Net-zero.  It's a term often communicated when it comes our current climate situation.  But what does net-zero mean?  Does it mean if achieved, the job is done, the world is fixed, and we can go back to when we didn't have to worry about this climate stuff?

        

No.  Far from it.

        

Net-zero is not the end goal.  It is a milestone on the path to the end goal - which is a decarbonized energy mix.  The milestone is noteworthy.  Commendable.  Desirable.  However...it is not the end goal.

Miriam-Webster defines net-zero to mean “resulting in neither a surplus nor a deficit of something specified when gains and losses are added together".  In the climate space, we are talking primarily about carbon dioxide (CO2).  So for every unit of CO2 generated, the same amount is removed somewhere else.

How much CO2 are we talking about?  A lot.  Tons.  Billions of tons.  Every year.  In 2021, the world emitted 37 billion tons of C02.  Of that, the US emitted 15% - second only to China which emitted 27%.

This net-zero balance is achieved by a number of ways.  First and foremost, we can stop burning the fossil fuels generating the CO2 in the first place.  However, we can't.  While solar and wind power is displacing coal as a source for electricity, 60% of the US electricity in 2021 came from fossil fuels - primarily from natural gas.  

Interestingly, we have the pieces needed to do away of fossil fuel generated electricity.  We have the solar panels.  We have the wind turbines.  We have a way of transporting the electricity to homes.  However, we don't have the amount of these pieces to generate the needed amount of electricity - yet.  At the moment, there are two limiting obstacles holding us back.  One is the electricity storage to deal with solar and wind's intermittency issue.  The second is the permit process that puts the solar panels, wind turbines, and transmission lines in place.  Both of these obstacles can and will be overcome.   We are just not there - yet.

So, if we can't flip a switch and stop burning fossil fuels to generate electricity that in turn, emits billions of tons of CO2 every year, how do we get to net-zero?

One way is by removing CO2 as it is being produced.  For example, scrubbers at coal plants remove the CO2 before it leaves the smoke stacks.  Another way is through carbon offsets.  This is where a reduction or removal of emitted CO2 is made in order to compensate for emissions made elsewhere.  For example,  a business can participate in a forest restoration project and in return, the business can emit CO2 in some proportion to the CO2 captured by the restored forest. 

The last way I want to point out is through carbon credits.  This is where a transferrable financial instrument, certified by a government agency or independent certification body,  representing a unit of emission reduction, is bought or sold.  In other words, there is a marketplace, like the stock market, where carbon credits are secured and traded.

Each of these ways encourage the reduction of CO2 contributions to the carbon cycle and therefore, achieving net-zero, but...

What about the CO2 previously emitted?  Do we need to do something about that?

Yes, we do.  

Let's go back to the fundamentals associated with our climate situation - the carbon cycle.  The cumulative amount of CO2 emitted over time is beyond staggering.  Think about it.  Billions of tons emitted EVERY year.  The impact from all that CO2 is measured in a concentration unit called parts per million (ppm).  A graph  from the National Oceanic and Atmospheric Administration (NOAA)  shows the impact of that staggering amount by the steep steady increase of CO2 ppm in the atmosphere over time.  

So yes, we must take care of the CO2 previously emitted in the atmosphere.  Therefore, in the end, getting to net-zero is not the end game.  It is a milestone that must be met.  A milestone on the road to the real goal we need to achieve  - a decarbonized energy mix.