. This study explores how these emission reduction targets can be achieved through the adoption of a more sustainable power transition, which provides realistic solutions for emission reduction, escaping high carbon pathways. The assessment of the level at which long-term electricity generation scenarios in Cameroon could be renewable energy intensive was done using the Low Emissions Analysis Platform (LEAP) tool following a backcasting approach. The study noted that there is an implementation gap between earmarked policy ambitions and existing measures. The study recommended several opportunities in aspects, such as suitable share of technologies, administrative reforms, and required adjustments within the Nationally Determined Contributions (NDCs), which the government could exploit in the electricity sector to sail across the challenging trade-offs needed to become a sustainable economy in a carbon-constrained world. It equally examines actions that could help close the gap between earmarked policy ambitions and existing pathways and proposes cost-effective methods that were identified as priorities.

Mixtures of heavy fuel oil and green hydrogen in combustion equipment: Energy analysis, emission estimates, and economic prospects

The high environmental impact of fossil fuels combined with the rise of carbon dioxide in the atmosphere has made the search for renewable fuels imperative. The study assesses the technical and economic viability of replacing heavy fuel oil (HFO) with green hydrogen (H2) in industrial plants for high temperature generation (>1100 K). The study also estimates the emissions generated by the plants after the fuel switch in terms of particulate matter (PM), SO2, NOx and CO2 emissions. To illustrate the feasibility of this replacement, an assessment of a calcination furnace at a pulp plant in Chile in 2022 was carried out, taking into account two electricity generation scenarios for H2 production by water electrolysis. Replacing HFO with a mixture of H2 + HFO was beneficial in terms of emissions. The financial assessment showed that blending H2 with HFO of up to 20 % is the best solution, considering current fuel prices, and that full substitution of HFO with H2 after 2030 is economically viable.

Air/Water Heat Pumps in Existing Heating and Hot Water Systems for Better Urban Air Quality and Primary Energy Savings: Scenarios of Two Italian Cities

In a previous work, a significant contribution to urban air pollution, related to fuel-fired heating systems, was recorded. Thus, the replacement of existing boilers for space heating and domestic hot water (DHW) production systems with high-temperature air/water heat pumps (which can operate with radiators, the most common terminals in the existing building stock), is proposed for the improvement of the urban air quality. Scenarios of substitution within the entire residential building stock of two Italian cities, Milan and Salerno, belonging to different climate zones and with their own thermophysical characteristics, were analyzed. For each of them, the consequences of the replacement intervention on emission reduction, primary energy savings and lower CO2 production were evaluated. The results show that reduction of primary energy consumption, evaluated at design outdoor temperature and for the present generation mix, varied between 34% and 54% in Milan and between 43% and 60% in Salerno, for two values of renewable fraction in electricity generation. The reduction of CO2 production was in the range 30–52% in Milan and 39–58% in Salerno, respectively. The only unfavorable case occurred for Milan for a completely non-renewable electricity generation scenario. The replacement intervention, which implies a significant decrease of emissions of pollutants in urban areas, is unobtrusive to citizens, since the heat pumps (HPs) are coupled with current radiators, without the internal distribution system being modified.

Does green vertical farming offer a sustainable alternative to conventional methods of production?: A case study from Scotland

AbstractClimate change is an existential global reality that is placing considerable stress on agriculture sectors. With the recognition of the impacts of climate change on food security, there has been a greater uptake of controlled environment agriculture (CEA) to provide climate‐resilient and high‐quality production. Vertical farming (VF) can allow primary production in urban locations as well as reducing seasonality and variability in produce. It is emerging as an alternative to traditional farming methods. This research aimed to explore the major environmental impacts of VF produce in comparison with conventional farming methods, using lettuce as an example crop. Life cycle analysis indicate that electricity consumption by VF account for 91% of the carbon footprint. Under the 2019 Scottish electricity mix, VF did not offer a viable competitor for UK open‐farmed lettuce or Spanish imports in terms of low greenhouse gas emissions (at approximately 1.49 kgCO2 eq. kg−1). However, with increasing use of renewable electricity in the national mix, by 2020, this had dropped to 0.42 kgCO2 eq. kg−1 making it comparable with UK open‐field agriculture (at approximately 0.46 kgCO2 eq. kg−1). Under a 100% renewable electricity generation scenario, VF‐related emissions drop further (to 0.33 kgCO2 eq. kg−1). This would potentially offer a low‐carbon production method not subject to seasonality which is better than that reported by most other production methods and offers higher water and nutrient efficiency. This research highlights green VF as potential alternative for sustainable future produce especially under changing climate scenarios.

