Carbon neutral building

Low-carbon buildings are buildings designed and constructed to release very little or no carbon at all during their lifetime.

Buildings alone are responsible for 38% of all human GHG emissions (20% residential, 18% commercial). It is the industrial sector which contributes the most to global warming.

But according to the Intergovernmental Panel on Climate Change (IPCC), it is also the sector which presents the most cost effective opportunities for GHG reductions.

Low-carbon buildings (LCB) are buildings which are specifically engineered with GHG reduction in mind. So by definition, a LCB is a building which emits significantly less GHG than regular buildings.

There is no emissions threshold under which a building would qualify as a LCB. But to be genuinely “Climate Change neutral”, a LCB would have to achieve at least 80% GHG reduction compared to traditional buildings. According to the Stern Review on the Economics of Climate Change, our emissions would have to be reduced by 80% compared to current levels in order not to exceed the Earth’s natural capacity to remove GHG from the atmosphere. By comparison, a regular building releases about 5,000 kgCO2e/m2 during its entire lifetime (though it varies a lot, depending on the project type and where it is located).

GHGs are released in the atmosphere during each stage of a building's life:

GHG reduction calculations should consider all stages of the building life: construction (incl. renovation and deconstruction) and operation.

GHG emissions associated with buildings construction are mainly coming from:

The construction, renovation, and deconstruction of a typical building is on average responsible for the emissions of 1,000-1,500 kgCO2e/m2 (around 500 kgCO2e/m2 for construction only).

Strategies adopted by LCB to reduce GHG emissions during construction include:

GHG emissions associated with buildings operation are mainly coming from:

Fossil fuels include natural gas and propane.

Depending on the region where the building is located and the building energy mix, operation emissions can vary from 0 to over 100 kgCO2e/m2 per year.

LCB usually achieve less than 10 kgCO2e/m2 per year.

Strategies adopted by LCB to reduce GHG emissions during operation include:

Renewable energy sources include:

There are three main sources of indirect GHG reductions available for buildings:

These GHG reductions can be used by building owners to offset the emissions which can not be reduced otherwise or to achieve specific GHG target, for example “carbon neutrality”.

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Wikipedia