How will we get to net zero emissions by 2050?

A goal of Net Zero Emissions Economy by 2050 is the number one policy for Green co-leader James Shaw, but Shaw either isn’t sure how to achieve it, or seems unwilling to openly say what he wants – a drastic cut in cow and sheep numbers.

Net Zero Emissions was number one on the Labour-Green C&A agreement.

Sustainable Economy

  1. Adopt and make progress towards the goal of a Net Zero Emissions Economy by 2050,
    with a particular focus on policy development and initiatives in transport and urban form,
    energy and primary industries in accordance with milestones to be set by an independent
    Climate Commission and with a focus on establishing Just Transitions for exposed regions
    and industries.

a. Introduce a Zero Carbon Act and establish an independent Climate Commission
b. All new legislation will have a climate impact assessment analysis.
c.  A comprehensive set of environmental, social and economic sustainability indicators will be developed.
d. A new cross-agency climate change board of public sector CEOs will be established.

It seemed like an idealistic pledge without much of a plan.

But it is still far from certain about how this might be achieved. Shaw is looking for ideas, and points at some, but even they say “how we plug the gap between 95% and 100% in New Zealand isn’t obvious yet.”

Briony Bennett claims “Changing land-use from dairy, sheep and cattle farming to new forests or low-emissions crops and horticulture (growing fruit, vegetables and flowers) is key to achieving carbon neutrality in New Zealand by 2050.”

That seems to be something that Shaw and the Greens are not prepared to come out and push openly.

Bennett has a Masters in Energy Economics and Policy from Sciences Po, Paris. She moved back to New Zealand in late 2017.

Before Christmas, the new climate change minister and Greens’ party leader announced the Government’s intention to pass a Zero Carbon Act, whereby the New Zealand economy would achieve carbon neutrality by 2050. Industry, think-tanks and public sector officials have produced huge volumes of data, modelling, analyses and arguments since then. Within the last few weeks, the Interim Climate Change Commission was announced and the Productivity Commission published a 500-page draft report on the transition to a low-emissions economy. We all want to know what do we need to do to reach net zero.

It seems that Green co-leader James Shaw made the pledge first, and is now looking for ideas on how to achieve it.

This points to Bennett as a Guest Writer at The Spinoff:  NZ has pledged zero carbon by 2050. How on earth can we get there? (abbreviated):


100% renewables

Around 85% of New Zealand’s annual electricity supply is generated from renewable sources. Gas or coal-fired generation is used to meet winter demand peaks and back up supply in low rainfall years. Hydroelectricity constitutes more than half of the national power mix. In a high hydrology scenario, with good seasonal rainfall and snow melt, hydro-power can meet up to 65% of our annual power needs, but dry years present a great challenge and a barrier to reaching 100% renewables.

Under current resource management laws, it is highly unlikely that a new large-scale hydro-power scheme would get built in New Zealand. We could feasibly expand lake storage in current schemes, but not double it, which is what would be required. Further, this would do little to address the main barrier to reaching a 100% renewable power supply, which is our dry-year risk.

Wind power

At an emissions price of $75 or greater it will be economic to build enough wind farms to reach about 95% renewables in New Zealand, according to Concept Consulting.

Today, a significant number of wind projects have actually been consented, over 2.5GW according to the NZ Wind Energy Association, but project developers are waiting for prices to rise before starting construction. However, wind power cannot ensure our power supply is 100% renewable in a dry year since it is not guaranteed to be available during winter peaks when demand is at its highest.

Grid-scale or rooftop solar exacerbates the seasonal storage challenge as it only generates during periods of low demand and has a much higher output during the summer. We need power sources that are as flexible as coal and gas-fired power plants to meet seasonal demand.

Big batteries

Grid-scale battery storage projects have been making headlines around the world. Tesla installed a massive battery in South Australia after Elon Musk made a promise to do it in 100 days or for free on Twitter. Bloomberg New Energy Finance’s (BNEF) lithium-ion battery price index shows a fall from US$1,000 per kWh in 2010 to US$209 per kWh in 2017.

Nevertheless, this technology cannot economically provide seasonal or dry-year power storage of the scale required at present. They just do not pack as much punch as hydro storage.

…this suggests we need 400 million batteries, or over 250 Tesla Powerwalls per household. Even at a discounted price of just US$2000 this would require an investment of over US$500,000 per household or US$800 trillion in total. More than four times our current GDP. We could spend that money more wisely to reduce our greenhouse gas emissions.

