It’s summer, and that means blockbusters. And for “Marketplace Tech,” it means an occasional look at sci-fi movies and their visions of the future.

In 1985, “Mad Max Beyond Thunderdome” hit the big screen. Mel Gibson and Tina Turner battled in a post-apocalyptic wasteland. You might remember the crazy cars, the eponymous Thunderdome — basically Cirque du Soleil with chainsaws. In the film, fossil fuels are gone. The main energy source is methane from … pig feces.

“Marketplace’s” Jed Kim spoke with Matthew Kahn, an economist at Johns Hopkins University, about the energy technology and economics on display in “Mad Max.” He said that for him, the movie shows how free markets falter in a post-apocalyptic world. The following is an edited transcript of their conversation.

Matthew Kahn: A very interesting issue is property rights in that movie. I don’t remember judges [in the film]; I don’t remember police. I don’t remember lawyers. I remember physical violence and lots of Mel Gibson jumping on top of fast-moving vehicles. When the rule of law breaks down, it’s very difficult to use market prices. But when we can use market prices, they signal scarcity. There’s something unsexy about the price system, but it plays a very crucial role in allocating scarce resources — in this case, energy.

Jed Kim: Do you think it is possible that society and our economy would break down over these sustainability issues?

If there’s a tremendous demand for energy, and if we solely rely on gasoline to provide that energy, then there could be limits to growth.

Matthew Kahn

Kahn: No, and you just posed the $64,000 question in environmental economics. If there’s a tremendous demand for energy, and if we solely rely on gasoline to provide that energy, then there could be limits to growth. But a point that economists make is how entrepreneurs think about the future. A young Elon Musk, a young Mark Zuckerberg — perhaps these guys saw the “Mad Max” movies [and see] that we will face limits to fossil fuel supply in the future. That creates an incentive for these folks to innovate and to work with engineers and venture capitalists to fund breakthrough technologies like solar and electric cars.

Kim: So maybe that’s what the film gets wrong, that in reality people would have innovated their way away from this bleak future.

Kahn: This is what fascinates me. We can only have these breakthrough technologies if men and women make the sacrifices to invest in the nerdy stuff and in the venture capital to make these risky innovations possible. There’s a question: Where does their imagination come from?

So let’s do an example. Suppose that entrepreneurs thought that there will be a future demand for baldness medicine, but it never occurred to them that there’d be finite energy in the future. In that case, they would focus on baldness innovation, and we’d spend no time on energy innovation. So a very interesting question is how entrepreneurs — as they think about the future — what do they think is our future scarcity? Mel Gibson in “Mad Max” may have helped to preclude that apocalyptic future [by depicting the impact of future energy scarcity].

Kim: Let’s say you have assigned your students the homework of watching “Mad Max Beyond Thunderdome,” and they come to class and they’re, like, “Professor, why did I watch this?” What’s the economic principle you want them to take away?

Kahn: Perhaps the only lesson in economics is that there is supply and there’s demand. If we only have ever-rising demand for resources, we really can strip out all the trees, pollute the water, use all our energy. If there’s never a supply response, ever-growing demand really could strip down our world of the key resources perhaps we take for granted. What I would want my students to see is the possibility that with human ingenuity that we can augment our resources.

Related links: more insight from Jed Kim

The “Mad Max” series essentially fetishizes cars, so that’s what I’m focused on today. First, “Mad Max: Fury Road” is an oldie, but it’s still fun to think about and watch. Back in 2015, when the movie came out, Bloomberg broke down the fantastical cars that made “Fury Road” so memorable. My favorite of all time, the Doof Wagon, featured walls of speakers and a flame-throwing electric guitar. Apparently, it takes a supercharged V8 engine to make that monstrosity move.

But future villainous vehicles might be scarier if they never ran out of fuel, right? What is the future of solar-powered vehicles? CleanTechnica looks at the current state of the technology. Toyota is testing out a car that’s covered with solar panels. The car’s not that revolutionary — essentially a plug-in hybrid. The solar panels, though, are twice as efficient as the ones people are putting on their houses these days. They give the car 27 miles of range a day, which is significant because Americans typically drive about 29 miles a day. And solar advances could improve that range to 81 miles a day. It’d be a game-changer for people who live in places where electric charging isn’t available. Plus, the panels make it look like the cars are armored.