Cost efficiency of a highly energy resilient apartment building using heat pumps and increased end user flexibility

Abstract

Owing to a higher standard of living, an increased number of people are living in buildings which leads to more energy consumption in buildings and is simultaneously susceptible to security challenges by natural or man-made activities. The recent IPCC 2022 report and geopolitical situation corroborate the same, thus encouraging the shift to resilient energy buildings. Studies for building resilience have been done but focused only on heating scenarios, with no work about extreme cold climates. Even there is no consensus over terminologies and frameworks to be used. This thesis aims to define terminologies and standardize parameters that can be used to measure building resilience in the extreme cold climate of Finland during the black-out event. The survivability parameters have been defined based on literature and technical specifications. The selected parameters are simulated in IDA-ICE software to analyze thermal decay in apartments during a blackout.

Two building configurations have been simulated, first built according to Finnish regulations and later built with efficient building envelope parameters. Efficient configuration building is more resilient and takes around 15% more time and thermal decay is influenced by the building envelope and exposure to the environment. The power needed in baseline building is almost 4 times of power needed in efficient for varied resilience duration while the energy needed ranges from 4 to 32 times.

The integrated system needs additional investment and due to the highly unlikely situation of a blackout, system operational efficiency becomes very low. There is the possibility of participation in the flexibility market with batteries as they can ramp up and ramp down the power capabilities. The possible revenue is calculated by participation in different flexibility markets in favorable situations. It is found from calculations that with existing electricity prices, there will not be return on investment, but it may be feasible with renewable electricity. It can be inferred based on the increasing number of energy storage plants participating in flexibility services.

Different energy-generation and storage systems are explored including conventional and renewables. Owing to technical specifications, technological maturity, cost, and availability - diesel generators, oil boilers, and lithium-ion batteries are selected to proceed forward with. It has been tried to approach as realistic cost as possible, so cost data from online portals, distributors, and manufacturers have been used with assumptions in some cases of non-availability of data. Cost data for the system shows that the battery occupies the maximum proportion of the cost and increases more with resilience duration. The range of investment needed has been calculated for different resilience duration for the combination of specific components, for example, diesel, boilers, and generators.