In an age where consumers are growing more environmentally-conscious, it is becoming more common for organisations to make pledges about sustainability initiatives and reducing their carbon footprint. In a bid to help consumers better understand some of the terminology used in companies marketing efforts, and to guide organisations to understand the terms they are using, we have analysed some of the popular key phrases and provided a definition of what they actually stand for: –

  • Carbon positive: how organisations describe climate positive and carbon negative. It’s mainly a marketing term, it’s not quantifiable nor scientific. We recommend avoiding this terminology wherever possible.
  • Zero Carbon emissions (in buildings): the carbon emissions created by the regulated energy use of a building, are zero. DER (Dwelling Emission Rate) is Zero or a 100% improvement over part L (regulated refers to fixed services: Lighting, HVAC, HW and LZC technology).
  • Net-Zero Carbon emissions (in buildings): the carbon emissions created by both regulated and un-regulated (occupancy use like laptops, washing machines, kettle) energy use within a building approximately 140% improvement over part L.
  • Net Zero emissions: balanced the whole amount of greenhouse gas (GHG) to zero, consisting of CO2e (carbon dioxide equivalents to include: CO2 N2O CH4 HFCs PFCs SF6), and the amount removed from the atmosphere.
  • Net Zero in Operation: demonstrated through analysis of operational energy data, that the target EUI (Energy Utilization Index) has been achieved. We would carry out a Carbon Footprint study to demonstrate this, often for larger organisations with many buildings and processes.
  • Climate positive/Carbon negative: activity that goes beyond achieving net-zero carbon emissions to create an environmental benefit by removing additional carbon dioxide from the atmosphere.
  • Carbon Neutral: a balance between emitting carbon and absorbing carbon from the atmosphere in carbon sinks.

We are a leading energy and sustainability consultancy, providing professional services for construction projects throughout the UK. To discuss Carbon Improvement and Part L Compliance needs, please don’t hesitate to contact us on 01275 846995 or by email at

Cook Brown Energy is part of Hickton Group, Championing Quality, Compliance, Audit and Sustainability in the built environment.  Please visit our website to find more information about Building Control, Quality Site Inspections, Energy & Sustainability, Gas and Electrical Safety Management or Gas Auditing and Consultancy services.