Renewable and zero direct emissions heating systems in affordable housing projects (phase 2): evaluation

1. Introduction

1.1. Context

A major challenge that must be addressed to meet Scotland's target of net zero greenhouse gas emissions by 2045 is the decarbonisation of heat in buildings. The incoming New Build Heat Standard (NBHS) will prohibit the use of direct emissions heating systems in new buildings, both domestic and non-domestic, from 2024. The changes to domestic building standards under the incoming NBHS will affect many stakeholders within the new build housing sector, including private developers, Councils and Registered Social Landlords (RSLs).

A non-direct emission heating system, i.e., a zero direct emission heating system (ZDEH), is one which produces zero direct greenhouse gas emissions (at the point of use) under normal operating conditions. The standard is technology neutral, but examples of technologies included in this scope are direct electric systems, air source heat pumps (ASHPs), ground source heat pumps (GSHPs), water source heat pumps (WSHPs), and district heat networks (DHNs). Currently, DHNs that provide heat from gas and other fossil fuels are understood to meet the ZDEH classification, as they do not emit greenhouse gases at point of use, and the emissions from the heat source for a DHN will be considered in separate regulations.

1.2. Research aims

The Scottish Government has appointed Locogen to deliver the second phase of the evaluation of renewable and zero direct emissions heating systems in Scottish affordable housing projects. The first phase of this work was conducted by Locogen in 2021 and helped to formulate the goals of Phase 2. The goals of this second phase of the evaluation are:

• To collect actual (as opposed to estimated) performance data from Affordable Housing projects with zero direct emissions heating systems, including technology performance; operational costs; and occupant satisfaction.
• To advise on the creation of a knowledge-sharing hub where information and best practice guidance can be accessed by stakeholders in the Scottish housing sector, to help them achieve compliance with the NBHS.
• To develop case studies of exemplar zero direct emissions heating in Scottish housing projects, providing insight on system performance, tenant experiences and network constraints.