Technology
Net Zero: What Does the Data Say?
Research from North Lanarkshire Council has sought to quantify the performance of 19 net zero homes built within a program of 150 new council properties, gathering data from an array of environmental sensors installed within the homes. The homes were built were built with fabric efficiency measures and technologies beyond standard newbuild requirements, including triple glazing, additional insulation, photovoltaic panels, battery storage, and heat pumps.
The report served a dual purpose, aiming to reveal how the net zero homes performed on a day-to-day basis, and as well as the efficiency of data recorded in understanding differences between housing types, identifying patterns in indoor environmental conditions and energy use, and interpreting these findings considering household routines and behaviours.
Methodology
The research required a mixed-methods approach combining quantitative monitoring data with qualitative and survey based behavioural evidence. The project drew on four main categories of data:
Monitored / environmental data: indoor environmental data, relating primarily to conditions such as temperature and co2, alongside energy and property data where possible.
Economic data: relating to construction cost information for the Net Zero homes.
Contextual / property data: relating to dwelling type, housing cohort, heating system, and basic property characteristics.
Behavioural data: relating to occupier experiences, heating and ventilation practices, comfort, satisfaction, and everyday household routines.
The report does concede some shortcomings in the data gathered and the analysis that was carried out. One of the report’ s goals of understanding household heat demand through gathered sensor data was less able to be implemented as the research intended, which led to a gap in behavioral data to enable a thorough analysis of heat demand.
Rather than producing robust heat-demand index as originally intended, the monitored data was instead used to examine patterns in environmental conditions, to compare relative performance across cohorts where possible, and to assess the practical strengths and limitations of the available monitoring approach.
Available data to understand space and water heating demands was also limited, as well as gas consumption data also having difficulties. The lack of complete overall data limited the original scope of the report, but the research undertaken was still able to give some insight into the into the in-use performance of dwellings.
Key findings
Overall, the study indicated effective housing improvement programmes need to address both the physical performance of homes and the circumstances and practices of households. Effective improvement programs should combine fabric and system upgrades with financial support, household advice and follow-up guidance where necessary in order to achieve reliable improvements in comfort, affordability, and energy performance across the housing stock.
Building fabric was found to be crucial when it comes to resident experience and outcomes. Households in well-insulated homes were able to benefit from comfortable stable temperatures with consistent, relatively low heating output, even when compared with homes with more net zero technology. The findings highlight the need for technology such as heat pumps to be
12 Issue 28