An energy-mix model for round-the-clock power supply in a decarbonized electricity generation scenario: case study of South India

There is increasing urgency towards integration of renewable sources into electricity generation so as to minimize greenhouse gas (GHG) emissions. Renewable power sources are highly specific in prevalence, both regionally and temporally, and their utilization at utility scale for round-the-clock power supply poses the problem of matching power generation capacity and power demand at every instant of time. In the present work, we propose a model that integrates geographically distributed and diverse power sources with geographically spread-out power consumption centres and distributed and diverse electrical energy storage systems through transmission and storage loss models. For a regional electricity grid, the model computes, over a given day, the minute-by-minute power demand from and power generation in all districts, extracts matching power from a hierarchy of power sources so as to minimize transmission and storage losses, and stores/draws excess power in/from a variety of power storage options. For the specific case of the South Indian Power Grid (catering to about 285 million people in South India), the model shows that about 240 GWh of new electrical storage is required for round-the-clock power supply from non-GHG power sources.Graphical abstract

Sustainability prioritization of energy systems under hybrid information and missing information based on the improved grey relational analysis

Life cycle sustainability of energy systems has received more and more attentions recently. In order to make an accurate comparison of the sustainability performance of different energy systems and promote the decision-making process, various prioritization methods of energy systems were developed. However, the lack of enough data for decision-making usually limits the accuracy of the prioritization. On the one hand, the decision-makers can only collect multiple types of data resources with hybrid information, for example, data in the formats of crisp numbers, interval numbers, and fuzzy numbers. On the other hand, some information for certain alternatives with respect to certain criteria is hard to be obtained. Therefore, it is of vital importance to achieve sustainability-oriented prioritization of energy systems under hybrid information and missing information. This study aims at developing a prioritization framework for energy systems ranking with missing information and hybrid information. An improved Grey Relational Analysis (GRA) is extended from the classical GRA method to handle hybrid information in this study. An innovative method to quantify linguistic expressions is proposed to deal with missing information. A hypothetical case study regarding electricity generation scenarios selection was used to evaluate the feasibility of this proposed framework. Sensitivity analysis was also conducted, and the results showed that the iGRA-MH is feasible in handling hybrid and missing information and it performs more stable than other multi-criteria decision-making models.

Global Biodiversity Implications of Alternative Electrification Strategies Under the Shared Socioeconomic Pathways

Addressing climate mitigation while meeting global electrification goals will require major transitions from fossil-fuel dependence to large-scale renewable energy deployment. However, renewables require significant land assets per unit energy and could come at high cost to ecosystems, creating potential conflicts between global climate mitigation and biodiversity conservation. Here, we explore the potential biodiversity implications of alternative future global electrification pathways as depicted under the Shared Socioeconomic Scenarios (SSPs), i.e., alternative trends in societal development. We examined the intersection of high-resolution estimates of global energy densities for ten renewable and conventional technologies with global richness data to estimate technology-specific biodiversity footprints (species per GWh), whereas a Cumulative Biodiversity Impact (CBI) score was used to assess land and biodiversity outcomes of alternative scenarios. Downscaled electricity generation scenarios (2020−2100) were also constrained by alternative land conservation and energy development policies. Unexpectedly, variation among SSPs did not exhibit a clear tradeoff between global climate mitigation and CBI. Rather, CBIs were an outcome of total infrastructure development to meet electricity demand (from population growth and GDP) and the total magnitude of renewable energy development and storage technologies. Renewables assembled along a spectrum from land sharing to sparing. At the land sharing end, biomass-powered electricity from dedicated crops contributed the most to biodiversity impacts due to low energy density, whereas land-sparing technologies (solar) caused more-intense land degradation, but in smaller areas. Our results suggest that local land conservation practices and strategies promoting energy diversification could have greater implications for future biodiversity conflicts than global socioeconomic drivers.

