What do they all mean, and how are they different?
All of these terms are referring to the same thing:
A reduction in the amount of greenhouse gas emissions produced by an organisation to zero or below zero.
It's the how that's different.
Almost every business on the planet generates emissions within its operations and across its supply chain. The first step is mapping and measuring these emissions. The next step is to directly reduce emissions as much as possible by investing in more efficient equipment, changing employee behaviours, or generating renewable energy. Businesses can then invest in offsets that reduce emissions elsewhere in the world to compensate for the hard to reduce emissions that are generated in the operation.
By offsetting all other emissions that the operation produces, businesses can claim to be carbon neutral. This can be done adhering to the carbon neutral PAS 2060 standard, ensuring an emissions inventory is built and managed, and further reduction initiatives are planned for the future. This is a great first step for businesses to take.
By offsetting all emissions and then some more, businesses can claim to be carbon negative or climate positive. Offsets can come in many different forms, namely reforestation projects, renewable energy, and community based projects. Businesses are now investing further in a wider range of projects that go beyond their own carbon footprint, to generate positive change and negative emissions.
Some businesses that have set future carbon negative targets, are looking to do this by directly reducing their emissions below 0. This will require huge direct investment in zero emission supply chains as well as carbon removal projects within the operational boundaries. An example of this would be investing in Direct Air Capture technology that directly removes carbon dioxide particles form the atmosphere.
Businesses cannot claim to be net zero until all emissions from the operation are directly removed or reduced as much as possible before offsetting the extremely hard to remove emissions (like shipping and air travel in the UK government's plan).
It is important to emphasise that the transition to net zero is a global effort. Doing everything we can to reduce emissions now, either directly or indirectly, will give us every chance of staying within the 1.5 degree target.