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Net-zero buildings, what are they and what they should be?
- Source :
-
Energy . Oct2022, Vol. 256, pN.PAG-N.PAG. 1p. - Publication Year :
- 2022
-
Abstract
- This paper quantifies that current net-zero building definitions will remain as necessary but not sufficient conditions in sustainable decarbonization efforts until they recognize exergy destructions as one of the root causes of emission responsibilities. A direct relationship between exergy destructions and nearly-avoidable carbon dioxide emissions has been set as a sufficient condition to upgrade the decarbonization mindset. This relationship is demonstrated in a case study where a solar prosumer building with photovoltaic panels and a ground-source heat pump, known as a net-zero energy building, is responsible for emissions. Based on the second law, emission responsibilities, primarily at the PV panels and the heat pump, were identified. By replacing them with advanced photo-voltaic-heat panels with temperature peaking and heat pump with adsorption cooling machines, carbon dioxide emission responsibility due to avoidable exergy destructions was reduced by 96%. The main attribute is using solar power only for electric power instead of downgrading it downstream to heat or cold by the heat pump, minimizing exergy mismatches between electrical and thermal power. The paper also shows that a net-zero energy building may neither be a net-zero exergy building nor a zero-carbon building due to these exergy destructions. • Second Law redefines Net-zero buildings, showing unrecognized root emissions causes. • Exergy destructions are responsible for these root causes. • Unrecognized root emission causes are at least 60% of known sources. • A case study shows that solar prosumers may be upgraded for nearly nearly-zero carbon building. • Net-zero carbon building is not possible for inevitable and irreversible exergy destructions. [ABSTRACT FROM AUTHOR]
- Subjects :
- *CARBON emissions
*HEAT pumps
*ELECTRIC power
*SOLAR energy
*EXERGY
Subjects
Details
- Language :
- English
- ISSN :
- 03605442
- Volume :
- 256
- Database :
- Academic Search Index
- Journal :
- Energy
- Publication Type :
- Academic Journal
- Accession number :
- 158607857
- Full Text :
- https://doi.org/10.1016/j.energy.2022.124442