47 research outputs found
Optimizing innovation, carbon and health in transport: assessing socially optimal electric mobility and vehicle-to-grid pathways in Denmark
This paper examines the social costs and benefits of potential configurations of electric vehicle deployment, including and excluding vehicle-to-grid. To fully explore the benefits and costs of different electric vehicle pathways, four different scenarios are devised with both today’s and 2030 electricity grid in Denmark. These scenarios combine different levels of electric vehicle implementation and communication ability, i.e. smart charging or full bi-directionality, and then paired with different levels of future renewable energy implementation. Then, the societal costs of all scenarios are calculated, including carbon and health externalities to find the least-cost mix of electric vehicles for society. The most cost-effective penetration of electric vehicles in the near future is found to be 27%, increasing to 75% by 2030. This would equate to a 1,200 in 2030. However, current vehicle capital cost differences, a lack of willingness to pay for electric vehicles, and consumer discount rates are substantial barriers to electric vehicle deployment in Denmark in the near term
Techno-Economic Aspects of Production, Storage and Distribution of Ammonia
The cost of green ammonia is determined primarily by its production cost, but it is also influenced by the cost of distribution and storage. Production costs are a function of plant location, size, and whether the plant is islanded or semi-islanded, that is whether the power source is variable renewable energy (VRE) or grid electricity. Capital costs for a green ammonia plant consist of equipment for the production of hydrogen (electrolyzer) and nitrogen (air separation), ammonia synthesis (Haber–Bosch, compressors and separators) and storage. Operating costs are mainly due to power consumption. The electrolyzer dominates both capital and operating costs in the manufacture of green ammonia. Ammonia is stored in either pressurized or refrigerated vessels with the latter preferred for large scale storage. Distribution of ammonia may involve several transport modes depending on the location of the production and consumption sites. Inland transport can involve pipelines, trains, and trucks, and offshore shipping is generally done with medium, large or very large gas carrier vessels with refrigerated tanks. A case study to supply a fleet of 36 ultralarge container vessels (ULCVs) operating between the ports of Shanghai and Rotterdam is used to exemplify the combination of production, storage and transportation costs
Asymmetrical LVRT of DFIG incorporating feed‐forward transient current control and controllable resistive‐type fault current limiter
Smart Grid Enabled Heat Pumps: An Empirical Platform for Investigating how Residential Heat Pumps can Support Large-scale Integration of Intermittent Renewables
On the use of the frequency domain in assessing resonant overvoltages during transformer energization.
• 2003 ELTRA – Design of Horns Rev Offshore WFAKS
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Hardware‐in‐the‐loop tests on distance protection considering VSC fault‐ride‐through control strategies
Incentivising flexible power-to-heat operation in district heating by redesigning electricity grid tariffs
Energy balances for biogas and solid biofuel production from industrial hemp
If energy crops are to replace fossil fuels as source for heat, power or vehicle fuel, their whole production chain must have higher energy output than input. Industrial hemp has high biomass and energy yields. The study evaluated and compared net energy yields (NEY) and energy output-to-input ratios (RO/I) for production of heat, power and vehicle fuel from industrial hemp. Four scenarios for hemp biomass were compared; (I) combined heat and power (CHP) from spring-harvested baled hemp, (II) heat from spring-harvested briquetted hemp, and (III) CHP and (IV) vehicle fuel from autumn-harvested chopped and ensiled hemp processed to biogas in an anaerobic digestion process. The results were compared with those of other energy crops. Calculations were based on conditions in the agricultural area along the Swedish west and south coast. There was little difference in total energy input up to storage, but large differences in the individual steps involved. Further processing to final energy product differed greatly. Total energy ratio was best for combustion scenarios (I) and (II) (RO/Iof 6.8 and 5.1, respectively). The biogas scenarios (III) and (IV) both had low RO/I(2.7 and 2.6, repectively). They suffer from higher energy inputs and lower conversion efficiencies but give high quality products, i.e. electricity and vehicle fuel. The main competitors for hemp are maize and sugar beets for biogas production and the perennial crops willow, reed canary grass and miscanthus for solid biofuel production. Hemp is an above-average energy crop with a large potential for yield improvements