Car culture

Power sector emissions have declined 13% since 1990 and make up less than 10% of total emissions. In the same period, transport emissions rose 70% and constitute 20% to New Zealand’s emissions. Car ownership reached its highest level ever last year, at 774 light vehicles for every 1,000 New Zealanders.

This is the beast we must tackle. Electrification is the key pathway with existing technology to cut the majority of transport emissions. To charge electric passenger vehicles and e-buses, electrify trains, and reduce fossil fuel usage for heating, a reliable and affordable electricity supply is crucial.

Power outlook

With more wind, batteries and additional geothermal power plants, it is technically feasible to reach the 100% renewables target when we have average or high rainfall. This would be achieved at great expense and put significant upwards pressure on power prices. Other flexible technologies, such as demand response or renewable power-to-gas, hold great potential to help New Zealand reach 100% renewables. Biomass or tidal power generation could emerge as affordable means to generate electricity in New Zealand in the next few decades.

Solar and wind offer a comparatively low-cost pathway to reduce emissions in most countries that currently have a high share of coal and gas-fired generation, but how we plug the gap between 95% and 100% in New Zealand isn’t obvious yet.

Planting trees

All pathways to net zero, require forestry to play a major role. Afforestation is like a credit card, buying us time to develop alternative technologies to replace current agricultural and industrial processes. A methane vaccine for animals or other biological inhibitors that can be mixed with their feed are being researched, but these technologies remain unproven. Selective breeding, though it can take decades, will also continue reduce the amount of methane produced per animal.

Farming

The New Zealand Emissions Trading Scheme (ETS) is our main tool for encouraging decarbonisation. The scheme requires emitters to pay for each tonne of carbon dioxide or other greenhouse gas produced – this is called an emissions unit. Farmers are currently exempt from participating in the ETS, which covers energy, waste and industry. To achieve net zero this will have to change since agriculture contributes over half of our emissions. To ensure a gradual transition for farmers, they should receive free emissions units upfront and have trading at the full emissions price phased in over time.

Changing land-use from dairy, sheep and cattle farming to new forests or low-emissions crops and horticulture (growing fruit, vegetables and flowers) is key to achieving carbon neutrality in New Zealand by 2050.

This implies that fewer sheep and cattle will be farmed in the future. Reducing, though perhaps not eliminating, dairy and meat exports raises important questions about food production. The carbon footprint associated with a diet rich in animal protein is an issue that is likely to loom larger in public debate.

There are few affordable means to cut emissions from pastoral and dairy farming without reducing herd populations at present.

If all sectors are covered by the Emissions Trading Scheme, businesses that reduce their emissions will be rewarded and pay for fewer emissions units. It is the main tool we have to encourage the changes and innovation required in all sectors to dramatically cut our emissions and reach net zero by 2050 in New Zealand.


So Bennett largely explains that it will be difficult to attain 100% renewable power – and she promotes electric vehicles as a way of reducing fossil fuel emissions, but this would require substantially more electricity.

She is basically saying planting a lot of trees is one way of getting to zero net emissions, but that’s only a short term solution,

Her primary suggestion is effectively applying the Emissions Trading Scheme to farming to drastically force cow and sheep numbers down.

Is this what Shaw and the Greens want? If so they should come out and say it.

7 Comments

  1. Alan Wilkinson

     /  May 30, 2018

    Fake accounting and cheating is the usual political way to achieve the impractical. Let’s hope that happens here to avoid the catastrophe of actually implementing the policy.

  2. David

     /  May 30, 2018

    A consistent thing with the left is they never have a plan, they scream a headline, virtue signal an end goal but then literally dont have the grit, determination, intelligence or even a first clue on how to get there.
    Closing the gap writ large.

  3. Alan Wilkinson

     /  May 30, 2018

    4.9C outside and not even June. Roll on global warming.

    • David

       /  May 30, 2018

      4.9 is tropical and looks like an early start to the ski season too

      • Alan Wilkinson

         /  May 30, 2018

        Down to 4.2C now. Getting colder. Time to walk the dogs if they are brave enough.

    • PDB

       /  May 30, 2018

      1.0C here in the Waikato at present – going to be a lovely day though.

      • Kitty Catkin

         /  May 30, 2018

        Eek.

        There was a bit of frost where I am (Waikato) but it was very little. Bloody cold until the sun came out, then it was quite balmy. Time to swap all the cotton blankets for winter ones, which is often a signal for the cold nights to suddenly warm up again so that we cook.

        I wonder if Mr Shaw uses those lovely light, warm blankies or the old kind ? I have just bought a new ‘mink’ one in a Warehouse sale. Were wool ones always the equivalent price to what they are now ? Surely not.