Renewable and zero emissions heating systems in affordable housing projects: evaluation

3. Methodology

3.1. Overview

The scope of our research and this report consists of three work packages, as summarised in the overview diagram in Figure 1, which was devised by the Scottish Government. The detailed methodology for the three work packages is detailed in Section 3.2 and the rest of this report summarises our findings. For ease of understanding, work package 2 has been presented first as this ordering allows for the findings from work package 1 to be better understood.

3.2. Detailed Methodology

3.2.1. Work package 1

Work package 1 focussed on collecting cost information from each of the affordable housing projects that participated in the study. The following information was requested from each project:

• Estimated and actual capital cost breakdowns for heating systems
• Estimated comparative capital costs for counterfactual carbon-intensive systems
• Network costs associated with the heating systems
• Heat and hot water demand and annual costs for chosen and counterfactual systems.

Of the 21 projects, 15 were at a sufficient stage of development to provide at least some of this information, and all but two of these shared cost and/or energy demand data. This information was collated for each project and for each heating system technology. Using programme-averaged values, heating system operational and running costs were characterised for four occupancy-based housing archetypes.

3.2.2. Work package 2

Work package 2 involved remote interviews with the representatives of each project to understand the decision-making process that led to the chosen heating systems, as well as the stakeholders' perceptions across several themes, including:

• Choice of technology
• User impacts
• Supply chain interaction
• Innovation

We also conducted interviews with the supply chain to determine their capacity to deliver zero-carbon heating to affordable housing projects. Interviews were held via Microsoft Teams, lasting 30 minutes to an hour. A discussion guide was developed and adhered to in order to ensure continuity of the themes covered in each discussion, whilst allowing for stakeholders to focus on topics that they considered important.

The project stakeholder interviews focussed on identifying the experiences and views of Councils and RSLs on:

• Motivations for low carbon heating
• The decision-making process
• Technology costs
• Network connection issues and costs
• Challenges faced for low carbon heating systems
• Supply chain capacity and capability to deliver
• Plans for monitoring the installations

The supply chain stakeholder interviews focussed on identifying the experiences and views of low carbon technology providers on:

• Barriers to housing developers on choosing low carbon technologies
• Key challenges they face
• Supply chain capacity and capability to deliver
• Critical points in the supply chain
• Products and services offered to housing developers

Lastly, we also met remotely with consultants from Riccardo Energy & Environment and Ramboll in order to ensure cohesion between the findings of this evaluation and their complementary studies for the Scottish Government.

3.2.3. Work package 3

Work package 3 centred on analysing the findings from the two preceding work packages, in order to highlight the most important findings and areas where further study or action is recommended. Locogen has provided rationale and suggested methodologies for recommended areas of investigation, intervention and innovation, to be included in future evaluations.