This document breaks down our carbon footprint and offsets for 2021. The approach we use is detailed in our inaugural 2020 Carbon Report.

As a quick recap, our approach focuses on:

• Reliably estimating our annual carbon footprint, to serve as a baseline for reduction efforts and to serve as an input to our offsetting efforts;
• Offsetting all of our estimated emissions for 2021; and
• Identifying concrete steps we can take in 2022 to reduce our emissions.

Unfortunately, in 2021 we were unable to reduce our year to year emissions from 2020. The single biggest factor in this was a growth in cloud hosting emissions, although team growth also played a part. These outcomes and plans to address them in 2022 are detailed below.

As always, we welcome feedback from anyone on how we can improve in 2022 and beyond, and conversely would be more than happy to answer any questions to help other small companies like ours take similar steps.

One thing we have done this year is make our estimator spreadsheet publicly available for any business similar to ours who are keen to generate a quick-and-dirty footprint for the same purpose.

Estimating our carbon footprint

We use tCO2e (metric tonnes of carbon dioxide equivalent) to measure our footprint. This keeps our calculations simple and allows us to use a single number for offsets and future comparison.

Wherever possible, we’ve leaned conservative in our estimates (for example, we calculate home office emissions based on full usage during 2021, despite the fact that we weren’t 100% WFH for the entire year).

Offices (10.27 tCO2e)

We have a single co-located office, at The Commons in Cremorne. Since 2019, they have been 100% carbon neutral (one of many reasons we’re located there), and they do a fantastic job of encouraging sustainability within the office.

As for 2020, 2021 saw Disco employees spend the majority of their working hours at home rather than the office. The electricity used to power employee workstations, and the energy used to heat their home at times when they would otherwise be in the office, are attributable to Disco.

We survey employees to find out how their heat and electricity is supplied, then work on the basis of a 40 hour work week, for 45 work weeks per year, to get total electricity and heating emission estimates.

Our number crunching here came out with emissions of 2.29 tCO2e per year for electricity, and 7.98 tCO2e per year for heating, for a total of 10.27 tCO2e per year for our offices.

This number is up 18% from 2020 - a result of a growing team, although we attempted to mitigate this a little by promoting local carbon-neutral energy providers internally. In 2022, we hope to actively drive this number down by continuing this advocacy; we’d also expect to see a reduction in WFH as some employees choose to spend more time in the office.

Equipment lifecycle (6.03 tCO2e)

In addition to the ongoing emission cost of running our workstations, there’s a a lifecycle emission cost associated with the sourcing, manufacture, and shipment of our hardware. These emissions are often much more significant than those generated by ongoing use, so it’s important to factor them into our overall footprint.

We source all of our hardware from Apple, who very handily provide Environmental Reports for each product they manufacture (example).

Our calculated 2021 lifecycle emissions for new purchases in the year were 6.03 tCO2e.

This is down 32% from 2020 - while our team grew and we refreshed a good deal of equipment this year, we’d expect this drop as last year we included embedded emissions for all cumulative hardware purchased up to that point. While there’s not a lot we can do to further reduce these emissions (our tech equipment are the essential tools of our trade), we can continue to work with suppliers who provide transparency around their lifecycle hardware cost.

Cloud hosting (67.66 tCO2e)

Regrettably, our largest single source of emissions last grew 26% in 2021, despite plans at the start of the year to aggressively focus on this element of the business.

As outlined in our 2020 Carbon Report, we use a simple, conservative formula for calculating the carbon footprint of our cloud hosting based on a per-vCPU (0.2987 tCO2e/year), per-GB RAM (0.0747 tCO2e/year) basis. This formula is applied across our primary hosting platforms: Amazon Web Services and Digital Ocean.

Despite successfully moving almost all of our AWS cloud compute into the carbon-neutral US West (Oregon) region, as well as retiring a large number of application servers over the course of the year, our Digital Ocean usage scaled up significantly to support growth in our core product Submarine, and some other applications were migrated there for operational convenience.

While there are suggestions that at least some of Digital Ocean’s infrastructure is carbon-neutral, there’s no official information page on their website or reliable third party sources like The Green Web Foundation confirming this, so to stick with our conservative approach we treat all Digital Ocean hosting as “dirty”.

Using our formula against the average provisioned compute on Digital Ocean and non-US West AWS for the year, our cloud hosting emissions were estimated at 67.66 tCO2e.

The fact that we saw such a large increase in this category is a miss for us in 2021. While there was plenty going on to distract us from our footprint reduction efforts during the year, there were definitely things we could have done to at least maintain the existing footprint rather than growing it.

