It Bears Repeating: Renewables Alone Won’t End the Climate Crisis

In a recent column about the dismal Canadian election, I wrote that most Canadians and their lacklustre political parties have no real appreciation of the physical and moral challenges posed by the disruptive force of climate change.

Although the media still portrays climate change as some vague threat to “the environment,” it is really a self-made blitzkrieg that is already destabilizing a highly energy-intensive and complex human civilization.

Greta Thunberg has spoken prophetically: our civilized house is on fire. 

But our collective politicians, blinded by ideology and technological illusions, refuse to panic, let alone call the community fire department. 

They behave as though they can just build another house somewhere else on Mars, and then watch the conflagration on Netflix.

In that previous analysis, I quoted a Colorado professor, Roger Pielke Jr., who recently noted in Forbes that if we really wanted to reach zero carbon emissions by 2050, and we solely choose wind power as the solution, we’d need to build and deploy 1,500 wind turbines on about 300 square miles every day for the next 30 years.

We can’t do that, of course, because of physics and economics. Pielke was simply illustrating the scale of the challenge if we thought that renewables could do all the work for us.

But a great many readers questioned Pielke’s math; others questioned his motivation. Others questioned my sanity in quoting such a fellow.

Having written about energy for 30 years (and my best scribbling on the matter remains The Energy of Slaves), I thought Pielke’s numbers, which can vary with wind power due to location and size of blades, were largely accurate and conveyed the enormity of the task at hand, especially if we think our energy crisis is just a substitution problem. 

Pielke’s numbers are also a reminder that as of 2018, solar power provided only 2.2 per cent of global energy and wind just 4.8 per cent.

In other words, we have a long way to go if we choose to reduce emissions by simply replacing fossil fuels with wind turbines. As the ecologist Bill Rees noted in his recent Tyee analysis, “the green energy transition is not really happening.”

I asked David Hughes, one of Canada’s most esteemed energy analysts, to comment on Pielke’s math, and here’s what he said.

Pielke, he said, ignored some data on existing renewables such as hydro dams but basically his math “is close to correct.” Hughes added that it’s physically impossible to replace all primary fossil fuel energy on a business-as-usual scale with renewables.

To Hughes, the implications are clear: “What this means is that we have to look at downsizing, degrowth, using less. The math doesn’t work to keep the party going with renewables.” Ecologist Rees delivered the same message a week ago in The Tyee.

Note that Hughes is not saying we shouldn’t build lots of renewables. What he is saying is that we need to radically reduce energy consumption and use renewables to actually retire fossil fuel infrastructure. (To date, the evidence shows that we have largely used renewables to consume more energy.)

Our civilization, which will embrace a collapse before it commits to such a plan in energy reduction, now behaves like a Moloch. The child eater keeps gobbling more energy and belching more emissions.

Since 1859, global energy consumption has increased by an average of 2.4 per cent a year. It shows no sign of slowing down.

Let’s look at the problem another way. The Great Depression, which put millions out of work, represented a 30 per cent drop in economic activity. That economic collapse resulted in only a 10 per cent drop in global carbon emissions. (Scientists know this from ice core work.) Yet we need to bring 42 billion tonnes of yearly emissions down to net zero by 2050.

The destructive ethos of our civilization demands growth and greatness. Its unmanageable complexity has created an insatiable addiction to cheap energy.

But Pielke’s numbers also reflect the different physical character of renewables. They simply don’t behave like fossil fuels, and in some ways that’s probably a good thing. 

They provide less energy; require more space and offer fewer surpluses. They also can’t do a lot of the work now done by fossil fuels, such as steel and cement making. 

The big issue is really something called power density. In many respects, different forms of energy behave like different groups of foods. Some pack a lot of calories and others don’t.

Cheese, for example, contains a lot more calories than a potato, just as fossil fuels offer more bang for the buck than most renewables. As a result, renewables typically require more surface area to produce an equivalent amount of power as fossil fuels. 

Ecologist Vaclav Smil and David Fridley, a fellow of the Post Carbon Institute, have hammered on this energy nail for a long time. As Fridley explains, a “consequence of low energy density is that larger amounts of material or resources are needed to provide the same amount of energy as a denser material or fuel.”

Here’s one example. The world’s largest concentrated solar project sits in Morocco and occupies 25 square kilometres of desert, or 3,500 football fields. The $9-billion Ouarzazate Solar Power Station produces enough electricity for a million people, or the city of Prague.

