19th WORLD CONFERENCE OF THE ASSOCIATED RESEARCH CENTRES FOR THE URBAN UNDERGROUND SPACE, Belgrade, Serbia, November 4-7, 2025. (Paper No: 1.6.214, pp. 69-77)
АУТОР(И) / AUTHOR(S): Jeremy Harrall, Daniel Kastner, Alvaro Garcia, Max Lee
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DOI: 10.46793/ACUUS2025.1.6.214
САЖЕТАК / ABSTRACT:
This paper is a sequel publication to ACUUS 2023, ‘Reservoirs of Heat: A defining characteristic of high thermal mass earth-sheltered buildings.’
Featured below is an advanced analysis of the second case study of the former paper, the nine earth-sheltered homes known as Howgate Close, in the Nottinghamshire village of Eakring.
Reviewed in this paper is the hypothesis, ‘to what extent can energy autonomy be achieved in one of the naturally heated Howgate earth-sheltered homes?’. This evidence-based enquiry is essential in optimising built-in energy security for the future building performance for the balance of eight Howgate homes.
Emerging from Howgate is the advent of a new building paradigm in the UK. One where the level of energy autonomy at Howgate is delivering a net daily cash surplus for the home with a battery installed. As a consequence, there are no more energy bills, relegating the threat fuel-poverty to a distant memory. This is a continuous process of ‘marginal gains’
What difference a battery makes?
Batteries in buildings, facilitate energy storage and can be thought of as ‘reservoirs of energy’.
This paper introduces in-use building performance data from a 1bedroom earth-sheltered dwelling, pre-and-post battery installation. Also discussed, are the wider-ranging impact batteries have in reducing the burden of energy bills.
After the first three years of occupation, the selected 1bed home has exceptionally low average daily total energy costs that are less than 45pence/day (inclusive of Standing Charge). Before the battery install, the home consumed 7KWhrs/day imported energy from the grid and exported 13.5KWhrs/day to the grid.
The next stage of Howgate Close’s development is the inclusion of energy storage facilities to all nine homes. However, the first phase has been to install an 11KWhr BYD battery and a Fronius hybrid inverter to one of the 1bed dwellings. At the time of submitting the full paper, sixteen weeks of in-use building performance data has been gathered. Results from 16.04.2025 to 13.08.2025 record in excess of 50% reduction in daily energy consumption from the grid compared to the same period in 2024.
This paper will add to the accumulating, independent, evidence-based research from the nine earth-sheltered homes of Howgate Close. Additional empirical data is provided in support of the premise that, ‘high thermal mass buildings should be the building form of choice in reducing heating/cooling loads together with concomitant energy costs.’
КЉУЧНЕ РЕЧИ / KEYWORDS:
residual heat reservoir, reservoir of energy, earth-sheltered building, energy storage facility, battery, zero heating, thermal mass, passive solar design.
ПРОЈЕКАТ / ACKNOWLEDGEMENT: