Calculating a church’s carbon emissions
Compiled from emailed question and answers between Iris Lee and Amy Ross from A Rocha Aotearoa NZ, and Caitlyn Lee, from St Michael’s Anglican Church in Kelburn, with further input from Rev. Tim McKenzie and Matthew Bartlett.
St Michael’s Anglican Church in Kelburn recently had a first go at calculating their church’s carbon emissions. We corresponded with Caitlyn Lee, a parishioner at St Michael’s who worked on the carbon calculation for the church. Caitlyn is also an Architectural Graduate and Living Building Challenge (LBC) Researcher at Tennent Brown Architects.
Why did St Michael's Kelburn decide to do a carbon calculation for the church?
Last year we found the chancel in our neo-Gothic church had failed earthquake standards. Our small 9am service now worships in the timber nave which is safe and the 10:30am service worships in the church hall. This is only a temporary arrangement until our parish raises the funds and decides how to develop our church buildings for our community for the near future and generations to come. A Property Committee has been appointed to oversee these important decisions. A carbon calculation was required as we included it in an online survey for our parish to enable participants to reflect and give informed feedback on the property redevelopment project since many are concerned about climate change and our responsibility as a parish to help reduce our carbon emissions. The results of the survey are summarised on the right.
Which calculator did you use, and why?
When I was approached to perform the carbon calculation I used the Catalyst ACE Carbon Calculator because it was the calculator I was familiar with and had used previously to calculate my firm's carbon footprint in the last financial years. You may read about my firm's carbon calculation journey here. There are many other calculators available, both free and paid. I have heard of another one by EKOS that I would like to learn. Advantages of the Catalyst ACE Carbon Calculator are: it's free, it's easy to navigate particularly if you are familiar with Excel, it's updated regularly and it's tailored to New Zealand.
What sort of information did you need before you could start using the carbon calculator for your church?
I was able to obtain the following input data from Tim McKenzie, our vicar and Matthew Bartlett, our vicar’s warden.
Gas bills
Energy bills
Distance travelled by parishioners to and from church (using the addresses from the parish directory and Google maps)
Engine size of parishioners' vehicles (we had to make assumptions here and used 1.6L as an educated guess of the average engine size)
Volume of mixed waste (estimated from the size of our bins and how often they were emptied)
There are other inputs requested in the calculator worksheet (see below) but in our case these were not applicable. Tim, the vicar, cycles. And church staff do not fly for the purposes of their work.
Taxi or vehicle travel by staff for the purposes of work
Flight travel by staff for the purposes of work
Appliance (fridge, air conditioner etc.) refrigerant code e.g. R134a, R404a etc.
Quantity of refrigerant lost over the year via service records, or, refrigerant capacity of the appliance from the manual
Where did you get the various information from?
Our gas bills were from Nova Energy and energy bills were from Flick. I had to configure them so that the figures could be entered in the right units into the carbon calculator worksheet.
When I calculated the carbon emissions for Tennent Brown Architects, I obtained Air New Zealand flight records for all flights by staff from our Practice Manager. Basically, I asked for receipts, invoices, or records of any sort, whether they were taxi charges via our Practice Manager or personal vehicle engine CC size by speaking to each person on our team – we have less than 20 staff which is manageable.
In whatever form the information came, I got it into the right units for the Catalyst ACE Carbon Calculator. If you are dexterous with data then this is not such a difficult task. I am not necessarily dexterous, sometimes I have a few goes at it and I still run it by someone else, so do not be intimidated. A Rocha is hoping to run a workshop in due course where myself and others can offer support to eco champions who may be finding conversion of units or any other aspect of their carbon calculation difficult.
Was there any particular information that was really hard to get? And what did you have to do to get the info?
We wrote off the one fridge as negligible for the purposes of this survey considering we were pressed for time and unsure whether there were actually service records or a manual for such an old fridge.
However, I do recommend entering all inputs including refrigerants if you are able to. According to Drawdown: The most comprehensive plan ever proposed to reverse global warming, pp. 164-165, number 1 on the drawdown list is refrigerants. That is if we were to tackle this single issue worldwide, it would have the highest impact. While most think of the impact of their flights, we need to educate people about refrigerants as they are potent, unpublicised and ubiquitous. Thankfully there are better refrigerants out there these days and also architects and engineers are thinking of better if not age-old design solutions to heat and cool even commercial buildings. My firm was issuing excerpts from "Drawdown" in a series of blogs, so you can read more about refrigerants here.
Was there anything that you would have done differently?
Having gone through the carbon calculation process once, and having discussed the process with A Rocha, which is a very useful reflection exercise, I think we may need to do some recalculations to include mid-week travel to church activities like home groups, vestry meetings, youth group meetings, evening events etc. Also, we do have other part-time staff members at the church whose vehicular travel we should account for, as well as the vicar’s as he does drive occasionally.
Additional notes: To gather information about distance travelled by parishioners and their mode of transport, churches could do a more in-depth survey with parishioners if time permits. For example, this spreadsheet is used by 360°carbon to collate results from a travel survey done at a church and would allow for more precise data that takes into account those who walk, cycle, use public transports or drive using hybrid or electric cars. More on 360°carbon at the end of this article.
What did the results of the carbon calculator tell you? Was there anything surprising?
The graph shows the month by month St Michael's Anglican Church Kelburn from 1 January 2020 - 31 December 2020 carbon footprint totalling 5.38 tCO2e (tonnes of carbon dioxide equivalents) for the whole year.