A new methodology to estimate future water‐energy nexus based on artificial neural networks

We propose a new methodology to evaluate future electricity generation scenarios aiming to explore implications of different sets of power plants on the water-energy nexus (W-EN). We use two artificial neural networks: cascade forward back propagation and Kohonen neural networks (KNN). Initially, the future electricity production of the area under investigation is determined. Sequentially, water consumption is calculated for different combinations of plants. The scenarios with the lowest annual water consumption values are based only on wind and photovoltaic (PV) plants. Despite using only renewable energy, the inclusion of concentrating solar power in a future scenario brings a significant increase in water consumption, challenging the sustainability of this matrix. A conservative scenario (50% of electricity production by thermal power plants and 50% by renewable energy) shows the highest annual water consumption, also a barrier to sustainability.

Low emission vehicle integration: Will National Grid electricity generation mix meet UK net zero?

Assessing greenhouse gas (GHG) emissions produced from electric vehicles (EVs) and hydrogen vehicles (HVs) requires understanding of the carbon intensity of electricity generation. Without the decarbonisation of electricity generation, environmental benefits of low emission vehicles (LEVs) will be diminished. The UK aims to produce net zero emissions by phasing out and banning the sale of new conventionally fuelled vehicles (CFVs) by 2035 in favour of LEVs. A comparison of the UK’s planned and future electricity production systems between 2020 and 2050 was conducted to analyse different vehicle-type mix scenarios: (1) 100% CFVs, (2 A/B) 100% EVs/HVs, (3 A/B) EVs/HVs integrated from 2035 and (4 A/B) EVs/HVs integrated from 2025 onward. This was conducted using four energy scenarios from the UK National Grid: two degrees, steady progression, consumer evolution and community renewables. This study does not consider the embedded carbon costs of the construction and decommissioning of vehicles. Results demonstrated that while the four electricity generation scenarios reduce the projected emissions they fail to achieve low emission targets. The two degree scenario produced the lowest level of emissions under each vehicle-type mix scenario. Technological improvements of CFVs are not enough to meet targets. Therefore, phasing out and banning the sale of new CFVs from 2025 (rather than 2035) would provide a stronger impetus to reduce transport emissions. Although these targets are possible, encouraging a change in transport modes from individual travel to public transport whilst simultaneously replacing buses and trains with electric or hydrogen alternatives would see a greater emission decrease.

Renewable energy scenarios for sustainable electricity supply in Nigeria

An attempt has been made using a bottom-up model to examine business-as-usual and 100% renewable electricity generation scenarios for Nigeria. Results indicate that Nigeria can achieve 100% renewable electricity supply by 2050 with the deployment of a mix of renewable energy technologies, especially utility-scale solar PV and onshore wind turbines. CO2 emissions are expected to peak by 2030 and decline to zero in 2050. In terms of total system cost, a transition to 100% renewable electricity by 2050 is a cheaper option compared to the conventional pathway, and it could potentially create around 1.54 million jobs for Nigerians by 2050.

Environmental assessment of 2030 electricity generation scenarios in Sicily: An integrated approach

Abstract This paper deals with the environmental assessment of two electricity scenarios in Sicily, for 2030, characterized by a high exploitation of renewable energy sources in order to quantify the potential contribution of the local strategies in the achievement of the European climate policies and the potential improvement in the future electricity mix, compared to the current one (2014). In order to match these goals, authors integrate the Life Cycle Assessment with a scenario analysis. The future electricity mix scenarios, characterized by a share of renewables (57% for 2030-BS scenario and 51% for 2030-DS scenario) show a reduction of the greenhouse gases emissions per kWh of electricity generated, compared to the current one in which renewables account for 24%. Greenhouse gases emissions decrease by 39.9% in 2030-BS and by 32.9% in 2030-DS. However, the analysis highlights that the state of development of technologies does not allow improvements in a whole set of impacts categories. Particularly, freshwater ecotoxicity increases by around 30% and resources depletion by more than 100%. Results of this study can be used by local authorities as knowledge base in the definition and ex-ante evaluation of site-specific low-carbon energy strategies in Sicily.

