Bandwidth heating: Exploring temperature ranges for economical heating

Abstract

This thesis investigates how the performance and appeal of heat-pump-fed district heating (HPDH) systems can be improved, offering a sustainable alternative to traditional gas boilers. HPDH systems are important in the transition to renewable energy sources and becoming a low-carbon society, but adoption faces challenges.

Central to the project is the concept of bandwidth heating, in which users agree to a temperature range rather than a fixed setpoint. Research supports how small temperature ranges are perceived as comfortable, at slow drift rates (rate of temperature change). Due to the slow thermal inertia of heating homes, this comfort applies to this design. This flexibility enables a shift of heating draw toward periods of low hourly energy prices and high renewable availability, providing cost savings and additional environmental benefit. Simulation results demonstrate that bandwidth heating can significantly lower heating costs by up to 15% while increasing the share of consumed renewable energy. This dynamic system maintains user comfort in these small fluctuations of temperature, making them a more competitive heating solution. When hourly prices are high, the system coasts. When prices are low, the system allows heating. As influxes of renewable energy exert downward pressure on the energy price, cheap electricity is greener too.

The project introduces a Heating-as-a-Service (HaaS) model, combining the technical optimization with a user aspect. The HaaS model shifts focus from individual ownership to a subscription-based service, through which bandwidth heating is offered. This distinction carries more agency for the system. This approach enables this cost-effective method and brings opportunities for more innovation within this service.

Users are supplied with a novel HaaS interface, through which they can select their preferences and parameters within which the system may optimize. It is developed and tested with users, revealing that most participants are excited about the cost savings bandwidth heating can offer. The interface features more elements such as savings comparisons, social cues and an introductory tutorial to ensure all users are comfortable and knowledgeable of the system. In testing, users noted how automation is welcome if its benefits are evident, so a comparing graph is made part of the interface where the daily consumption of HaaS is compared to a fictional fixed thermostat consumption under similar conditions.
Built with system development, technical modelling in MATLAB, and interface prototyping, the result is a scalable, user-centric product-service system that supports the transition toward smarter, more sustainable heating by making HPDH a more competitive product.