Net-zero or real-zero

A statement by Fortescue Mining's Chief Climate Scientist
From Climate Integrity

The net-zero by 2050 target that many countries have adopted sounds wonderful, until you dig into it.  The goal of net-zero is to balance emissions with net withdrawals of greenhouse gases from the atmosphere, in other words to stop atmospheric levels of greenhouse gases (Co2, methane, NOx) from rising.  That's logical, isn't it?  

Only, it hasn't worked out this way.  Polluters have bought "offsets" to "reduce" their net emissions.  But what are these "offsets"?   A village in a poor country promises not to cut down a forest, and the net emissions "saved" by this are bought by an industrial company, which can then claim its own net emissions have "fallen".   Only, when we investigate, we find that the villagers have in fact cleared the forest.  Or an Ozzie farmer promises not to clear some land, which he was not going to clear anyway, and that counts as an "offset".  Or trees will be planted on previously cleared land, and since trees absorb carbon dioxide, this can be monetised as an "offset".  Never mind that at the next bushfire, all the carbon embedded in the trees will be released back into the atmosphere.  

Meanwhile, actual emissions haven't fallen.

When the idea of net-zero was bruited, polluters fell upon it with cries of glee.  They could keep their existing operations unchanged, but still gain kudos by claiming how green they were.  An Ozzie oil company claimed its petrol and diesel were "green" because it bought "offsets" equal to the CO2 that would be produced when the petrol was burned.  An Australian electricity utility claimed its electricity was "zero-carbon" because it bought "offsets".

You get the picture.

The problem is that real withdrawal of CO2 from the atmosphere is expensive — unless you capture the CO2 directly from the flues of coal- or gas-fired power stations, and bury it deep underground, and even that adds  +-$90/MWh to the cost of the electricity produced.  (That's a 2018 costing; it's certainly much higher now.)  If the carbon dioxide produced really is stored in deep caverns, and doesn't leak back into the atmosphere, then this will genuinely reduce atmospheric carbon emissions, and so qualifies as a genuine carbon offset.   And yet, for the cost of adding CCS (carbon capture and storage) to coal/gas power stations, you could have a battery-solar farm at a lower cost per MWh, which can provide carbon-free baseload power. 

Hence the increased interest in real-zero.  Zero actual emissions, not some accounting fudge with pretend reduced emissions.  What a novel idea!

So let's suppose we target real-zero by 2050.  How fast would emissions have to fall each year to get there?  Well, emissions would have to fall by 12% a year, compound.  I don't want to shatter your hopes, but that is not going to happen.  It's true that China's emissions have prolly peaked.  But as for an imminent steep decline?  India's emissions are still rising, even though renewables provided all of the increase in electricity demand last year thanks to a cooler than normal summer.

+-30% of emissions comes from electricity generation, and +-15% from land transport.  If we could stop emissions from these two sectors by 2050, that would translate into a compound annual decline of 2.5%.   This should be easy to achieve.   EVs are heading rapidly towards 100% of car, light and heavy truck and bus sales.   By 2050, the existing ICEV fleets will have been transitioned to EVs.   By 2050, most of the world's electricity grids will be nearing 100% renewables, as wind, solar and battery costs continue to fall.

But a 45% cut in emissions by 2050 is not enough.  The rise in global temperatures is proportional to the level of emissions.  Halving emissions will halve the temperature increase, but recently the rise in temperature has accelerated, from 0.2 C to 0.3C per decade.   We want to cut the decadal rise to 0.1 degrees C, or less, to give us more time to transition to a zero-carbon economy.

Suppose, instead of 2.5% per annum, we were to target 5% per annum?  That would cut emissions by 70% by 2050, reducing the decadal temperature rise to 0.1 C.  In addition to electricity generation and transport, we would need to cut emissions in industry (iron, steel, chemicals, cement), and replace oil and gas heating with heat pumps. 

Even if net-zero was a sensible target, it's 24 years away.  How many of the politicians earnestly assuring us that they really, really mean to reach this fabled land will still be around to explain their failure by then?  We need an annual target.  And I submit that the annual target should be 5%.  2.5% per annum will be easy.  5% will require an effort.  But it will also mean we could limit the increase in global temperatures to 2 degrees C by 2050.

These would be the long-term 2050 targets:

✔️ 100% of electricity from renewables;

✔️ 100% of car, light truck, heavy truck and bus fleets electric;

✔️ All water and space heating via heat pumps, or electric (not oil/gas);

✔️ Steel made via hydrogen/methane/electric arc;

✔️ Electrification of industry;

✔️ A carbon tax on domestic production, and a carbon border tax on imports from countries which do not have a carbon tax.

Is this doable?  Yes, but it will involve standing up to lobbies.  

What about agriculture?  By 2050, by far the biggest percentage of emissions will be from producing meat and dairy and the land clearing that goes with that.  At that point, taking on the agricultural lobbies will be unavoidable.  Maybe we should be starting right now.  You don't need to wait for legislation.  Just stop eating meat.