nismod2
National Infrastructure Systems Model setup, configuration and tests
CGEN Combined Gas and Electricity Network Model
Model code: nismod/energy_supply (not yet public)
Key reference: Jayasuriya, L. et al. (2019). ‘Energy hub modelling for multi-scale and multi-energy supply systems’, 2019 IEEE Milan PowerTech, PowerTech 2019. IEEE, pp. 1–6. doi: 10.1109/PTC.2019.8810641
Details of model inputs, parameters and outputs:
Notes on data sources:
Description
The energy supply model in the ITRC-MISTRAL programme is based on the Combined Gas and Electricity Network model for Great Britain. [1,2] The ITRC-MISTRAL energy supply model is rebuilt from the ground up and includes characterisation of the energy supply system at both transmission and distribution scales. The energy supply model performs operational analysis over multi-time periods considering electricity, natural gas, hydrogen and heat supply systems and their interactions. [3]
The model minimises total operational costs to meet energy demands across the energy supply system. The operational costs of the energy system are derived from energy supply, emissions and unserved energy. The cost minimisation is subjected to constraints which are derived from the operational characteristics of assets and the supply and demand balance of the energy system.
Energy transmission components in the model are connected to the electricity and natural gas networks. These two transmission networks interact through gas fired power generators. Energy resource supplies, generation technologies and networks are explicitly modelled. Detailed modelling methods are used to represent seasonal gas storage operation, variable generation of renewables and operation of interconnectors. Energy supply at the transmission level meets demands from large industrial consumers and energy flows to the distribution networks. The figure below illustrates a stylised representation of the key electricity and gas transmission system components modelled.
Within energy distribution systems, integrated electricity, natural gas, hydrogen and heat distribution systems are considered. To form the integrated framework of various energy carriers (via energy conversion technologies) an ‘energy-hub’ concept is adopted. The energy hub utilises available regionally distributed energy resources and transmission grid supplies to meet electricity, natural gas and heat demands of residential and commercial consumers. Constraints from each technology component and network energy flow capacities are considered in the model. A simple illustration of an energy hub is shown in the figure below.
The modelling approach in ITRC-MISTRAL offers a rich level of disaggregated temporal and spatial representation of energy supply systems. This allows detailed analysis of future energy supply systems under various strategies such as integration of high levels of renewables, expansion of community and distributed generation, benefits of electrical storage devices, greater consumer participation and the challenge of decarbonising heat and mobility.
Key outputs from the model include the energy supply mix at both transmission and distribution, total emissions from the electricity system and cost of operation. Additionally, the model is also able to offer insights into the impacts of user defined infrastructure expansion options.
Modelling of the Oxford-Cambridge Arc
The energy supply model is utilised to analyse the Arc scenarios alongside specific heat system strategies for the Oxford-Cambridge Arc. This region is modelled using the existing spatial granularity 71 by which the distribution regions are represented. The energy distribution regions are represented by 29 energy hubs as shown in the figure below. Three of these energy hubs (out of 29) characterise energy systems within the Oxford- Cambridge Arc (1: Western-Oxford, 2: Central-Milton Keynes and 3: Eastern-Cambridge)
The energy distribution regions are connected to the transmission networks.
The figure below shows GB electricity and natural gas transmission network representation within the energy supply model.
Model setup
The GB electricity and gas transmission system and 26 energy hubs (i.e. excluding the three energy hubs that represent the Oxford-Cambridge Arc region) follow the generation and network ‘capacity pattern’ (out to 2050) as outlined by the ‘Two Degrees’ Future Energy Scenarios (FES, National Grid 2019). To take account of the differing demand requirements for the Arc scenarios the ‘capacity pattern’ from the ‘FES two degrees’ scenario is sized linearly so that supply matches demand whilst maintaining capacity margins.
The three energy hubs representing the Oxford-Cambridge Arc regions are subjected to various supply side assumptions (technology, resource constraints) to year 2050 which describe various pathways to meet energy demand. Table 3 of the main report illustrates the strategies applied across the three Arc region energy hubs. The strategies were chosen so that they cover a range of possibilities across the Arc, from electrical domination to use of green gases and district heat network solutions. Some of these strategies meet more stringent emission targets than others (i.e. net zero). The heating demand is projected by the energy demand model for years 2015, 2030 and 2050. From the final heating demand, a maximum share is assigned to different technologies for the supply of heat. This is reflected in the maximum installed heat supply capacity for each technology within the Arc region. Distinct heat strategy options were modelled. Technology uptake within these strategy options considered key elements such as maturity, annual build rates, annual and peak heat demand and capacity margin factors.
Model simulation
Each energy supply model run performs operational analysis of the entire energy system for a simulation year. Default model run setup of the energy supply model performs analysis for the whole GB system. The outputs are recorded at regional, and at transmission network level. Within each year, four seasons are modelled with one representative week for each season using hourly time granularity.
References
- Chaudry, M., Jenkins, N. and Strbac, G. (2008). Multi-time period combined gas and electricity network optimisation. Electric Power Systems Research, 78(7), pp. 1265–1279. doi: 10.1016/j.epsr.2007.11.002.
- Chaudry, M., Jenkins, N., Qadrdan, M. and Wu, J. (2014). Combined gas and electricity network expansion planning, Applied Energy 113, pp. 1171-1187. 10.1016/j.apenergy.2013.08.071.
- Jayasuriya, L. et al. (2019). ‘Energy hub modelling for multi-scale and multi-energy supply systems’, 2019 IEEE Milan PowerTech, PowerTech 2019. IEEE, pp. 1–6. doi: 10.1109/PTC.2019.8810641.
NISMOD Energy Supply data
DAFNI dataset: v0.9.12
Includes model configuration for the electricity and gas network in the base year (2015) and possible future interventions - generation, transmission, interconnectors, gas storage and terminals, and heating supply technology options.
Also contains parameters for model sensitivity analysis, historic and future weather/climate time series for insolation and wind speed from the Met Office and Weather@Home (aligned with the temperature time series used to model heating energy demand), price scenarios, and spatial definitions for the energy hub regions, gas nodes and bus bars.
Contains data covered by the Open Government Licence: http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/ Contains National Statistics data © Crown copyright and database right 2012. Contains Ordnance Survey data © Crown copyright and database right 2012.
Contains historic weather station data derived from Met Office (2019): Met Office MIDAS Open: UK Land Surface Stations Data (1853-current). Centre for Environmental Data Analysis, date of citation. http://catalogue.ceda.ac.uk/uuid/dbd451271eb04662beade68da43546e1
Contains future climate time series data derived from Guillod, B.P.; Jones, R.G.; Kay, A.L.; Massey, N.R.; Sparrow, S.; Wallom, D.C.H.; Wilson, S.S. (2017): Managing the Risks, Impacts and Uncertainties of drought and water Scarcity (MaRIUS) project: Large set of potential past and future climate time series for the UK from the weather@home2 model. Centre for Environmental Data Analysis, 17th April 2019. doi:10.5285/0cea8d7aca57427fae92241348ae9b03
All data compiled by Lahiru Jayasuriya and Modassar Chaudry, Cardiff University.