This analytical report by The Kensa Group examines the performance, running costs, and lifetime costs of air-source heat pumps (ASHP) versus ground-source heat pumps (GSHP) with shared loops. It highlights the impact of British weather conditions on efficiency and cost savings, providing insights for future energy strategies. Key findings include significant annualized cost differences and the benefits of shared ground loop systems. This study serves as a vital resource for stakeholders in the r