Electrofuels from excess renewable electricity at high variable renewable shares: cost, greenhouse gas abatement, carbon use and competition

Increasing shares of variable renewable electricity (VRE) generation are necessary for achieving high renewable shares in all energy sectors. This results in increased excess renewable electricity (ERE) at times when supply exceeds demand. ERE can be utilized as a low-emission energy source for sectorcouplingthroughhydrogenproductionviaelectrolysis, whichcanbeuseddirectlyorcombined with a carbon source to produce electrofuels. Such fuels are crucial for the transport sector, where renewable alternatives are scarce. However, while ERE increases with raising VRE shares, carbon emissions decrease and may become a limited resource with several usage options, including carbon storage (CCS). These counteracting eﬀects for the electrofuel production have not been analysed before. Here we perform a model based analysis for the German case until 2050, with a general analysis for regions with a high VRE reliance. Results indicate that ERE-based electrofuels can achieveagreenhousegas(GHG)abatementof74MtCO2eqyearly(46%ofcurrentGermantransport emissions) by displacing fossil fuels, at high fuel-cell electric vehicle (FCEV) shares, at a cost of 250320 € t CO2eq−1. The capital expenditure of electrolysers was found not to be crucial for the cost, despitelowcapacityfactorsduetovariableEREpatterns. Carbonwilllikelybecomealimitingfactor when aiming for stringent climate targets and renewable electricity-based hydrocarbon electrofuels replacing fossil fuels achieve up to 70% more GHG abatement than CCS. Given (1) an unsaturated demandforrenewablehydrocarbonfuels,(2)asaturatedrenewablehydrogendemandand(3)unused ERE capacities which would otherwise be curtailed, we ﬁnd that carbon is better used for renewable fuel production than being stored.<br>

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Electrofuels from Excess Renewable Electricity at High Variable Renewable Shares: Cost, Greenhouse Gas Abatement, Carbon Use and Competition

10.26434/chemrxiv.12287504 ◽

2020 ◽

Author(s):

Markus Millinger ◽

Philip Tafarte ◽

Matthias Jordan ◽

Alena Hahn ◽

Kathleen Meisel ◽

...

Keyword(s):

Fossil Fuels ◽

Capital Expenditure ◽

Limited Resource ◽

Transport Sector ◽

Renewable Electricity ◽

Fuel Production ◽

Climate Targets ◽

Low Emission ◽

Greenhouse Gas Abatement ◽

The Cost

Increasing shares of variable renewable electricity (VRE) generation are necessary for achieving high renewable shares in all energy sectors. This results in increased excess renewable electricity (ERE) at times when supply exceeds demand. ERE can be utilized as a low-emission energy source for sectorcouplingthroughhydrogenproductionviaelectrolysis, whichcanbeuseddirectlyorcombined with a carbon source to produce electrofuels. Such fuels are crucial for the transport sector, where renewable alternatives are scarce. However, while ERE increases with raising VRE shares, carbon emissions decrease and may become a limited resource with several usage options, including carbon storage (CCS). These counteracting eﬀects for the electrofuel production have not been analysed before. Here we perform a model based analysis for the German case until 2050, with a general analysis for regions with a high VRE reliance. Results indicate that ERE-based electrofuels can achieveagreenhousegas(GHG)abatementof74MtCO2eqyearly(46%ofcurrentGermantransport emissions) by displacing fossil fuels, at high fuel-cell electric vehicle (FCEV) shares, at a cost of 250320 € t CO2eq−1. The capital expenditure of electrolysers was found not to be crucial for the cost, despitelowcapacityfactorsduetovariableEREpatterns. Carbonwilllikelybecomealimitingfactor when aiming for stringent climate targets and renewable electricity-based hydrocarbon electrofuels replacing fossil fuels achieve up to 70% more GHG abatement than CCS. Given (1) an unsaturated demandforrenewablehydrocarbonfuels,(2)asaturatedrenewablehydrogendemandand(3)unused ERE capacities which would otherwise be curtailed, we ﬁnd that carbon is better used for renewable fuel production than being stored.<br>

