Nina Juul - Academia.edu (original) (raw)

Papers by Nina Juul

ABSTRACT Assessing grid developments the spatial distribution of the electricity consumption is i... more ABSTRACT Assessing grid developments the spatial distribution of the electricity consumption is important. In Denmark the electricity grid consists of transmission - and local distribution grids with different voltages that are connected via transformer stations each covering a local area with between 10.000 and 100.000 customers. Data for the hourly electricity consumption at transformer stations shows that the profile of consumption differs considerably between local areas, and this is partly due to a different weight of categories of customers in the different areas. Categories of customers have quite distinct consumption profiles and contribute quite differently to the aggregated load profile. In forecasts, demand by categories of customers is expected to develop differently implying that both the level and the profile of consumption at each transformer stations are expected to change differently. Still, in the previous planning of the transmission grid in Denmark specific local conditions have not been considered.

European Journal of Operational Research, 2014

ABSTRACT For electricity market participants trading in sequential markets with differences in pr... more ABSTRACT For electricity market participants trading in sequential markets with differences in price levels and risk exposure, it is relevant to analyze the potential of coordinated bidding. We consider a Nordic power producer who engages in the day-ahead spot market and the hour-ahead balancing market. In both markets, clearing prices and dispatched volumes are unknown at the time of bidding. However, in the balancing market, the market participant faces an additional risk of not being dispatched. Taking into account the sequential clearing of these markets and the gradual realization of market prices, we formulate the bidding problem as a multi-stage stochastic program. We investigate whether higher risk exposure may cause hesitation to bid into the balancing market. Furthermore, we quantify the gain from coordinated bidding, and by deriving bounds on this gain, assess the performance of alternative bidding strategies used in practice.

Energy, 2011

Integrating the power and transport system, in the future energy system planning, influences the ... more Integrating the power and transport system, in the future energy system planning, influences the economically optimal investments and optimal operation of the power system as well as the transport system. For analysing the integrated power and transport system a new model capable of calculating optimal investments in both power plants and vehicle technologies is presented in this article. The model includes the interactions between the power system and the transport system including the competition between flexibility measures such as hydrogen storage in combination with electrolysis, heat storage in combination with heat pumps and heat boilers, and plug-in electric vehicles.

Energy, 2012

ABSTRACT In this study, it is analysed how a large-scale implementation of plug-in hybrid electri... more ABSTRACT In this study, it is analysed how a large-scale implementation of plug-in hybrid electric vehicles and battery electric vehicles towards 2030 would influence the power systems of five Northern European countries, Denmark, Finland, Germany, Norway, and Sweden. Increasing shares of electric vehicles (EVs) are assumed; comprising 2.5%, 15%, 34%, and 53% of the private passenger vehicle fleet in 2015, 2020, 2025, and 2030, respectively. Results show that when charged/discharged intelligently, EVs can facilitate significantly increased wind power investments already at low vehicle fleet shares. Moreover, due to vehicle-to-grid capability, EVs can reduce the need for new coal/natural gas power capacities. Wind power can be expected to provide a large share of the electricity for EVs in several of the countries. However, if EVs are not followed up by economic support for renewable energy technologies, coal based power will in several cases, particularly in the short term, likely provide a large part of this electricity. The effects of EVs vary significantly from country to country and are sensitive to fuel and CO2 price variations. The EVs bring CO2 reductions of 1–6% in 2025 and 3–28% in 2030 while total costs are generally increased.

Applied Energy, 2012

Increasing focus on sustainability affects all parts of the energy system. The future integration... more Increasing focus on sustainability affects all parts of the energy system. The future integration of the power and road transport system due to the introduction of electric drive vehicles influences the economically optimal investments and optimal operation of the power system. This work presents analysis of the optimal configuration and operation of the integrated power and road transport system in Northern Europe, i.e. Denmark, Finland, Germany, Norway, and Sweden using the optimization model, Balmorel, with a transport model extension. A number of scenarios have been set up, including sensitivity on CO 2 and oil prices, inclusion/exclusion of electric drive vehicles, and change in investment possibilities in flexible power plants. Plug-in hybrid electric vehicles are shown to be competitive in all scenarios except the low oil scenarios. The increased electricity consumption for the electric vehicles is covered by wind power in Denmark and Norway and by coal production in Finland and Germany. The competition between wind power and coal is dependent on fuel price and CO 2 price assumptions. Furthermore, introducing the flexibility of electric drive vehicles helps decrease cycling on the remaining power plants. Finally, the electric drive vehicles can replace the use of both heat storage and electric boilers as well as decrease the use of gas turbines.

The aim of the project is to analyse the potential synergistic interplay that may arise between t... more The aim of the project is to analyse the potential synergistic interplay that may arise between the power sector and the transport sector, if parts of the road transport energy needs are based on electricity via the utilisation of plug-in hybrid electric vehicles and pure electric vehicles.

