Within the established SUNEX modelling framework, the end-use and bottom-up model MAED-City (Model for evaluation of energy demand of City) has been used to project future long-term final energy demand of the considered city for the period 2016-2050. MAED-City has been adapted and extended form AIT based on the IAEA energy demand model . The applied end-use concept disaggregates the city energy demand by sector of consumption comprising building (household and service), agriculture, construction, manufacturing industry and transportation (of freight and passenger) . The boundaries of the considered “city energy system” are defined by the administrative boundaries of the city for which the energy balance is provided, i.e., energy consumption of all sectors within the city boundaries. Considering the limited energy resources within the city boundary, the energy supply needed to cover the city energy demand is mainly provided by energy import from outside. However, with the desired increase of local renewable energy generation to cover power and heat demand, many cities will increase their self-sufficiency within the coming decades and thus contribute to the overall sustainable energy development.
As demonstrated in diagram, each energy consumption sectors can be flexibly disaggregated into various sub-sectors in respect to the type of end-use activities and the related socio-economic and technological determinants driving the energy demand. With focus on estimating the energy demand for local food provision -from the local agricultural production up to food delivery- the disaggregation of end-use sectors reflect this fact by defining sub-category for urban agricultural production, food & beverage industry, food retail and wholesale, catering, and hospitality services. Further, the energy demand for cooking and water heating at residential sector are separately considered as part of the household energy demand that covers all categories to provide household energy services of space heating, water heating, cooking, and appliances. The energy demand for transporting food and water -within the city boundaries- are estimated under the freight transportation. The resulting end-use activities of four consumption sectors describing city energy demand are presented in diagram.
Methodological approach of scenario development
The applied co-creation process in developing future energy development scenarios is presented in figure below. The process involves the city stakeholders (via workshop, bilateral discussions, official documents on city future development). It starts with the data collection and reconstruction of base year followed by future visioning (storyline development), construction of future development scenarios, running the model and extracting the results in an iterative process. The results are further monitored and evaluated based on selected key indicators that are aligned to the official energy and climate goals of the considered city.
The applied bottom-up approach of MAED-City model systematically relates the specific energy demand for producing various goods and services to the corresponding social, economic and technological factors affecting the demand for a particular energy form. The main groups of these determinants entail current state and future development of:
- population, dwelling size, electrical appliances used in households,
- peoples’ mobility and preferences for transportation modes,
- GDP (of the considered city or region) priorities for the development of certain industries or economic sectors,
- efficiency of processes, technologies, appliances and equipment,
- penetration rate of energy forms and new technologies.
The demand analysis starts with the reconstruction of a base year defined in this work with the year 2016 as to reflect current energy consumption state. Using the city energy balance for 2016 in terms of final energy consumption by sector and fuel and the set of socio-economic and technological parameters the base year is reconstructed. The reconstruction refers to calibrating the established mathematical relationships between energy demand and related demographic, socio-economic and technological drivers. Detailed elaboration on these deliverables is provided in deliverable D2.1.
With the reconstruction of the base year the concept of MAED-City provides a systematic framework to evaluate the impact of changes in demographic, social, economic and technological drivers on the future energy demand up to 2050.
The expected future trends for the key determinants, which constitute “scenarios”, are exogenously introduced based on official references (e.g., city future development strategy like SCWFS), stakeholder workshops, bilateral communications with the city stakeholder and expert judgements. Each scenario starts with a storyline describing the future vision of the perceived development path. The key aspect in the scenario development is to ensure internal consistency among the different assumptions of the key drivers. Considering that the resulting future energy demand is just a reflection of these assumptions (Figure above). Within SUNEX project two development scenarios have been considered -a business as usual (BAU) and a sustainable development scenario (SDS)- describing expected city’s future socio-economic and technological development for the period 2016-2050.
The next step is developing future scenarios, specific to a to a region´s situation and objectives. The scenarios can be sub-divided into two sub-scenarios:
- BAU (business as usual): BAU describes a continuation of historical development path including recent FWE policy trends without additional measures on sustainable development. BAU serves as benchmarking against which the effectiveness of the applied measures in SDS are evaluated;
- SDS (sustainable development scenario): SDS describes a transformation path towards efficient, sustainable and low-carbon FWE-systems. It aims also to harness existing synergies of FEW-systems. Aligned to the considered city’s future vision, SDS seeks to contribute to achieving inclusive, safe, resilient and sustainable urban development by promoting the efficient use of FWE resources and reducing related CO2 emissions while achieving a long-term sustainable energy strategy. Moreover, some of the demo cities (Vienna and Bristol) have clear objectives of city decarbonise by 2050. Those ambitious targets will be realised by inclusive set of measures including amongst others the significant improvement of energy efficiency, increasing the share of local renewable, electrification and penetration of clean fuel in the final energy consumption.
Main steps for modelling and projection of future final energy demand
Starting from the current energy demand situation of the considered city-region reflected in the selected base year (e.g. 2016) the future final energy demand will be projected based on scenarios reflecting socio-economic and technological development of the considered city region using the tool MAED-City based on the following steps:
- Disaggregation of final energy demand of the city-region by the end-use categories for the base year 2016 represented by consumption sector (household, service, industry and transportation) and final energy form.
- Data preparation for current energy consumption of the considered city-region based on available official data and additional regional and international references. The interaction with the stakeholders via workshop organization and direct communication is essential for data collection, provision and final preparation. Moreover, the stakeholder’s involvement is vital for the later stage of scenario development within the formulation of sustainable FWE strategies.
- Identification of demographic, social, economic and technological drivers determining the energy demand of city-region by end-use categories, e.g. population, dwelling size and type, GDP value added of industry and service activities, inter- and intracity mobility of passengers and freights, penetration rate of different fuel carriers and the end-use conversion technologies.
- Reconstruction of the base year 2016 energy demand by calibrating the established mathematical relationships between energy demand and related demographic, socio-economic and technological drivers.
- In co-design with local stakeholders and urban decision-makers (see WP 3, WP4) consistent development scenarios (BAU and Sustainable Development Scenarios: SDS) are constructed based on the expected future socio-economic and technological development of the considered city-region for the period 2016-2050 and with 5 years step. In contrast to the BAU which reflects the business-as-usual trend, SDS should ensure integrated sustainable energy development path. It should also ensure capturing synergies through FWE-nexus and by integrating the target of related UN-SDGs (Goals 7, 6, 2, 11 and 12).
- Evaluation of the results of the projected final energy/water/food demands and generating related indicators.