Some things you just can’t take back. Like that time I cut my own bangs before school picture day. Or split my pants tripping and falling into home plate at softball. And that other time when I emitted a ton of carbon at that last event I went to.

Carbon offsets are an oft-used tool in the sustainable event toolkit. Organizers cling to them as a way to be accountable for event greenhouse gas emissions that can’t be avoided. What they can’t do, however, is reduce or “take back” your actual event emissions. So while they are, in some respects, a way of saying “sorry for my footprint”, they are a very distant and poor second to steps that reduce event emissions.

So what does an offset do then?

Carbon offsets allow you to take responsibility for emissions you opt to not reduce or can’t prevent. When you burn fossil fuels to travel, or your event uses energy to power your venue, polluting emissions are added to the atmosphere. These emissions contribute to climate change, which has wide-spread and significant impacts. While an offset does not allow you to reverse this process, by purchasing an offset you get “credit” for helping avoid equivalent emissions in future.

So is an offset good or bad?

While offsets are not a replacement for real efforts to reduce energy use, these credits may allow you to do a variety of things that help the environment. Revenue from the sale of offsets can be used to plant trees in deforested areas, provide safe drinking water to families, or develop renewable energy alternatives, like solar farms. Funding may also support energy efficiency programs, such as improvements to building lighting and heating systems.

While that might sound good, the validity of offsets is hotly contested. Critics point out that many offset programs lack the scientific legitimacy and long-term study necessary to substantiate net emissions reduction. They also argue offsets give us false reassurance we are helping solve a problem while enabling us to avoid or delay steps necessary for more meaningful and urgent climate action.

For these reasons, be warned: Offsets, and particularly offsets in the absence of meaningful reduction, leave events at risk of greenwashing.

How much do they cost?

Prices for offsets can vary anywhere from $3  to $25 per ton, depending on your provider. The amount of emissions from your event varies depending on the type of event you have, how long it is and the distance traveled by attendees. One ton of carbon emissions per event participant is a reasonable footprint to expect for a 3-day national conference. You can ask your offset provider to perform a more accurate calculation for you using actual registration information. Carbon offsets can be paid by the organizer, attendees or a sponsor.

How to find an offset provider?

A simple web search will turn up many different kinds of offset providers. If you plan events for a larger company or organization, ask your purchasing or corporate citizenship office if you already have a carbon offset partner. If you don’t,  consider treating an offset provider as you would any event vendor. Prepare a request for proposals that researches their programs, credentials, references and pricing.  Remember, pricing can be a reflection of the quality of offset you’re buying so don’t go by price alone. Asking if projects offered are additional, permanent, verified and meeting an external standard is important.

Where can I learn more?

• • Purchasing carbon offsets: A guide for Canadian consumers, businesses and organizations (PDF)

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