The professional environment industry is gearing up for its annual celebration of Earth Day. Earth Day, for those who are too young to remember, began, arguably officially, on April 22 1970. It was conceived in a flash of inspiration by a U.S. senator during a flight on a kerosene-powered airplane. In spite of that irony (kerosene is, on an energy unit basis, more carbon-emission-intensive than gasoline), and the fact that American petroleum use skyrocketed after 1970, Earth Day has attained an enviable level of popularity. Robert Stone did an excellent documentary on it; it is worth watching.

The famous carbon dioxide, or CO2, molecule. Earth Day should be about CO2, and about how to reduce its emissions into our atmosphere. All efforts and policies aimed at reducing CO2 should be firmly based on amounts of CO2 now and reduction targets. This means we must all become familiar with “CO2 currency,” i.e., the amounts of CO2 that go with our daily activities. This information is available in Ontario, and is given in Tables 1 and 2 in the left-hand sidebar of this blog.
Unfortunately, Earth Day’s visibility has not translated into meaningful results. The website of the Earth Day Network, which is a collection of like-minded organizations, features a slider starting off with The Face of Climate Change, then Environmental Education. Well, climate change is about reducing anthropogenic emissions of carbon dioxide (CO2), the principal anthropogenic greenhouse gas. How many people are aware of the amount of CO2 that goes with their daily activities?
The answer is, sadly, very few. The emphasis in environmental education has been on ways to reduce carbon, and the ways that have been most heavily promoted are to use more wind and solar energy. These aspects of environmental education have been totally successful: in every conversation I have with environmentally minded people, wind and solar figure prominently and favourably.
But are wind and solar effective ways to reduce anthropogenic CO2 emissions? Bear in mind that their envisioned uses are overwhelmingly for electric power generation. The answer is absolutely not. The wind does not blow in a way that makes it viable as a source of grid power, and the earth’s rotation makes solar unavailable for a very large part of each day.
That is why I developed the carbon counter featured in Tables 1 and 2 in the left-hand sidebar on this blog. As you can see, solar is not even reflected in the tables: though it has received top billing in mediated public discussions on climate change, the amount of solar energy feeding the Ontario grid is simply too small to mention.
As for wind, its average capacity factor—that is, the percentage of the year in which all wind turbines are producing electricity at their rated capacity—is in the neighborhood of 30 percent. That means that most of the time, wind turbines are collectively not producing power at or near capacity.
Wind and solar are simply not viable energy sources for an electricity grid.
Ironically, and this is a huge irony, the shortcomings of solar energy led to the discovery of an energy source that is totally viable, and that does not produce any CO2. Henri Becquerel in 1896 tried to find out if there was any connection between the X-rays recently discovered by Roentgen and natural phosphorescence. He noticed that uranium salts next to a photographic plate in his Paris lab produced fogging on the plate, but assumed the phosphorescence from the salts had been stimulated by sunlight. He set up an experiment to prove this, and waited for the next sunny day. But Paris remained socked in and overcast. Becquerel put the salts and plate in his desk drawer. When the weather cleared and he fetched the sample to try his experiment, he noticed a clear image on the photographic plate. He reported in his diary:
I am now convinced that uranium salts produce invisible radiation, even when they have been kept in the dark. They do not need to be exposed to sunlight to produce this effect…. I have kept uranium crystals in the dark for 160 hours. There is no sign of any decrease in the intensity of the radiation which they produce.
He had discovered radioactivity, which is the energy and particles released by certain types of atoms as they undergo spontaneous changes in their nuclei. The basis for quantifying the energy locked in the atomic nucleus, which Becquerel noted (without at that time knowing anything about the atomic nucleus) was capable of producing rays for 160 hours without interruption or external stimulation, would be stunningly formulated in 1905, when Einstein published his Special Theory of Relativity and its famous equation, E=mc2.
Becquerel’s astounding discovery happened when it did because solar energy is so unreliable. Short decades later, uranium fission was discovered, and within decades of that discovery electric grids in the United States, Canada, and other countries were being fed with nuclear energy.
Returning to Tables 1 and 2, you will notice that nuclear is by far Ontario’s biggest source of electricity. It comes with zero emissions of CO2, which is why Ontario’s grid-level carbon intensity per kilowatt-hour (CIPK) was at 10:00 a.m. on Wednesday April 12 only 144.9 grams. Without nuclear, Ontario’s CIPK at that time would have been 423.5.
The CIPK is the fundamental number in clean electricity. If you know the CIPK of your grid, you can measure with precision how much CO2 accompanies every kilowatt-hour of electricity you consume. Everybody should know their grid’s CIPK.
Calculating Ontario’s CIPK is an easy three-step process:
- Multiply total megawatts, or MW, in Table 1 or 2 by 1,000. This converts megawatts to kilowatts.
- Multiply total metric tons CO2 by 1,000,000 (one million). This converts tons to grams.
- Divide the total grams of CO2 by the total kilowatts.
Your mention of Becquerel’s discovery of radioactivity reminds me of a story of *another* famous name in science history, a name I can’t remember, who also discovered that uranium fogs photographic film, but reasoned, approximately, “Lots of things fog film. No need to look for any weird science in this”.
By interesting coincidence, it was also in 1896 that Svante Arrhenius published his seminal paper on what is now called anthropogenic climate change. He attempted to quantify the problem, which he did not view as a problem (given Sweden’s cold climate); Bequerel found the solution, which he barely understood at all.