Looking ahead to the coming year, there are a few key actions we’ll take to improve this category in our 2022 report:

• Engage with Digital Ocean to get a better understanding of their carbon footprint, and to advocate for the more public dissemination of information around their sustainability efforts;
• Ensure all new infrastructure being spun up to support the next iteration of Submarine is deployed to carbon-neutral platforms;
• Where feasible, move existing provisioned compute from non-carbon neutral regions and data centres to green equivalents.

Travel (7.30 tCO2e)

As for 2020, business-related travel during 2021 was extremely limited due to the COVID-19 pandemic. In the normal course of operations, Disco does see employees traveling domestically and internationally for the purposes of company gatherings, conferences, and events.

No flights or hotel stays were taken for company purposes during 2021.

Historically, we have not tracked or offset emissions from ground transport related directly to Disco’s business activities. That transport has been extremely limited in 2021, so we use a very conservative estimate of 1,000 kilometers of rail travel and 500 kilometers of car travel for a total of 0.19 tCO2e.

As for last year, we decided to include a conservative upper bound for personal travel to and from the office in the course of normal business. To get that upper bound, we assumed all employees drove a mid-sized car to and from work five days a week for 20 weeks of the year, at a distance equal to the employee that lives furthest from the office — a pretty generous bound considering most employees walk, ride or use public transport and live closer than 25km to the office.

Plugging these numbers into a calculator gave us 7.11 tCO2e for the year, taking our overall total travel emissions to 7.30 tCO2e. This is pretty much flat from 2020.

Buffer (8.74 tCO2e)

While our estimates this year have been conservative as always, we again include an ~10% buffer to account for miscellaneous emission sources we’ve missed. The worst that can happen is we become carbon negative!

For 2021, that buffer is 8.74 tCO2e (10% of 91.27 tCO2e, rounded down slightly to give us a nice round final total).

Exclusions

As for 2020, there are some things we know we haven’t taken into account, either by choice or because their overall contribution to emission totals are so small we are confident they are covered by our buffer. These known exclusions include:

• Embodied emissions for non-workstation physical items, such as office furniture, merchandise and gifts. These are very minimal for Disco’s operations.
• Emissions from third-party software vendors. We use a large number of third party software services in our business, and we’ve seen some other companies consider their hosting emissions as part of their own footprint. We’ve excluded these from consideration as Disco is likely a very small percentage of those emissions, and we have no way of knowing which hosting providers are in use or whether they are using renewable energy sources or not.
• Banking. Our business accounts are managed by the Commonwealth Bank of Australia, which does not have the best record when it comes to sustainable investment practices. We haven’t managed to find a good resource for estimating the indirect emissions stemming from our deposit accounts, but are keen to explore this further in 2022, either in the form of offsetting these indirect emissions or by moving to a different bank.

Total (100.00 tCO2e)

Summing the above, our total estimated carbon footprint for 2021 is:

• Offices: 10.27 tCO2e
• Equipment lifecycle: 6.03 tCO2e
• Cloud hosting: 67.66 tCO2e
• Travel: 7.30 tCO2e
• Buffer: 8.74 tCO2e

for a total of 100.00 tCO2e.

Offsetting our carbon emissions

This year, we once again chose to work with Pachama, a carbon offset provider focused on carbon capture through forestry projects in Africa and the Americas. Trees are currently the most scalable and efficient way to remove carbon from the atmosphere, and while there is a need for longer-term capture solutions down the road, the project bundles offered by Pachama were a straightforward way for us to offset our emissions.

We purchased carbon credits for 100 tonnes of CO2 from Pachama for a total of USD$2,460.00. We’ve made our certificate available here.

Interestingly, the per-tonne carbon offset price has more than doubled since last year from USD$10.80 to USD$24.60! We haven’t taken the time to dig into the reasons behind this jump over the past 12 months (prevailing economic conditions could certainly play an impact), but it would be good for us to better understand the drivers here.

Looking ahead to 2022

As we plan to grow our team further in 2022, we’ll continue to look for ways to better estimate our emissions and encourage reductions.

Clearly, the highest-impact move we can make is to reduce our cloud hosting footprint, as that category makes up nearly 70% of our total emissions.

Whereas last year we had a number of potential goals for reduction, in 2022 we plan to focus on this single initiative as our primary environmental priority. We hope this focus will help us be more successful in reduction efforts and we can see a really significant impact when it comes to our 2022 report.

Stay tuned!