Transport and CO2 emissions

It seems timely to talk a bit about carbon dioxide emissions, as the government is currently undertaking consultation on what New Zealand’s 2020 target should be in terms of reducing our CO2 emissions when compared to 1990 levels. There has been a big push for a dramatic 40% reduction target, as that is what is considered necessary to avoid the worst effects of climate change, although it is likely the government is going to end up on something a bit more modest. While having a more modest target would be a disappointment, I think in some ways a more critical question is “how are we going to achieve any reduction?”

Since 1990 New Zealand’s gross CO2 emissions (that is, everything we pump out) have increased quite significantly. However, due to a lot of tree planting in the 1990s our net emissions (gross emissions minus the amount of CO2 trees can suck out of the atmosphere) is about level. However, to actually decrease our net emissions by anything substantial in the longer-term, it will be necessary to reduce our gross emissions. And this is where things get tricky. New Zealand’s CO2 emissions largely come from three sources: agriculture, power generation and transport. It is notoriously difficult to reduce CO2 emissions from agriculture without reducing food production – certainly something we wouldn’t want in a world with a growing population. Steps will have to be taken to find ways to reduce agricultural emissions, but they are a while away yet. Regarding power generation, while we can certainly do more to reduce these emissions by investing in renewable energy generation and taking pressure off our backup coal and gas stations, we actually do pretty well when comparing with other countries internationally. This means that our ability to significantly reduce emissions from power generation are somewhat limited (as already 70% or so of our electricity is renewably generated).

Which leaves transport. Over the past 18 years emissions from transport have gone horribly in the wrong direction. According to the Ministry of Economic Development:

“Emissions from national transport continue to account for the largest share of total energy emissions. National transport emissions have grown by 64% since 1990 at an average growth rate of 2.8% per annum, although this has slowed in recent years. Emissions from road transport account for the largest share of national transport emissions at 90%. This represents 38% of the total energy carbon dioxide equivalent emissions for New Zealand.”

So transport is a significant problem. But short of completely overhauling our entire transport system, what can we actually do about this? Well, trends in the last year provide some interesting insights into that:

Road transport emissions, however, dropped in 2008 for the first time since the energy greenhouse gas emissions series began. This is likely to be due to high petrol and diesel prices in 2008 and the beginning of the global recession.

While obviously we don’t want to encourage recessions as ways in which to reduce transport-sector CO2 emissions, the telling aspect is that to reduce our emissions we need to get cars off the road, and that pricing (in the form of higher fuel prices) is a way in which to achieve this. Now obviously it would be enormously unfair to simply price people off the road without providing them with alternatives – which is why it is so essential for public transport to be heavily invested in over the next few years in particular. We will end up with some sort of emissions trading scheme to provide incentives to reduce our emissions and encourage planting forestry. This scheme will add to the price of petrol, potentially quite significantly in the longer term. Therefore, we need to provide people with effective alternatives to driving so that we can reduce our transport sector emissions without having enormous social inequity outcomes of people simply not being able to afford to undertake their daily activities.

Of course this goes against absolutely everything Steven Joyce has said about transport since he became the Minister. I wonder if he ever does talk to Nick Smith, the Minister for Climate Change Issues?

One particularly interesting aspect of the transport sector emissions is the significant contribution that diesel makes – even though the number of petrol cars on the road is hugely greater than the number of trucks. This is evident in the picture below:

Just one more reason to focus on shifting freight to rail, which is far more efficient, rather than allowing even bigger trucks on our roads.

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