5.38 tCO2e sounds about right considering the carbon impact of Tennent Brown Architects for a year was about 24.66 tCO2e, with 45% of that being from flights. The carbon impact of parishioners' travel to and from church was the highest, higher than the carbon impact of electricity use. It was not necessarily surprising, but interesting and informative to see that ratio. As you would expect, electricity use was greater during winter months due to heating.
Did you notice any particular emissions relating to the church lighting set up? Sometimes changes to LEDs from fluorescent lighting can make a difference to overall energy consumption. Some churches have security lights on and timings may be adjusted.
Sensor lights even for indoors are good. I thought we would have switched to LEDs by now; we will need to check whether we are still using any fluorescent lights. One thing to keep in mind is that fluorescent lighting has mercury, and needs to be disposed of carefully.
Additional Notes: The Ministry for the Environment has a four-page info sheet detailing different types of household lamps, benefits of use, as well as safe disposal and clean up of energy saving and mercury containing lamps.
What's next? How will the church use the results of the carbon calculation?
Our church has moved away from gas heating and are currently using heat pumps in the main church building. The gas heating was redundant since heat pumps were installed, so we took the opportunity to disconnect our gas.
Our church is well-loved, and even when parishioners move quite far away, many keep attending here. There is discussion within our church about how we can make it more possible for parishioners to remain living within parish bounds and to build a stronger local community. It's not obligatory that a family or individual lives close to church to attend, but we think parishioners ought to be able to have a choice, and the housing crisis is making this less and less of a choice.
The total emissions for St Michael's Kelburn in 2020 was 5.38 tCO2e. The easy estimation is 1 tree to sequester 1 tonne over its 40-year lifespan, so we would need to plant 6 trees. However, if it takes 5 trees to ensure that at least one lives to 40 years or that their combined sequestration equals one tonne (http://www.carbonify.com/carbon-calculator.htm), we need to plant 5.38 x 5 = 27 trees to account for our emissions for that year. However, the carbon targets we are trying to meet are by 2030 and then by 2050. There is not 40 years of time. To actually have the carbon we emitted in a year sequestered in a shorter time frame we would need to plant more.
Tennent Brown helped the Manawa Karioi Ecological Restoration Project by planting 200 trees in Island Bay. 15 people were able to plant 200 trees in about 3-4 hours. I suggested to my church that we should do the same, just go out and plant 200 trees one afternoon.
I have done the maths here to figure out how many trees we should plant to account for our 2020 emissions in order to have it sequestered by a certain year.
To ensure 5.38 tCO2e is sequestered by...
If we go out and plant 120 this year, we will have 2020's emissions sequestered by 2030 and if we plant 200 trees just a bit more to be sure. We can wipe the sweat off our brow in more ways than one - phew, we worked it out and we will have paid off our carbon debt for 2020 by 2030!
One thought though... we are going to have to plant more trees the closer we get to 2030 or 2050 if we do not go about reducing our yearly carbon emissions. Planting 200 trees this year is a good idea, I mean imagine if this year was 2049, according to the above table, we would have to plant 1076 trees to have it all sequestered by 2050. It's good physical exercise and great for New Zealand biodiversity to be planting. If, however, we cannot heave the parish out there planting trees, and maybe for some of us we physically just cannot plant trees, there's always offsetting (paying someone else to plant your trees in some other part of the world) and people are coming up with innovative ways to offset too such as https://www.carbfix.com/, which does not seem too expensive.
Offsetting is great to deal with the carbon emissions that cannot be avoided and it is very interesting to see how you have considered the timing, nature and amount of tree planting that would be required to offset St. Michaels’ carbon emissions. Goals could also be set to reduce emissions over time.
Finally, the carbon calculation could presumably be repeated annually at around the same time of year, using the same input categories, to track how the church’s carbon footprint changes (hopefully, reduces) over time.
Yes. Definitely. As a church we need to put together an action plan.
It is certainly a good aim to report the figures and try to reduce the per capita figures each year. As well as getting the parish excited about going carbon neutral not just as a parish, but even personally.
-----------------------------
Further Notes:
When calculating a church’s carbon footprint, one of the key questions that you will need to answer is: “What are we going to include?”
This is the “boundary” of your church’s carbon footprint and needs to cover the emissions that are reasonably considered to be “your church’s”. Your church’s emissions are generally the things that you have control over in some way – either directly by, for example, turning off lights, or indirectly by goods and services you choose to purchase.
Once you have decided what is to be included in your footprint, you should continue on the same basis for subsequent years as far as is possible.
Food and drinks served at church were not included in the calculator used in this example, nor the carbon footprint from consumption of goods like stationery and cleaning supplies or services such as church cleaning, gardening services, accounting services etc. The calculator used in this example only asked for waste volumes.
So, it is worth noting that some carbon calculators are more comprehensive than others. If a denominational body were interested in comparing the footprints of different churches in their network, it is worth ensuring that the same calculator is used.
A Rocha Aotearoa NZ is currently in discussion with Climate Stewards, an independent NGO that is part of the network of A Rocha organisations, to customise their church carbon calculator 360°carbon for the NZ context and using NZ emission factors. We hope to have the carbon calculator for churches ready to use in the final quarter of 2022.
Climate Stewards began as an A Rocha climate initiative that enabled people to offset their emissions. Offsetting your carbon footprint with Climate Stewards funds carbon reduction projects (tree planting, cookstoves and water filters) in Ghana, Kenya, Uganda, Nepal, Tanzania and Peru.