This is a question many people ask but the answer isn’t clearly defined. We will try to shed some light on what a net zero building is.
To understand net zero buildings we need to firstly understand the rationale behind net zero.
What is net zero?
The whole idea behind net zero stems from the concept of decarbonisation. To decarbonise means to ultimately minimise or even better, eliminate emissions of carbon dioxide and green house gases into the atmosphere. To be at a point where we are working at net zero means that we remove as many emissions as we create therefore stopping additional emission levels from further damaging the planet. This understanding should therefore form the basis of what a net zero building should be.
What is the industry definition of a net zero building?
Simply put, for many consultants a net zero building is an all-electric building that does not use gas for heating or hot water. By not using gas in buildings we are able to quickly eliminate carbon emissions – or so we think. The issue with this perspective is that whilst it is straightforward to execute, it ignores the emissions created by electricity production to supply these now fully electric buildings.
So many parts of the building and design industry simply replace the boilers that traditionally heated a building with heat pumps, however, heat pumps use a lot of electricity and our electricity supply still uses a fair amount of carbon, 0.16kg per kWh or electricity, a big improvement from the 0.44kg per kWh that it used to be but still a lot of carbon.
So if we remove the industry shortcomings that have seeped into the accepted practice for net zero buildings currently, lets look at what a net zero building should really be.
What is the REAL definition of a net zero building?
A true net zero building is a building that needs little to no additional energy to run in its day to day intended function. The way this is achieved is by the buildings design and integrated technology; this tech should define how to to reuse heat, regulate cooling, ventilation and so on.
What we really need is a building that uses as little energy as possible. Not a low energy building as we have them already and they still use a lot of energy, what we need is an Ultra Low Energy Building, not a ULEZ but a ULEB!