Assessment of Electricity Decarbonization Scenarios for New Zealand and Great Britain using a Plant Dispatch and Electrical Energy Storage Modelling Framework

This paper proposes a methodology to assess the impact of alternative electricity generation and energy storage scenarios for meeting electricity demand on a national level. The method combines real and synthetic electricity generation and demand data to investigate different decarbonization strategies using solar and wind generation and electrical energy storage. This method is applied to provide relevant case studies for two geographically similar electricity systems in New Zealand and Great Britain. Newly available solar and wind data sets at hourly resolution are used within this method for these systems to assess the potential contribution of these technologies and as such, to refresh understanding of the impact of these technologies on decarbonization strategies against historical and future demand patterns. Although wind, solar and storage technologies are found to reduce the carbon emissions in both electricity systems, a key result is quantifying the impact this has on traditional generation as a backup resource. In New Zealand an investment in wind and solar equivalent to less than 15% of the wind/solar capacity in Great Britain is found to (i) reduce fossil fuel use to less than 2% of annual electricity generation requirements in the data assessed and (ii) remove the need for continuous operation of fossil fuel plants. Further, it is shown that existing hydro storage potential could be used to create near complete decarbonization of New Zealand electricity

Optimization of Lebanon's power generation scenarios to meet the electricity demand by 2030

Presently, Lebanon provides 95 % of the primary energy electricity power generation by using fuel-oil used in thermal power plants. To meet the population needs, private generators are also used in all the country and they represent the third of total electricity production. The challenges over the future development of the Lebanese electric sector are economic and environmental. This is why currently, the energy policy makers aim to diversify the national electricity generation mix in the energy planning strategy and to introduce low-carbon technologies. The complexity of these challenges in the particular Lebanese context has motivated our study which aims to recommend policies to develop the optimal electricity generation scenario by 2030. This paper presents a methodology to evaluate different scenarios reflecting different combinations of technologies by 2030. This is achieved by using an excel tool “Excel Solver Optimization Calculator” which makes possible the interaction of various inputs to produce a least-cost generation mix. The main results focus on the least-cost electricity generation portfolio, total investment required to generate electricity, level of energy independence and carbon emissions. Many policy choices could be feasible and very advantageous for Lebanon if renewable energies are deployed massively. However, this requires policies that support the massive use of renewable energy technologies in the mix.

Differences in CO2 emissions of solar PV production among technologies and regions: Application to China, EU and USA

A widespread implicit assumption is that renewable energy options are approximately low-carbon. However, production and life cycles of such technologies tend to produce CO2 emissions. To minimize life-cycle emissions, one should account for such emissions and implement adequate policies to encourage innovation and adoption of well-performing technologies in this respect. We develop a framework to analyse this issue, grounded in the concepts of ‘energy return on energy invested’ (EROI) and ‘net energy return on carbon invested’ (EROC). Applying these to the main PV technologies and production regions – namely China, EU and USA – displays considerable discrepancies. We conditionally predict the development of average EROI and EROC over time under business-as-usual and low-carbon electricity generation scenarios. A main policy lesson is that without a systemic policy instrument, such as carbon pricing, incentives for low-carbon production of renewable energy options are too weak, which likely will delay a complete transition to a low-carbon economy.

Techno-econo-environmental optimal operation of grid-wind-solar electricity generation with hydrogen storage system for domestic scale, case study in Chad

The rapidly growing of population in the developing countries and their lack of access to electricity, especially in the remote or rural areas, is causing huge challenges for on energy production. Energy is an enabler and a reliable energy supply is critical to sustainable socio-economic development for any nation. Most of Chad's people live in villages with no particular power supply system. Exploiting renewable energies is the only means of fostering development and improving people's welfare. This paper attempts at proposing an energy profile and storage model for Chad in vast remote towns. The paper addresses the key energy gap that is hindering on the development of such systems, it models and assess the potential on electricity generation and using hydrogen as surplus power storage system. A techno-econo-environmental survey on a solar-wind hybrid system in 25 towns in Chad is undertaken using NASA data and HOMER Software. Several hybrid scenarios of energy production and storage is analyzed. The results showed that in the electricity generation scenario, the average total NPC for the studied stations was $ 48164 and the average LCOE was $0.573. The lowest LCOE was related to Aouzou station with 0.507 $/kWh and the highest LCOE was obtained for Bol station with 0.604 $/kWh. In the simultaneous electricity and hydrogen generation scenario, the cheapest hydrogen ($4.695/kg) was produced in the “Grid” scenario, which was the same for all of the stations, with a total NPC of $2413770. The most expensive hydrogen ($4.707/kg) was generated in the “Grid-Wind” scenario and Bol stations with a total NPC of $2420186. The paper develops cost effective models for all hybrid systems combination for both electricity and hydrogen generation across Chad. These findings could help policy makers, investors and other developmental agencies make informed choices on energy access for sustainable development for rural communities in Sub Saharan Africa.

