Guest Post by Willis Eschenbach

After reading some information at Friends of Science, I got to thinking about how impossible it will be for us to do what so many people are demanding that we do. This is to go to zero CO2 emissions by 2050 by getting off of fossil fuels.

So let’s take a look at the size of the problem. People generally have little idea just how much energy we get from fossil fuels. Figure 1 shows the global annual total and fossil energy consumption from 1880 to 2019, and extensions of both trends to the year 2050. I note that my rough estimate of 2050 total annual energy consumption (241 petawatt-hrs/year) is quite close to the World Energy Organization’s business-as-usual 2050 estimate of 244 PWhr/yr.

Figure 1. Primary energy consumption, 1880-2019 and extrapolation to 2050. A “petawatt-hour” is 1015 watt-hours

So if we are going to zero emissions by 2050, we will need to replace about 193 petawatt-hours (1015 watt-hours) of fossil fuel energy per year. Since there are 8,766 hours in a year, we need to build and install about 193 PWhrs/year divided by 8766 hrs/year ≈ 22 terawatts (TW, or 1012 watts) of energy generating capacity.

Starting from today, January 25, 2021, there are 10,568 days until January 1, 2050. So we need to install, test, commission, and add to the grid about 22 TW / 10568 days ≈ 2.1 gigawatts/day (GW/day, or 109 watts/day) of generating capacity each and every day from now until 2050.

We can do that in a couple of ways. We could go all nuclear. In that case, we’d need to build, commission, and bring on-line a brand-new 2.1 GW nuclear power plant every single day from now until 2050. Easy, right? …

Don’t like nukes? Well, we could use wind power. Now, the wind doesn’t blow all the time. Typical wind “capacity factor”, the percentage of actual energy generated compared to the nameplate capacity, is about 35%. So we’d have to build, install, commission and bring online just under 3,000 medium-sized (2 megawatt, MW = 106 watts) wind turbines every single day from now until 2050. No problemo, right? …

Don’t like wind? Well, we could use solar. Actual delivery from solar panels on a 24/7/365 basis is on the order of 2.75 watts per square metre depending on location. So we’d have to cover ≈ 290 square miles (760 square kilometres) with solar panels, wire them up, test them, and connect them to the grid every single day from now until 2050. Child’s play, right? …

Of course, if we go with wind or solar, they are highly intermittent sources. So we’d still need somewhere between 50% – 90% of the total generating capacity in nuclear, for the all-too-frequent times when the sun isn’t shining and the wind isn’t blowing.

To summarize: to get the world to zero emissions by 2050, our options are to build, commission, and bring on-line either:

 One 2.1 gigawatt (GW, 109 watts) nuclear power plant each and every day until 2050, OR

 3000 two-megawatt (MW, 106 watts) wind turbines each and every day until 2050 plus a 2.1 GW nuclear power plant every day and a half until 2050, OR

 290 square miles (760 square kilometres) of solar panels each and every day until 2050 plus a 2.1 GW nuclear power plant every day and a half until 2050.

I sincerely hope that everyone can see that any of those alternatives are not just impossible. They are pie-in-the-sky, flying unicorns, bull-goose looney impossible.

Finally, the US consumes about one-sixth of the total global fossil energy. So for the US to get to zero fossil fuel by 2050, just divide all the above figures by six … and they are still flying unicorn, bull-goose looney impossible. 

Math. Don’t leave home without it.

My very best wishes to everyone, stay safe in these parlous times,


PS—As always, to avoid misunderstandings I request that when you comment, you quote the exact words that you are discussing so we can all be clear about who and what you are referring to.

Technical Note: These figures are conservative because they do not include the energy required to build the reactors, wind turbines, or solar panels. This is relatively small per GW of generation for nuclear reactors but is much larger for wind and solar.

They also don’t include the fact that wind turbines have about a 20-year lifespan, so after 20 years we’ll have to double the turbine construction per day. And with solar the lifespan is about 25 years, so for the last five years, we’ll have to double the solar construction per day. And then we will have to decommission and dispose of hundreds of thousands of wind turbines and square miles of solar panels …

The figures also don’t include the fact that if we go to an all-electric economy we will have to completely revamp, extend, and upgrade our existing electrical grid, which will require a huge investment of time, money, and energy.

They also don’t include the cost. The nuclear plants alone will cost on the order of US$170 trillion at current prices. And wind or solar plus 75% nuclear will be on the order of US275 trillion, plus decomissioning and disposal costs for wind turbines and solar panels.

So it is even more impossible … speaking of which, is it possible to be more impossible?

Because if it is possible … this is it.

via Watts Up With That?

January 27, 2021 at 12:30PM