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In the past decade, the global share of fossil-based electricity generation has decreased from 67% to 61% in favor of renewable alternatives. To achieve global goals, a continued extensive expansion of electricity generation from renewable energy sources is necessary. Offshore wind power is expected to constitute a significant portion of this additional generation capability. However, intermittent energy generation like wind or solar power has negative impacts on the electricity grid due to its inherently variable and non-dispatchable nature. Furthermore, energy generation from renewable energy sources is characterized by low utilization and requirement of large geographical areas.

One way to mitigate several of these negative aspects is by co-locating energy sources with complementary characteristics. Combining different types of complementary renewable energy sources can reduce overall variability, increase transmission system utilization, and decrease land use. This thesis addresses several aspects of grid integration of offshore co-located energy sources, primarily, offshore wind power, floating solar power, and wave power. One question analyzed in several of the included studies is the optimal combination of energy sources for co-location to achieve the lowest variability.

Another aspect investigated is the capacity credit for a hybrid park consisting of co-located energy generation compared to the capacity credit for a wind farm. In a case study for the Netherlands, the capacity credit for combined wave and wind power is higher than for wind power alone. Additionally, the complementarity of renewable energy sources is analyzed and explained.

E-mobility is pivotal in enabling sustainable and technologically advanced urban environments. In line with this, Sweden's electric vehicle fleet is rapidly expanding, thereby increasing the power necessary for charging electric vehicles. If not properly managed and controlled, this increase in power can potentially threaten grid stability and exacerbate grid congestion. 

The primary aim of this thesis was to assess and investigate the potential of a next-generation parking facility at a multifunctional building to be an active part of the city’s distribution grid. The research was guided by the question of to what capacity smart control of a parking facility with a technical system could assist and alter the load demand to generate benefits for both the building and the city’s distribution grid.

This was investigated at Dansmästaren, the first multifunctional building in Uppsala, Sweden. An experimental setup with an electric vehicle charging station and an energy management system was developed at the Ångström laboratory to test and verify control strategies before their implementation at the multifunctional building's parking facility. Thereafter, a second energy management system was developed and implemented at Dansmästaren with the purpose of monitoring and controlling the electric vehicle charging at the parking facility.

The findings of the included papers were divided into two categories. The charging of the electric vehicles can either be assisted by the parking facility's technical system or altered by including the electric vehicle charging in the control for the technical system. Both categories show that a parking facility with a technical system in a multifunctional building can help reduce local grid demand while also providing local benefits for the building.

While the contribution of a single multifunctional building may appear negligible from a grid perspective, the cumulative effect becomes substantial when applied across multiple buildings. Thus, the parking facility at Dansmästaren has the potential to play an active role in the city’s distribution grid through smart charging and the utilization of an energy management system.

The ongoing transition to a net-zero emissions energy system is driven by what can be called a fourth wave of electrification, where fossil fuel-dependent processes are increasingly replaced by electric-powered appliances. At the same time, a substantial rise in electricity production is coming from renewable energy sources. Both developments are critical for a successful energy transition over the coming decades. A key aspect of this transition is understanding the load demand of electricity users.

The aim of this thesis is to analyze and assess the impact of different electricity users on the local grid, focusing on their consumption behavior. Conducted in collaboration with Uppsala Municipality, the research emphasizes a public perspective, user-friendliness, and a technologically-agnostic presentation of results. Three research objectives have been pursued throughout the thesis: (1) analyzing the impact of a single user's behavior in detail on the grid, incorporating peak shaving and distributed energy resources, in addition to a broader analysis to assess multiple users through a peak load correlation analysis; (2) proposing a framework to generate typical load profiles for various users, using time series clustering and a qualitative clustering step to model their demand patterns throughout the year; and (3) designing an index to quantify and compare the flexibility potential of electricity users, based on a rankable index developed using limited information.        

The results reveal considerable variation among users in both peak load contributions and flexibility potential. The peak load analysis and the flexibility index both identify users that could benefit from behavioral changes or offer potentially valuable flexibility to support grid stability. To test the framework of generating typical load profiles, a case study of elementary schools in Uppsala Municipality was conducted that showed that these institutions exhibited similar load patterns. The most typical load profile was rescaled to represent load variability based on the heated indoor area of an arbitrary school, showing a reasonable accuracy. These profiles can inform the selection of distributed energy resources, such as photovoltaic systems, or facilitate the co-location of users with complementary consumption patterns to minimize grid impacts.

The methods, tools, and frameworks presented in this thesis are versatile and can serve as valuable inputs for strategic decision-making by municipalities, businesses, and other stakeholders. By providing insights into user behavior, these tools can guide focused interventions to support the continued evolution of the energy transition.