Greenhouse gas emissions occur at events through the direct operational impacts such as power provision, and through transport of people and equipments. GHGs are also caused upstream and downstream of the event; embedded GHGs in the products used, and through waste disposal and treatment.
The event-related GHGs that could be measured are almost endless. Events could measure those GHGs which are either directly created by them or those which are created because of the event’s activities, purchasing and logistics.
But just because particular GHG emissions have occurred and theoretically could be measured, it doesn't necessarily mean they should be measured. What should be measured (deemed 'material') and how to decide what you scope in or out is the subject of the next article.
For now, let's consider what could be measured.
What's the Scope?
You may have heard of Scope 1, Scope 2 and Scope 3 emissions. GHGs have been categorised as such, as either direct and indirect, by the GHG Protocol (www.ghgprotocol.org). Direct emissions are those that are from sources that are under the direct ownership or control of the event/organisation. Indirect are those that occur as a consequence of the event's activities.
The GHGs that are very likely to be under the direct control or ownership of the event or organisation, when producing an event are listed below. Some of these will be quite straight forward to collect data on, and others could be quite problematic. We'll discuss how to collect measurement data in future articles.
- fuel used in mobile power generators
- bottled and mains gas used by on-site event venue kitchens or temporary on-site caterers and food traders
- gas or oil used for venue heating
- fuel used in site plant and equipment
- fuel used in vehicles used for event production purposes
The primary source of Scope 2 (indirect) GHG emissions are mains/grid electricity supply. This is because the GHGs are created at another source (the power plant), but the electricity is used by the event. If relevant, some venues may have 'district heating and cooling', and if this is the case, then the GHGs from this could be included in the event’s GHG inventory.
Scope 3 is 'other indirect' GHG emissions. This is where things get a little more difficult to decide on what to include or exclude. Possible ‘other indirect’ GHG emissions which seem straight forward to include, as they will have only occurred due to the event, are:
- transport impacts of employees (including all paid contractors, talent, crew)
- hotel nights for event production (crew, talent, staff, contractors)
- freight impact of infrastructure, equipment, goods and services required by the event
- hired transportation used offsite (shuttle buses, taxis, limos, boats, aircraft)
And then going deeper, there is a case to argue that the following event production-related GHG emissions could be included in the tally:
- GHG emissions embodied in the products and materials purchased by the event
- transport of products and equipment to the event
- energy used or GHG emissions created in processing waste (liquid & solid)
- transport of waste (liquid & solid)
- energy and transport to produce and supply water to the event
Over and above the GHG emissions that have been created because of the actual production of the event, we have the big elephant in the room, and that is the impacts of the actual event attendees, namely:
- attendee travel (the single biggest GHG contributor for many events)
- attendee hotel nights
This article won't go through the details of how to capture the data necessary to measure and report the GHGs from event activities. In brief however, you will be capturing data on the litres, gallons, kg, megajoules, or kWh which have occurred from the various activities. These are then converted to kg of GHGs by applying an ‘emissions factor’ (kg of GHGs per unit of measurement). This is usually in the form of an 'equivalent' measure of carbon dioxide, which is expressed at 'CO2e'.
As the scope of GHG inclusions could be considerably different from one event to another, it is difficult to report in a way that has any comparative meaning.
Simply announcing your event has produced X tonnes of GHGs isn’t going to cut it. You need context to have any real meaning. Even more so if you plan on offsetting those emissions and claiming carbon neutrality.
A great way to express your GHG impacts is to do it in terms of energy intensity. This brings the GHG emissions from various sources back to common figures. For example the GHGs from mains and mobile electricity supply, per person or per square metre of activated venue space.
These figures can then be used for comparisons with other events. Examples of energy intensity comparisons include:
- Event power: total kg CO2e from electricity provision, per person per day
- Event Travel: average kg CO2e per passenger km
- Total event GHG intensity: total kg CO2e per person
 carbon dioxide equivalent – put in an explanation