Intraday includes the continuous and auction market. The duty of that is to upgrade and adjust unbalancing after the day-ahead market has shut down. Intraday market is closed until one hour before the actual time. By 2020 nearly 20% of energy is supplied by renewable energies [95]. In the future RES (Renewable Energy Resources) are becoming extraordinary in power networks. So intermittent energies like wind and solar that rely on weather make supplying more fluctuating. On the other side, demand can’t be predicted accurately. So in the total value of intraday market becoming more in the future. Modeling price predicting in the intraday market still needs more works on it.
Because dependency between market variables is following non-linear. Machine learning and artificial intelligence are methods that help the market to perceive statistical formation. Also, they can solve complex data analysis [96]. The interday market is helpful for electricity power balancing but the bidding and prices are diverse with the day-ahead electricity market. Scientists in [97] try to make an economic model for unbalanced prices in the intraday market. They try to make a scheme for the bidding system. They also want to understand how this balancing should be reflected in to supply between consumption.
5.1 Nordic countries
As mentioned before trading electricity in the Nordic area is divided into three markets:
The day-ahead market, intraday market and regulation power dealing. Day-ahead and intraday markets are done in Nordpool[98]. Controllable hydropower is one of the essential factors for the optimization in the day-ahead and intraday market. On the other side, the intraday market doesn’t have much flexibility and control that is urgent in order to intermittent generation. In the day-ahead market, all stakeholders agree and submit offers and bids and by an algorithm settle fees. In advance, the intraday market has a system of cross-border transactions. So all customers and players can sell or buy electricity to adjust their needs. ELSPOT market is the day-ahead market in Nordpool. ELBAS plays a role in intraday [97].
In researches that are done by [97] shows that balancing market price consist of a willingness premium that is higher top of the day-ahead market price. The premium is asymmetric and unbalanced. For instance, the amounts for down-regulated power is lower than up-regulated. This unbalancing motivate all participant in the market to anticipate different than their assumptions in the day-ahead market. So all producer players give lower data to the day-ahead market and consumers submit more than their necessity in the day-ahead market cause it is cheaper for them to buy more in the day-ahead market and sell the extra in the intraday market.
Reference [97] tries to explore the potential and possibility of asymmetric fees in the intraday Nordic market. Also, they figure out to lead this possibility to vital bidding in intermittent resources and customers. Furthermore, they tend to find a price model that is related to balancing market to intraday market.
Article [97] indicates that intraday and day-ahead markets are relevant to each other. A large number of intraday fees are much higher than the day-ahead market. Also, price variations are higher in the intraday market. The size of the intraday is 1.5% of the day-ahead market.
All in all the results from [97] illustrate that the magnitude and sign of whole load settlement have a memorable effect on intraday premium prices. Also, VRE( Variable Renewable Energy) producers can reduce their trading in the day-ahead market. So customers should purchase more than their need in the day-ahead market to be sure that they don’t have a shortage. They can sell extra energy on the intraday market and earn good money. Another result from [97] is that the structure of the fee that Skytte (1999) recommends about the balancing market can’t be interchangeable to the intraday market. At the end of the joint balancing market to the intraday market in Nordic countries, it has to figure out price structure and impacts on all market players.
Intraday data of Nordic countries are open data extracted from the Nordpool website [89]. Intraday price data only demonstrate hourly data. This thesis use extracted data for 24 hours of one day on the 1st of July 2020. It is tried to reveal different prices in each hour of the day in different Nordic zones. In the end, it is compared to day-ahead prices. After that, the average values for the whole of July 2020 are done for comparing and chasing average price values in one month.
Figure 61 demonstrates all Nordic market zones’ hourly intraday market prices on the first of July 2020. There are no data for NO4 on this day. Blue ones are for Denmark, while yellow is for Finland. The green ones are for Norway and the red ones are the sign of Sweden. DK1 and DK2 had similar values. Norway zones (except time 10-14)
had adjacent values. SE4 had the most prices among Sweden zones. All in all prices on one to five in the morning were the least in all countries. Denmark and Finland with only SE4 of Sweden had the highest price. The average cheapest price was for Norway. The biggest sudden jump was for Denmark at 5 AM. The maximum and minimum price of Denmark were 45.72 €/MWh at 8 PM (DK2) and -0.96 €/MWh at 4 AM(DK1). The highest and lowest price in Finland were 46.76 €/MWh at 9 AM and 5.65
€/MWh at 4 AM. The minimum and maximum price of Norway were -1 €/MWh at 1 AM in NO1 and 15.41 €/MWh at 12 PM in NO3. The highest and lowest price of Sweden were 43.5 €/MWh at 8 PM in SE4 and -1.38 at 1 AM in S2. Figure 62 shows average values of zones for each country to make comparing more simple.