Environmental feasibility of incorporation of electric taxis in South Africa

Public transport is very influential industry affecting our society due to its significant environmental and social impact. Policy makers have seen electric vehicle as a tool to reduce greenhouse gas emissions. Cleanliness of power from the electricity grid plays a vital role in environmental impact in the transition to electric vehicle. In countries like China, USA, India etc., majority of electricity generation is still dominated by fossil fuel fired generators. Thus, in some cases, the environmental impact of electric vehicle may be more adverse in comparison to conventional internal combustion engine vehicles (ICEV). This paper tries to study the environmental effect of incorporation of 100 Electric Vehicle taxies in Johannesburg (JNB), South Africa. Firstly, the current electricity generation scenario and vehicles standards of SA with its carbon emission is discussed. Secondly, it is shown that with the current generation mix the adoption of EV is not sustainable. Finally, penetration of Renewable Energy (RE) system at charging stations is proposed with Renewable Energy Fraction (REF) of 40% and 58% to make carbon mission from EV equivalent to Euro III and Euro V standards of petrol ICEV. The optimised size of RE system is found using the Electric System Cascade Analysis.

Life-cycle impact and exergy based resource use assessment of torrefied and non-torrefied briquette use for heat and electricity generation

Forest residue biomass can be used as bioenergy feedstock, however, issues associated with its properties including low density and high moisture content constrains its valorization. Using mobile conversion technologies that can operate in remote areas and are capable of converting forest residues into high quality energy products can address the issues associated with its valorization for renewable energy production. This study evaluated environmental sustainability of using an integrated novel system of semi-mobile biomass conversion technologies (BCTs) to utilize low-value forest residue biomass as high value bioenergy products. A cradle-to-grave life cycle assessment (LCA) and resource use assessment on a unit-process level was conducted for two bio-products: nontorrefied briquettes (NTB) and torrefied briquettes (TOB). Their use for production of useful thermal energy in wood stoves for domestic heating and electricity at power plants were investigated along with their alternatives. The analyses were performed with SimaPro 8.5 using the DATASMART database. The impact assessment results showed a notable decrease in global warming (GW) impact when substituting fossil fuels with these two bio-products. Specifically, for domestic heating on an equivalent energy basis, a 50% substitution of propane with NTB and TOB showed GHG emission reductions of 46% and 41%, respectively. For electricity generation, 10% cofiring at coal power plant with NTB and TOB showed GHG emission reductions of 6% and 8%, respectively. For the TOB supply chain, a large portion of the GW impact of the came from the torrefaction process and followed by the drying process. This was due to the propane use in these processes. Comparative analysis showed that near-woods biomass conversion for TOB production instead of processing feedstock at an in-town facility with access to grid electricity found 48%–55% lower GW impact for both electricity and heat generation scenarios, respectively. Resourced footprint analysis showed that most exergy extraction from the natural environment came from the drying process for NTB supply chain. In the TOB product system, torrefaction was the major contributor.

Greenhouse Gas Emission of Electricity Generation and Field Abandonment Scenarios Using Empty Fruit Bunches at a Palm Oil Mill, Surat Thani Province, Thailand

In Indonesia, Malaysia, and Thailand, the pile abandonment of empty fruit bunches (EFBs) in the fields of palm oil mills is a common practice. This practice results in environmental issues such as generation of unpleasant odors and methane production due to anaerobic decomposition. In the present study, an abandoned moist EFB sample from Rubber Oil Co. Limited, a palm oil mill in the Thachi sub-district municipality, Surat Thani Province, southern Thailand, was collected and sun dried for physical analysis. The bulk density at 13.2% moisture content was 0.118 kg/L. Greenhouse gas (GHG) emissions for electricity generation and methane production due to anaerobic decomposition were compared applying life cycle assessment. A cargo capacity of 621 kg of EFBs and a 59 km distance to the Surat Thani Biomass Power Plant in Surat Thani province were adapted with reference to Thailand’s GHG emission factors. The system boundary included the EFBs in the palm oil mill and the nearest power plant. The CO2 equivalent GHG emissions per kg of EFB for the transportation, generation, and field abandonment (methane emission) were 0.077, -0.877, and 2.136 kg-CO2e, respectively; a sum of -0.8 kg-CO2e emission via electricity generation use was noted as a significant environmental advantage.