But Morocco has a population of 35 million people. To provide solar power for everyone, using the big project model, would take $315 billion and 875 square kilometres.

Here’s another illustration: A lithium ion battery, which requires a lot of rare earth mining, can contain about 0.5 megajoules of energy per kilogram of battery. In contrast, gasoline contains 46 megajoules of energy per kilogram.

Power density explains why fossil fuels represent the energy equivalent of fast foods, and are equally as addictive.

David Mackay, a British engineer, deftly illustrated the realities of power density in a book called Sustainable Energy: Without the Hot Air. (Mackay, by the way, thinks society must make a dramatic change and be aware of the math at the same time.)

He also uses energy figures that most people can understand: kilowatts per hour (kWh), or the same numbers that appear on our hydro bills.

The average person in England or Europe, for example, consumes 125 kWh per day.

Most of that energy now comes from fossil fuels. Driving a fossil-fuelled car 50 km a day consumes about 40 kWh per day of that total.

It is hard to make that up with wind power. According to Mackay, you would have to plant 10 per cent of the windiest part of Britain with onshore wind farms to yield just 20 kWh per day per person.

The story gets more complicated. To replace just one-quarter of energy demand with biofuels would require planting 75 per cent of Britain’s landmass with plantations of switch grass or black locust.

To wrest just four per cent of Britain’s energy consumption from ocean wave power would require the construction of 500 km of wave farms along the coast.  

And to provide half of that 125 kWh per person demand with wind would require “filling a sea area twice the size of Wales” with offshore wind farms. 

“Someone who wants to live on renewable energy, but expects the infrastructure associated with that renewable not to be large or intrusive, is deluding himself,” notes Mackay. And he is right.

The U.S. National Renewable Energy Laboratory (and yes, it is surprising that such an organization still exists in the Trump era) calculated in 2018 that if the United States transitioned to 80 per cent renewables by 2050, the power sector would occupy 15 per cent of the landmass in at least 12 states.

Whenever ecologist Smil looks at a wind turbine, he sees fossil fuels: coal-fired blast furnaces melting steel, and diesel-powered machines mixing cement, and more fossil-fuelled machines erecting steel turbines. Even the turbine blades are made from lightweight plastic composite materials. 

Smil estimates that to generate just 25 per cent of global electric demand would require “roughly 450 million metric tons of steel.” And to make all of that steel would require somewhere around 600 million metric tons of coal.

Nonetheless, “a well-sited and well-built wind turbine would generate as much energy as it embodies in less than a year,” writes Smil. “However, all of it will be in the form of intermittent electricity — while its production, installation, and maintenance remain critically dependent on specific fossil energies.”

For the record, Smil thinks society is doing everything wrong with energy at the moment. Our cars and homes have gotten bigger. We fly everywhere like feckless Greek gods, and we grow our food more energy intensively than ever before. We throw away 40 per cent of groceries. We can’t even tax the rich, the world’s biggest energy spenders, properly.

My point here, and I do not wish to belabour it, is that one of the most effective and direct solutions to reducing emissions must come from radically reducing fossil fuel consumption. But such conservation will radically change our economy and de-energize our way of life.

We cannot put the fire out in our global house alone with smart cars, windmills and solar panels.

Furthermore, technology is not an energy maker but an energy cannibal. Supplies of cheap energy drive technological advances. 

“If the quantity or quality of energy resources dwindles, the power of the technology declines along with them,” notes U.S. critic William Ophuls in his brilliant book on failing civilizations, Immoderate Greatness. 

But there is some good news here. The power density of solar panels is increasing. (You can get more solar energy from smaller spaces.) Heat pumps, roof-mounted solar water heaters and turning the thermostat down are no brainers. High-energy prices can and do lower demand. The research consistently shows that low-energy consuming cultures tend to be much happier than profligate ones like ours.

In the 1970s Earl Cook, the renowned Texas geologist, described how cheap fossil fuels had blinded us to the perils of high energy spending by creating its own myths. We thought that endless growth was good and that technology never delivered diminishing returns.

Now we must contemplate an energy descent for which our civilization doesn’t have an ethos or a vocabulary.

But Cook knew where we must go: “We must abandon efficiency of production as a social goal and replace it with efficiency of consumption. We need to favour measures of quality of achievement over measure of quantity. And we must stop confusing momentum with progress and growth with goodness.”

We can start by rejecting the nostrum that we can stabilize the climate and build a New Jerusalem by solely building renewables.