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This study presents a small scale energy system modelling tool which can be used to plan a secure and economical hourly generation schedule, for a day ahead commitment process in a power system with conventional and wind generation units. The problem solves a unit commitment problem (UC) with operational and transmission system constraints. Simple energy balances or UC solutions obtained without considering power flow constraints are not practical due to secure operation of the power network. With the increasing inclusion of wind generators and other renewable generation, line flows can be altered that may lead to expensive schedules and may not be even feasible at worst. Thus the need for a modelling tool in this context is apparent. The unit commitment problem is formulated to run the optimal power flow dispatch as an integral part of the solution. A forward dynamic programming approach is used to solve for the unit commitment optimization. The unit commitment model is validated using a standard text book case study and the optimal power flow solution using „MatPOWER‟, a tool for power flow analysis. A case study is carried out on the island of Corvo in Azores-Portugal to analyse an existing power network operation along with its future expansion plans in wind power integration. The results are compared with the actual data from Corvo and a HOMER simulation of the same. The algorithms are implemented through a Matlab simulation environment, and the results obtained are quite encouraging. The unit commitment solution was developed in collaboration with a colleague, Abhishek Shivakumar who is working on developing a demand response algorithm in alignment with the larger scope of the same project.

Heating is arguably one of the most difficult sectors to decarbonise in the UK's energy system. Meeting the 80% greenhouse gas emission reduction target by 2050 is likely to require that heat related emissions of CO2 from buildings are near zero by 2050, and there is a 70% reduction in emissions from industry (from 1990 levels). Though it is clear that the use of the natural gas network will reduce over time, recent modelling suggests a limited residual role for gas by 2050 to help meet peaks in heat demand. High levels of uncertainty about the way in which heat will be decarbonised present a number of challenges to policy makers. This paper will explore the risks and uncertainties associated with the transition to a low carbon heat system in the UK as outlined by the 4th carbon budget review. The potential impact of key uncertainties on the levelised costs of heat technologies and the development of energy networks are explored using a sensitivity analysis approach. Policy changes required to decarbonise the heat sector are also examined.

Energy supply systems such as the electricity, natural gas, district heating and cooling networks are typically designed and operated independently of each other. The increasing use of technologies such as combined heat and power units, gas turbines, heat pumps and recently, power to gas systems are increasing the links between energy systems introducing technical and economic interactions. There is a significant interest from academics, industry and policy makers in different parts of the world to identify and realise the opportunities of integrating energy networks while avoiding any undesirable impacts.\ud Analysis of the interdependencies between different energy systems requires powerful software models and analysis tools. However, there are no commercial tools available to date. The aim of this research is to develop a model for the combined steady state simulation and operation planning of integrated energy supply systems. As part of this thesis, three key components of the model were developed i.e.,\ud a) Optimal power dispatch of an integrated energy system: A real case study was used to demonstrate the economic benefits of considering the interactions between different energy systems in their design and operation planning.\ud b) Simultaneous steady state analysis of coupled energy networks: An example of a coupled electricity, gas, district heating and district cooling network system was used to illustrate the formulation of equations and the iterative solution method. A case study was carried out to demonstrate the application of the method for integrated energy network analysis.\ud c) Steady state analysis of gas networks with the distributed injection of alternative gases: A case study was carried out to demonstrate the impact of alternative gas injections on the pressure delivery and gas quality in the network.