ABSTRACT Assessing grid developments the spatial distribution of the electricity consumption is i... more ABSTRACT Assessing grid developments the spatial distribution of the electricity consumption is important. In Denmark the electricity grid consists of transmission - and local distribution grids with different voltages that are connected via transformer stations each covering a local area with between 10.000 and 100.000 customers. Data for the hourly electricity consumption at transformer stations shows that the profile of consumption differs considerably between local areas, and this is partly due to a different weight of categories of customers in the different areas. Categories of customers have quite distinct consumption profiles and contribute quite differently to the aggregated load profile. In forecasts, demand by categories of customers is expected to develop differently implying that both the level and the profile of consumption at each transformer stations are expected to change differently. Still, in the previous planning of the transmission grid in Denmark specific local conditions have not been considered.

European Journal of Operational Research, 2014

ABSTRACT For electricity market participants trading in sequential markets with differences in pr... more ABSTRACT For electricity market participants trading in sequential markets with differences in price levels and risk exposure, it is relevant to analyze the potential of coordinated bidding. We consider a Nordic power producer who engages in the day-ahead spot market and the hour-ahead balancing market. In both markets, clearing prices and dispatched volumes are unknown at the time of bidding. However, in the balancing market, the market participant faces an additional risk of not being dispatched. Taking into account the sequential clearing of these markets and the gradual realization of market prices, we formulate the bidding problem as a multi-stage stochastic program. We investigate whether higher risk exposure may cause hesitation to bid into the balancing market. Furthermore, we quantify the gain from coordinated bidding, and by deriving bounds on this gain, assess the performance of alternative bidding strategies used in practice.

Energy, 2011

Integrating the power and transport system, in the future energy system planning, influences the ... more Integrating the power and transport system, in the future energy system planning, influences the economically optimal investments and optimal operation of the power system as well as the transport system. For analysing the integrated power and transport system a new model capable of calculating optimal investments in both power plants and vehicle technologies is presented in this article. The model includes the interactions between the power system and the transport system including the competition between flexibility measures such as hydrogen storage in combination with electrolysis, heat storage in combination with heat pumps and heat boilers, and plug-in electric vehicles.

Energy, 2012

ABSTRACT In this study, it is analysed how a large-scale implementation of plug-in hybrid electri... more ABSTRACT In this study, it is analysed how a large-scale implementation of plug-in hybrid electric vehicles and battery electric vehicles towards 2030 would influence the power systems of five Northern European countries, Denmark, Finland, Germany, Norway, and Sweden. Increasing shares of electric vehicles (EVs) are assumed; comprising 2.5%, 15%, 34%, and 53% of the private passenger vehicle fleet in 2015, 2020, 2025, and 2030, respectively. Results show that when charged/discharged intelligently, EVs can facilitate significantly increased wind power investments already at low vehicle fleet shares. Moreover, due to vehicle-to-grid capability, EVs can reduce the need for new coal/natural gas power capacities. Wind power can be expected to provide a large share of the electricity for EVs in several of the countries. However, if EVs are not followed up by economic support for renewable energy technologies, coal based power will in several cases, particularly in the short term, likely provide a large part of this electricity. The effects of EVs vary significantly from country to country and are sensitive to fuel and CO2 price variations. The EVs bring CO2 reductions of 1–6% in 2025 and 3–28% in 2030 while total costs are generally increased.

Applied Energy, 2012

Increasing focus on sustainability affects all parts of the energy system. The future integration... more Increasing focus on sustainability affects all parts of the energy system. The future integration of the power and road transport system due to the introduction of electric drive vehicles influences the economically optimal investments and optimal operation of the power system. This work presents analysis of the optimal configuration and operation of the integrated power and road transport system in Northern Europe, i.e. Denmark, Finland, Germany, Norway, and Sweden using the optimization model, Balmorel, with a transport model extension. A number of scenarios have been set up, including sensitivity on CO 2 and oil prices, inclusion/exclusion of electric drive vehicles, and change in investment possibilities in flexible power plants. Plug-in hybrid electric vehicles are shown to be competitive in all scenarios except the low oil scenarios. The increased electricity consumption for the electric vehicles is covered by wind power in Denmark and Norway and by coal production in Finland and Germany. The competition between wind power and coal is dependent on fuel price and CO 2 price assumptions. Furthermore, introducing the flexibility of electric drive vehicles helps decrease cycling on the remaining power plants. Finally, the electric drive vehicles can replace the use of both heat storage and electric boilers as well as decrease the use of gas turbines.

The aim of the project is to analyse the potential synergistic interplay that may arise between t... more The aim of the project is to analyse the potential synergistic interplay that may arise between the power sector and the transport sector, if parts of the road transport energy needs are based on electricity via the utilisation of plug-in hybrid electric vehicles and pure electric vehicles.