QTRS July 3, 2025

Graphs, commentary, and interesting content for the curious

As I see it…

About 15 years ago we planted two pin oaks in the back of our house, which is the side of the house that gets the summer sun. Those two trees now shade the back of the house in the summer and provide a wonderful outdoor eating space. Even during the recent heat wave, which got me thinking about this, it was a usable space, while before we planted the trees, the space wasn’t very usable before we planted the trees and they grew enough. The house is old enough that one wonders why there weren’t a couple of trees there when we moved in.

As I see it, we have built a society that is fragile and reliant on energy. Why plant trees and have to deal with cleaning up leaves and the possibility they fall on the house when AC is affordable? When I drive around, I keep seeing homes and wonder why they don’t have a couple of shade trees. Trees are such a wonderful way to lower cooling costs and reduce the impact of hot summer days.

We can talk about the increased chance of extreme heat with climate change, but even without climate change, what happens to people in big cities, or even small ones, when a heat wave hits and the power goes out? There aren’t many places where people can go to stay cool. What would happen if cities couldn't receive food deliveries for a few weeks? Supermarkets tend to have about 3 days worth of stock. What happens when the internet and cell phone service go out for an extended period? One common answer to these questions is that none of these scenarios will ever occur.

Our lives, especially those in the cities, are very fragile. The first city to reach 1 million residents was Rome, around 133 BCE, and it stayed above 1 million for 400–500 years. Rome’s eventual collapse reduced the population below a million, and it wasn’t until around 1800 when the next city, London, broke the 1 million mark. Big cities are fragile, and so are complex systems such as the internet, electricity delivery, and our supply chain.

As a thought experiment, think about how you and your neighborhood would handle an extended power outage or empty supermarkets. Climate change increases the likelihood of extreme events, but even without it, we may already be at risk and should consider greater resilience as part of our adaptive strategies.

Let’s go to data.

Electricity demand

The eia provides a look at the spike of electricity during the recent heatwave (PJM is a northeast grid operator). We see a jump from around 120,000 megwatthours to 160,000 megawatthours. That's a 33% spike in demand. I’m also not sure solar and wind with battery storage can handle that.

Real-time wholesale electricity prices on June 23 peaked at $1,334 per megawatthour (MWh) at 7:00 p.m. according to PJM, compared with peak prices of $52/MWh on June 16.

At peak load on June 23, 44% of PJM’s generation came from natural gas, 20% from nuclear, 19% from coal, and 6% from solar. The remaining generation came from a mix of hydro, wind, petroleum, and other generation. Petroleum generation, which is generally the most expensive form and therefore only used to meet large demand loads, was three times greater compared with the same hour the day prior.

One more from the eia

It is worth reminding ourselves how important fossil fuels have been and continue to be to our lives. The graph here from the eia is energy use since 1176. You can complain about CO₂ emissions and pollution, but we don’t have the standard of living we have grown accustomed to without fossil fuels. Meanwhile, renewables play a minor role in the energy landscape. Reminder: Don’t confuse electricity with overall energy.

Population changes

The Census Bureau produced (6/26/2025) this excellent graph to illustrate the shifting demographics of more adults and fewer kids. We refer to this as a population pyramid because it should resemble the shape of a pyramid. I’ve noted this before, but it is worth repeating, since I’m on a doom and gloom role today, that the decline in children is not just a problem for higher education but for society as a whole, with fewer workers and consumers and too many retired adults and not enough younger workers to pay into social security.

The two Americas

I know the U.S. isn't perfect, but it's one of, if not the, freest, most open, and most prosperous societies. Despite this, according to Gallup (6/30/2025), Democrats pride in the U.S. has fallen off a cliff, while Republicans have remained high, even when Biden was in office. I believe it is difficult to address problems when there are two groups with such differing perspectives on society, especially since neither side seems willing to work with or listen to the other.

Fast food

This graph comes from the CDC report Fast Food Intake Among Adults in the United States, August 2021–August 2023 (6/26/2025). I won’t comment on the graph directly, but I will give you my thoughts on eating.

First, dieting doesn’t work because it is often perceived as a temporary activity rather than a long-term lifestyle change. If you go back to the way you were eating, your weight will do the same.

Second, as you get older, you need fewer calories. To stay healthy as you age, you will need to change the way you eat regularly and permanently. As you age, focus on nutrient-dense food that is lower in calories. I’m not saying this is easy, but I can say fast food is generally not nutrient dense nor low in calories.

Data center update

Meta in talks for $29bn data center financing (6/30/2025)

The spinning CD

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Comments

Please let me know if you think I expressed something incorrectly or misinterpreted the data. I would rather know the truth and understand the world than simply be correct. I welcome comments and disagreement. I encourage you to share article ideas, feedback, or any other thoughts at briefedbydata@substack.com.

Bio

I am a tenured mathematics professor at Ithaca College, holding a PhD in math (stochastic processes), an MS in applied statistics, an MS in math, a BS in math, and a BS in exercise science. I consider myself an accidental academic (opinions are my own). I am a gardener, drummer, rower, runner, inline skater, 46er, and R user. I’ve written the textbooks “R for College Mathematics and Statistics” and “Applied Calculus with R.” I welcome any collaborations, and I’m open to job offers.