Evaluating the Impact of Altered Electricity Systems

Abstract: In the light of the importance of climate change and the emissions that have induced it, the ability to calculate the effect on emissions by changing transmission capacity is vital. A model to perform such indicative calculations is developed in this thesis. After researching how the current electricity system is organised, the effects on GHG emissions that are expected from increased renewable electricity production and increased transmission are considered. For the model, wind and demand data was processed to form a model of linear dependence between areas. Nuclear and solar power production were assumed to maintain a constant level of generation, whilst bio- and hydro power generation were assumed to be proportional to demand. Carbon data was found by means of a literature search. The algorithm began with a linear optimisation segment, dispatching the cheapest power available. This was followed by a step-wise examination whether transmission capacities could balance out the production over the areas. If deficits remained, a second economic dispatch commenced locally. The results came reasonably close to the expected values in a base case, however a malfunction regarding exchange balances was discovered. A scenario considering the nuclear trends of Sweden, Finland, Germany and the UK gave that the shutdown of nuclear will lead to an increased amount of GHG emissions if all other generation capacities remain. This is likely a trustworthy result as it is mostly determined by the initial dispatch, before exchange balancing displays major faults. A scenario, where all the relevant interconnectors in the ENTSO_E’s 2018 TYNDP were realised, did not however yield carbon savings if the parameters defining the 2018 base case remained. This result may be explained by the additional transmission capacity not being used for additional renewables, rather that cheaper fossil power could travel further. However due to the exchange imbalance this scenario may not be viable at all, as it is more dependent on the parts of the model handling transmission. There are many ways of improving the model, highlights being resolving the exchange imbalance bug, and building better models for demand, wind and hydro power production. After the improvements are made, the model may be capable of the tasks it was designed for.