Delivering sustainable energy transition : A techno-economic analysis on households, businesses and communities of the Keweenaw Peninsula

Sammanfattning: Energy security understood as the practice by which risks associated with interruptions to the energy supply are low, represents one of the main objectives of energy policies in many countries. In this context, Keweenaw County or Michigan's northernmost County is placed as locked in an unreliable, unsustainable and particularly wasteful energy system. The cost of electricity is among the highest in comparison with the national average tariffs, extreme weather makes grid outages commonplace, and the vast majority of both electricity and heat is supplied by fossil fuels. This thesis project aims to identify the most appropriate strategies for the evaluation of alternative and more sustainable energy systems that can replace the current ones. The first phase of the thesis was based on quantifying the energy needs of the analyzed region. To do this, a bottom-up approach based on buildings archetypes has been adopted. At the beginning of the modelling process a new reference building stock, in which different building types and construction periods have been considered, has been designed. Once the energy loads of single buildings have been obtained, the results have been scaled at a community level. In total, three types of consumers have been addressed throughout the following study: individual households, businesses, and communities. System design configurations intended to satisfy requests in terms of lights and electric appliances, space heating and cooling, cooking and service hot water have been examined. Energy supply technologies such as solar photovoltaics (PV), storage, air source heat pumps (ASHP), ground source heat pumps (GSHP) and small-scale biomass combined heat and power (CHP) units are analyzed. Multiple electrification levels, from baseline to more advanced configurations where electricity represents the only energy carrier are evaluated. A different approach is adopted at community scale where different scenarios are discussed. Technical feasibility and economic viability of each electrification level in the case of residential and commercial sectors as well as of community related scenarios are tested. The costs and benefits of implementing this electrification strategy and a decentralized energy scenario are quantified by means of key performance indicators (KPIs) such as total life cycle costs, primary renewable energy fraction (PREF), annual CO2 emissions, primary energy intensity (PEI) and levelized cost of energy (LCOE). Ultimately, the results obtained from the simulations suggest the concrete possibility of an energy transition towards sustainable energy systems based on distributed generation. In detail, heat pumps coupled with solar PV represents a more sustainable and cost-efficient alternative to traditional fossil-based heating. The most advanced electrification levels analyzed, are configured as the most promising options for all buildings, in particular in the forecast of technologies cost reductions and lower electricity rates. However, several obstacles to their deployment are currently present. Accordingly, a business model innovation designed to unlock these sustainable energy systems is explored.