Nordic intraday price in all zones on 1st of July 2020 Figure 62 reveals day-ahead and intraday hourly prices for Nordic countries on the 1st of July 2020. It can be seen that most of the time day-ahead prices were less than the intraday price for each country. Also intraday follow the day-ahead pattern, which is ironic cause day-ahead price is estimated from one day before real-time. In intraday, market actors try to justify it close to real-time. Another thing that it is visible is that fluctuations in day-ahead prices were less than intraday prices and day-ahead prices had smoother curves. All prices were at the lowest rate from 1 to 5 AM, which is because of the lowest rate of consumption, at this time for all countries. Norway had the lowest prices in both the day-ahead and intraday market and the reason is using the highest hydropower.
Day-ahead and intraday hourly prices for Nordic countries on 1st of July 2020
Figure 63 demonstrates day-ahead and intraday market prices for the whole of July 2020 for four Nordic countries. As can be seen, intraday prices were mainly more than day-ahead prices in each country. Denmark had the highest intraday and day-ahead price values on most days. After that Finland, Sweden, and Norway respectively had the highest price values. There were some negative prices in Denmark and Norway regions. All day-ahead market prices oscillations were less than intraday market prices.
All countries had low peak prices on the 5th, 11th, and 28th of July. The highest price was in the middle of July. Fluctuation in prices was negligible in Norway (both intraday and day-ahead prices) which may be related to using hydropower. Also, the production was most of the time bigger than consumption in Norway. In contrast, Denmark had the most fluctuation which may cause by the high rate of using wind generation in Denmark.
Day-ahead and intraday prices for Nordic countries for July 2020
5.2 Germany
Germany's intraday market operates with EPEX and EEX market. Market closure time is between 60 to 15 minutes before real-time. ”3 Hour INX” is an indices platform that reveals intraday market price. They are open data in 15, 30, and 60 minutes before
real-time in Nordpool [89]. In this thesis data for 60 minutes before is collected for two purposes. Firstly it is tried to demonstrate intraday and day-ahead price in each hour for a special day (1st of July 2020). After that study the oscillation of intraday prices in one day. In the end, by making some average for every day, monthly price graphs are checked.
Figure 64 represents hourly day-ahead and intraday prices for Germany on the 1st of July 2020. Intraday prices mainly had more values than the day-ahead market.
Maximum and minimum intraday prices were 51.7 €/MWh at 7 PM and 22.14 €/MWh at 2 AM. Day-ahead prices change behaviors were milder than intraday prices. 2 to 5 AM had the lowest and 18 to 21 PM had the highest prices in Germany. Oscillation of the intraday market in Germany was lower than in Nordic countries (except Norway).
Day-ahead and intraday hourly prices for Germany on the 1st of July 2020
Figure 65 demonstrates daily day-ahead and intraday prices for Germany in the entire July 2020. More smoothness of day-ahead and lower price of day-ahead compare to intraday in most of the time can be seen in this graph too. The most and least average intraday price value was 58.91 €/MWh on 16th July and -15.34 €/MWh on the 5th of July. Intraday and day-ahead prices were between 20 to 60 €/MWh on all days except the 3rd to 6th of July which the market faced a sudden drop in prices.
Day-ahead and intraday prices of Germany in July 2020 UK electricity grid and market have some plan for initiating intraday market, but until now there are no data for UK intraday market yet.
The intraday market isn’t defined in the USA and Australia. They have some controlling and adjusting supply and demand before real-time. But they are not auction-based. So this thesis study on the intraday market is only based on Germany and Nordic coun-tries.
All things considered, it can be concluded that intraday and day-ahead markets are relevant to each other. Intraday fees usually are higher than the day-ahead market. It encourages consumers to buy more in the day-ahead market and sell the extra in the intraday market. Price variations are higher in the intraday market. Fluctuation in intraday and day-ahead prices is lower in countries that use more hydropower. Intraday and day-ahead prices are lower in places and times that production is bigger than consumption. Sharing a high amount of wind has an impact on high fluctuations of day-ahead and intraday prices in each country.