An exploration of decarbonising Nelson’s long-lived greenhouse gases by 43% by 2030.

This webpage includes:

• Background

• A media release

• An outline explainer with supporting charts

• Caveats

Background

Nelson City Council has a decarbonisation target for the “community” (i.e. everybody - not just Council’s own emissions) of reducing “gross long-lived gases” (basically all CO2 emissions, with no credits for forestry take-up of carbon) by 8.3% every year until 2035. This broadly aligns with the UN’s IPCC goal of reducing emissions by 43% by 2030 in the quest to keep global overheating below 1.5C. (Note the IPCC frames this as giving better than a 50% probability of succeeding - awful odds for averting a catastrophe. )

This page explores how a 43% reduction might be achieved. There is a press release, an explainer, including charts showing Nelson’s regional emissions of long-lived GHG (Figure 1), how they can be reduced (Figure 2), and the different emissions reduction activities that have been computed (Figure 3). Figure 4 shows the calculations in more detail framed around Nelson’s regional “Greenhouse Gas inventory” (an extract is on the table’s left side) and showing emissions from different sectors - see also see note a) below.

The rest of Figure 4 shows how, under our illustrative example, these emissions could reduce progressively until 2030. This calculation involves applying reduction factors tailored to each category and applied to the previous year’s emissions. How the reduction factors are derived is shown in the last table, Figure 5 (colour coding links the various resultant factors to the Annual Reductions table in Figure 4).

The total emissions reduction achieved is the 43.1% shown in red at the bottom right of Figure 4.

Most of the reductions have been achieved at very low cost to Council (refer table of reduction initiatives in Figure 3).

Please refer to the end of this webpage for important caveats.

Media release - A plan for meeting Nelson's climate strategy target   

8 September 2025

Local climate change policy specialists have proposed an action plan for meeting Nelson City Council’s target for reducing Nelson’s carbon emissions. The plan focuses on eliminating traffic congestion on arterial roads as a key part of reducing emissions by about 8% per year. Transport accounts for over 60% of Nelson’s emissions.

The emissions target, adopted by Nelson City Council in July, is in line with international agreements and scientists’ recommendations to limit the worst effects of climate change, which Nelson is already experiencing in the form of more frequent and more severe damaging storms. 

“Leading up to the local body elections, we wanted people to know that Nelson can achieve the targets in the city council’s climate strategy,” said Joanna Santa Barbara, co-chair of the Nelson Tasman Climate Forum and one of the authors of the proposal. “Our plan won’t break the bank and in fact it will make Nelson a more vibrant, livable and healthy city.” 

“There are many benefits of acting to reduce our emissions,” Santa Barbara added. “Our plan would eliminate traffic congestion and cut pollution, bring recognised health benefits, and reduce our spending on petrol and diesel. And it would mean that we would be doing our fair share to address the global climate crisis. We can’t expect others to act if we aren’t willing to act ourselves.”

“Eliminating traffic congestion is a key,” said Lindsay Wood, director of climate consultancy Reslienz and another author of the plan. “This would reduce travel times for businesses, buses and commuters who need to travel at peak times. Emissions will be reduced by having fewer vehicles on the road, but also by eliminating idling in traffic jams, which wastes fuel and causes further emissions.”

“International experience clearly shows that you can’t build your way out of a congestion problem with more roads, because they just fill up again in a few years, bringing even more congestion,” said Peter Olorenshaw, convenor of the Nelson Sustainable Transport Strategy group (Nelsust) and a third author. “You have to address the root causes and provide people with better alternatives so they don’t need to drive everywhere.”

To address congestion, the plan anticipates a charge on vehicles using the main arterial roads at peak times. “This won’t happen overnight,” Wood said, “but it aligns with government thinking.” 

Olorenshaw explained, “The current National-led government has said it will adopt legislation to enable ‘time of use’ road pricing to better match supply and demand. There is a growing consensus across the political spectrum that this is a much better way to manage demand and pay for roads and road maintenance. The people of Nelson should be involved in how this policy is developed and implemented here. This would capture the benefits, seen in other parts of the world, of involving the whole community.”

The plan also identifies other potential measures that could be added to give people a better alternative to driving. For example, Nelson’s bus service could be expanded and priority lanes established to allow buses to bypass other traffic. Metered parking could be expanded to the city fringe to further incentivise people to use the bus, bicycle or rideshare. 

Another possible step could be to simplify council building rules to streamline the partitioning of large houses into two living units. This would allow people to live closer to their workplace and help to address the housing crisis at low cost, without the need for additional infrastructure.

The plan includes detailed calculations of the emissions reduction from each of several actions, giving a total reduction of 43% by 2030, in line with Council’s strategy. (See Figure showing emissions reductions.) The plan builds on current trends in electrification of vehicle fleets and measures that are already included in city council plans and budgets, such as the east-west cycleway across Nelson. Revenue raised from the road charges and the extension of metered parking (if adopted) could help to pay for costs of implementing the action plan.

“This plan is a work in progress and is just one scenario to illustrate how the targets could be met,” said Wood. “We will continue to refine and revise the proposed actions based on community feedback and as new information comes to hand.” 

The proposed plan has been developed by a team from the Nelson Tasman Climate Forum, Nelsust, and the climate strategy consultancy Resilienz.

In last year’s annual survey of residents, Nelson City Council found that 68% of residents said that responding to climate change was “important” or “very important”, but only 36% were satisfied with the council’s response to climate change. Of the actions that residents wanted the council to take to address climate change, the action that received the most support was “leading projects to reduce Nelson community emissions”. 

For more information

Lindsay Wood, Director of Resilienz, ph 021 522 148, email Lindsay@resilienz.co.nz 

Joanna Santa Barbara, Co-chair of Nelson Tasman Climate Forum, ph 022 4590650

Peter Olorenshaw, Convenor, Nelsust, ph 027 628 1686

EXPLAINER

Caveats

a) At the time of writing we only had access to draft inventory figures - these will soon be updated.

b) Adjustments have been made to inventory figures to account for changes between the base year of 2019 and the commencement of this decarbonisation run. The adjustment factors are based on NCC data and can be seen bottom left of the table in Figure 4.

c) The table in Figure 4 displays items from the inventory that are being decarbonised - hence totals in the sector panels (e.g. 203,059 for transport) include items that are not being reduced and so the total is higher than the sum of the figures displayed just above it.

d) While efforts have been made to base these calculations on realistic data, it is an exploration of a possible scenario, and not a firm and fully investigated proposal.