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29
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Introduction
Skills and Expertise
Current institution
Svenska Kraftnät (swedish TSO)
Current position
- Analyst
Publications
Publications (29)
We show that Swedish wind turbines constructed before 2007 lose 0.15 capacity factor percentage points per year, corresponding to a lifetime energy loss of 6%. A gradual increase of downtime accounts for around one third of the deterioration and worsened efficiency for the remaining. Although the performance loss in Sweden is considerably smaller t...
Output from meteorological reanalyses are used extensively in both academia and industry for modelling wind power. Recently, the first batch of the new ERA5 reanalysis was released. The main purpose of this paper is to compare the performance of ERA5 and MERRA-2 (a commonly used reanalysis today) in terms of modelling i) the aggregated wind generat...
When analyzing power systems, it is often desirable to visualize the network of buses and branches. Here, a new algorithm for producing 2-D network layouts is proposed. The method consists of two steps: first, a matrix of desired distances between all bus-pairs is computed based on base voltages and branch reactances and, second, coordinates that m...
Ethiopia has huge wind energy potential. In order to be able to simulate the power system operation, hourly time series of wind power is needed. These can be obtained from ERA5 data but first a realistic model is needed. Therefore, in this paper ERA5 reanalysis data were used to model wind power production at two topographically different and dista...
Network reduction techniques are very useful for taming the complexity of simulating large interconnected power systems. In this paper, we present the implementation of a tool that performs a multi-area spatial network aggregation based on the generalized Radial Equivalent Independent (REI) methodology. The tool is integrated in Spine, an open sour...
Although regular curtailment of wind power has not been necessary in the Nordic power system so far, rapidly increasing wind power capacity means that it may be needed in the future. To estimate the amount of curtailment in the future Nordic power system we develop an hourly dispatch model based on open data. The model is validated against historic...
S1.1. Wind resource map A preliminary study on the potentials of wind energy across the nation was conducted. The spatial distribution of the annual mean wind speed within the whole country where calculated based on the numerical flow simulations with the three-dimensional atmospheric model KLIMM [1]. As shown in Fig. S1, the wind map confirms the...
100% renewable energy systems require high penetration of variable renewable electricity (VRE) generation. This causes the net load in the system to be more variable and could cause operational problems in local power grids. Demand side management (DSM), such as fuel or energy carrier switching in response to a price signal, can provide flexibility...
A good understanding of forecast errors is imperative for greater penetration of wind power, as it can facilitate planning and operation tasks. Oftentimes, public data is used for system studies without questioning or verifying its origin. In this paper, we propose a methodology to verify public data with the example of wind power prognosis publish...
In this report, performance trends of Swedish wind turbines (WTs) are analysed. During the first years of operation, the production is nearly constant, but subsequently it begins to decline. WTs constructed before 2007 lose around 0.15 capacity factor percentage points per year in absolute terms, corresponding to a life-time energy loss of 6%. A gr...
Increasing the share of intermittent renewable energy (IRE) resources such as solar, wind, wave and tidal energy in a power system poses a challenge in terms of increased net load variability. Fully renewable power systems have previously been analysed, but more systematic analyses are needed that explore the effect of different IRE mixes on system...
When wind power and other intermittent renewable energy (IRE) sources begin to supply a significant part of the load, concerns are often raised about the inherent intermittency and unpredictability of these sources. In order to study the impact from higher IRE penetration levels on the power system, integration studies are regularly performed. The m...
The correlations between wind power generation in different countries are important for quantifying the reductions in variability when electrically interconnecting the countries. Hourly, country-wise time series of wind power output were generated for all European countries using MERRA reanalysis data. By comparing the model output with actual meas...
In wind integration studies, sub-hourly, load synchronous wind data are often preferable. These datasets can be generated by a hybrid approach, combining hourly measurements or output from meteorological models with a stochastic simulation of the high-frequency fluctuations. This paper presents a method for simulating aggregated intra-hourly wind p...
When performing wind integration studies, synthetic wind power forecasts are key elements. Historically, data from operational forecasting systems have been used sparsely, likely due to the high costs involved. Purely statistical methods for simulating wind power forecasts are more common, but have problems mimicking all relevant aspects of actual...
A previously developed model based on MERRA reanalysis data underestimates the high-frequency variability and step changes of hourly, aggregated wind power generation. The goal of this work is to restore these fluctuations. Since the volatility of the high-frequency signal varies in time, machine learning techniques were employed to predict the vol...
This paper presents an evaluation of using the MIUU mesoscale model to predict mean wind speed at 10 meters above ground. This was done by comparing the model output to 128 meteorological measurements in Sweden. Although some terrain-dependent bias was seen, the model worked surprisingly well. Mean absolute error (MAE) was 0.58 m/s or 0.52 m/s if a...
![Figure 1. Comparison of installed capacity in scenario from Ref. [4]...](profile/Jon-Olauson-2/publication/278390531/figure/fig1/AS:668867785404434@1536481915837/Comparison-of-installed-capacity-in-scenario-from-Ref-4-with-actual-outcome_Q320.jpg)
The introduction of large amounts of wind power is a challenge for the operation of the power system. In order to facilitate future studies of the effects of significantly higher penetration levels, scenarios and accompanying time series of hourly wind power production in Sweden were developed. The annual production in the scenarios range from 20 t...
Integrating variable and non-dispatchable renewable power generation into existing power systems will have consequences for their operation and future expansion. These impacts will depend on two factors: (1) the variability of the total renewable power generation on different time scales and (2) the possibilities of accurately forecasting these flu...
The variability of wind power will be an increasing challenge for the power system as wind penetration grows and thus needs to be studied. In this paper a model for generation of hourly aggregated wind power time series is described and evaluated. The model is based on MERRA reanalysis data and information on wind energy converters in Sweden. Insta...
During recovery and reconstruction after a natural disaster, an autonomous power supply might be needed for an extended period of time. In this work, the feasibility of using small-scale wind power and battery storage for power supply is evaluated and compared with systems containing photovoltaics. The investment cost per yearly produced kWh and fo...
Wind power can be related to natural disasters in several ways. This licentiate thesis gives some background and introduces four papers devoted to two aspects of this relation. The first section looks into how small-scale wind energy converters (WECs) could be used to generate power after a natural disaster. For this application diesel generators a...
Questions
Question (1)
I am simulating a non-stationary process and want to evaluate if this is done successfully. It is not possible to simulate the actual values, but the varying variance should be captured. Now I use the correlation of moving averages of absolute measured and simulated data as a goodness metric, does anyone have a better suggestion? See link below for an example.
