File Name : pic_s1.tif Caption : lcoh for each case in scenario 1. the bar chart with the error bar at the top shows the lcoh with heat integration. for comparison, gray hydrogen costs are denoted by a dashed line (average) and a gray area (range). the bottom figure presents the lcoh of thermal energy. lcoh and lcohheat in the n-hi case, which is the cost of electric heat, are marked as red circles with error bars at the top and bottom, respectively. File Name : pic_s2_cor.tif Caption : chord chart of the pearson correlation matrix for wind power between eight locations. the width of the chord denotes the correlation coefficient between the two places. the red chord is the lowest correlation for each site. wind power from the other end of a red cord will complement the intermittent wind best. pearson correlation matrix is attached in the esi spreadsheet. File Name : pic_s2.tif Caption : lcoh for each case in scenario 2. the bar chart with the error bar at the top depicts the lcoh with 100 and 200 gwh/y power imported from the super grid. for comparison, gray hydrogen costs are denoted by a black dashed line (average) and area (range). lcoh in an independent grid (red) or purchase 200gwh/y electricity from the market (gray) are illustrated as circle and error bar for reference. the bottom figure presents the cf with and without super grid integration. File Name : pic_deg.tif Caption : lcoh for 19 long term tested soec and one virtual test under 91.3% cf, n-hi, and onshore wind power lcoe. the size of the plot denotes the test time. the longest halfway test lasted 24kh. the most extended start-up test lasted 6kh and was selected for s1 and s2. detailed data is listed in the eis spreadsheet. File Name : pic_s3.tif Caption : lcoh for each case in scenario 3. the bar chart with the error bar at the top depicts the lcoh for future cells that start in 2025 and 2035, respectively. lcoh in scenario 1 is marked as red circles and error bars for reference. for comparison, gray hydrogen costs are denoted by a dashed line (average) and a gray area (range). the bottom figure presents the capital cost for reference and future cell by years.