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A model-based approach to measuring denitrification and greenhouse gas production in lakes

10.32920/ryerson.14655129 ◽

2021 ◽

Author(s):

Juliet Falco Ajambo-Doherty

Keyword(s):

Greenhouse Gas ◽

Atmospheric Pressure ◽

Schmidt Number ◽

Spatial Scales ◽

Gas Production ◽

System Model ◽

Biogeochemical Processes ◽

Model Based ◽

Temporal And Spatial ◽

System Metabolism

An existing whole-system model based on changes in dissolved N₂ concentration was modified for lentic systems. Field validations carried out at Christie Lake in Dundas, ON and Turtle Pond in Stoney Creek, ON (Canada). New model inputs included air temperature, atmospheric pressure, relative humidity, wind velocity, and Schmidt number. Mont Carlo analysis was integrated into the model to better constrain error in model estimates of denitrification, whole-system metabolism, and greenhouse gas production. Denitrification rates ranged from -419-4415 µmol N.m-².h-¹ in Christie Lake and from 10-74 µmol N.m-².h-¹ in Turtle Pond. N₂O production ranged from 915-10,635 nmol N.m-².h-¹ in Christie Lake and from -344-131 nmol N.m-².h-¹ in Turtle Pond. The whole-system model allows for the examination of biogeochemical processes at ecologically significant temporal and spatial scales.

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Methodological contrasts in costing greenhouse gas abatement policies: Optimization and simulation modeling of micro-economic effects in Canada

European Journal of Operational Research ◽

10.1016/s0377-2217(01)00402-7 ◽

2003 ◽

Vol 145 (1) ◽

pp. 148-164 ◽

Cited By ~ 21

Author(s):

Mark Jaccard ◽

Richard Loulou ◽

Amit Kanudia ◽

John Nyboer ◽

Alison Bailie ◽

...

Keyword(s):

Greenhouse Gas ◽

Simulation Modeling ◽

Economic Effects ◽

Abatement Policies ◽

Optimization And Simulation ◽

Greenhouse Gas Abatement

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Estimating the supply of oilseed acreage for sustainable aviation fuel production: taking account of farmers’ willingness to adopt

Energy Sustainability and Society ◽

10.1186/s13705-021-00308-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Conner J. McCollum ◽

Steven M. Ramsey ◽

Jason S. Bergtold ◽

Graciela Andrango

Keyword(s):

Greenhouse Gas Emissions ◽

Greenhouse Gas ◽

Pacific Northwest ◽

Great Plains ◽

Secondary Data ◽

Aviation Fuel ◽

Fuel Production ◽

Gas Emissions ◽

Willingness To Adopt ◽

Reduce Emissions

Abstract Background Continued progress towards reducing greenhouse gas emissions will require efforts across many industries. Though aviation is estimated to account for modest portions of global greenhouse gas emissions, these shares may grow as the industry expands. The use of biomass- and crop-based sustainable aviation fuels can help reduce emissions in the industry. However, limited feedstock supplies are a barrier to increased use of these fuels. This study examines the potential supply of feedstock from oilseeds and farmer willingness to produce oilseed crops under contract for sustainable aviation fuel production with a focus on canola and similar oilseed feedstocks (e.g., rapeseed). Stated-choice survey data is used to examine the contract and crop features that drive contract acceptance in six states located in the U.S. Great Plains and Pacific Northwest and then acreage supply curves are estimated for canola using secondary data. Main findings The estimated number of acres supplied under contract varies considerably across states and scenarios. Relatedly, estimated supply curves exhibit high degrees of price responsiveness. Of the states analyzed, oilseed acreages supplied under contract are generally found to be greatest in Kansas and North Dakota. Conclusions Results suggest that in the absence of favorable contract and crop scenarios canola and other oilseed prices will need to considerably increase from typical levels to induce higher levels of supplied acres. The presence of crop insurance, shorter contract lengths that provide cost sharing and the availability of particular crop attributes are shown to diminish the need for higher canola and other oilseed prices.

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