###### Abstract  
This paper investigates the future role of cross-border electricity flow between Great Britain (GB) and its neighbors until 2030, considering high deployment of renewable energy sources (e.g., wind, solar, and biomass), enhanced interconnection capacity, and a partly electrified heating sector. It was assumed that two cross-border interconnectors links will connect GB's power system to its neighbors: (1) a one-way interconnector (IC1) that imports electricity to GB, and (2) a two-way one (IC2) between France and GB. The IC2 was allowed to transfer electricity from a cheaper power system to a more expensive one. The results show that at a fixed CO\({}_{2}\) price, a change in power imported via IC1 will affect the power dispatch of the CO\({}_{2}\) emitting power plants and biomass-fired power plants, and electricity trade via IC1 and IC2. At IC1 importing of _E60_/MWh, by raising the CO\({}_{2}\) price from 60 to _E70_/ton, the share of CCCT power plants will reduce by 75%, and the power imported via IC1 link will face 19-times growth. With a constant IC1 import price, raising the CO\({}_{2}\) tax will reduce the total quantity of electricity being exported to France via IC2. Moreover, increasing the CO\({}_{2}\) tax will increase the emissions cost of gas and coal-fired generators, and the power required to meet the demand will be imported via IC1. With the IC1 electricity price set to _E20_/MWh and the CO\({}_{2}\) tax set to _E50_/ton, there may be 595 periods out of 17,520 in which GB will be used as an electricity trade corridor. GB's total CO\({}_{2}\) emissions should drop as the CO\({}_{2}\) tax increases. electricity interconnection; merit order; electricity trade; CO\({}_{2}\) emission; renewable energy +
Footnote †: journal: Applied Sciences  
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Footnote 1: email: [EMAIL_ADDRESS]  
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and Scotland. The latter case tends to increase social welfare. However, from a merchant point of view, none of the interconnection links are profitable. The costs, benefits, and effects of integrating interconnectors with North Sea offshore wind farms were examined by [PERSON] and co-workers [5]. The authors considered three case studies for the UK, Norway, Denmark, Belgium, Germany, and the Netherlands. In addition, CAPEX and OPEX (capital and operational costs) of the system, together with the potential benefits of the integrated projects, were quantified. For each of the three case studies, the conventional designs and the integrated networks were developed and analyzed. The authors claimed that the integrated systems are more advantageous than the conventional power systems. In [6], [PERSON] et al. studied the Greek electricity generation expansion within 2009 and 2020 to reach the planned 40% share of renewables. The renewable installed capacity in 2009 was 1.18 GW. The authors examined the impacts of increasing the capacity of the Greek interconnectors, in addition to increasing storage capabilities, on the expansion of the power system and the system's reserve requirements. The results showed that nearly 8.8-9.3 GW of renewable energy sources, including wind farms, small hydropower, solar PVs, and biomass-fired generators, would have had to be installed to meet the 40% renewables target in 2020. Nepal and [PERSON] assessed the potential roles of interconnectors and enhanced market integration between the Irish market and the electricity markets of other European countries [7]. No integration benefit was reported for integration between the Irish electricity market and those of GB and Elspot. The integration of GB's and SEM's electricity markets was found to be nearly 17%. [PERSON] et al. developed a mixed-integer linear programming (MILP) model to determine the capacities and locations of new electricity interconnectors for GB, Germany, the Netherlands, Belgium, France, Ireland, and the East and West regions of Denmark [8]. The results revealed that cross-border electricity interconnectors tend to reduce the total system costs when there is a renewable electricity generation target.