No, EVs Aren’t Going To Overload Electric Grids

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A few weeks ago, right-wing media site NewsMax ran a piece centered around an out-of-context Elon Musk quote. “If we shift all transport to electric than electricity demand approximately doubles … this is going to create a lot of challenges with the grid,” NewsMax quoted Musk as saying, before going on to scare readers about electric vehicles.

In response, I saw a great number of right-wing commentators and their idiotic fans parrot the quote and then further exaggerate it. They even mixed in recent lies by Greg Abbott, telling us that we are already getting screwed by unreliable renewables, and that EVs are only going to make the problem worse. In other words, EVs are going to kill people! Elon Musk said so!

There’s just one problem: basically none of this is true. In this article, I’m going to give readers the lowdown on the grid situation and give you some factual arguments you can use the next time people start sharing that kind of alarmist nonsense.

Point #1: EVs Use Far Less Energy Than Gas & Diesel Vehicles

When people with an axe to grind against EVs tell us about how bad EVs are, they tend to act like they’ll need just as much energy as gas-powered cars do, but in the form of electricity. They act like you’re basically stuffing coal into the “gas tank” of an EV, so you know that it must be worse.

In reality, EVs only use ¼ to ⅓ the energy of a comparable gas-powered vehicle. Why? Because most of the energy of fossil fuels ends up as heat. Gas and diesel vehicles need a big radiator and water pump to get rid of a lot of heat when the fuel is burned. More heat escapes right out the side of the engine block. Even more heat comes out of the vehicle’s exhaust pipe. There’s such an abundance of waste heat, that automakers use some of it to heat the vehicle’s interior in the winter via the heater core.

By the time all is said and done, about ¾ of a gas car’s fuel and ⅔ of a diesel car’s fuel ends up as waste heat that the car needs to shed somehow. The rest of the energy then goes on to be wasted by crappy aerodynamic efficiency, complex drivetrains, and friction braking. Very little ends up actually pushing the vehicle forward.

Let’s talk about brakes for a second. The Law of Conservation of Energy tells us that energy can’t be destroyed. It can only be converted to different forms. All of the energy of a moving vehicle (thousands of pounds of steel, glass, plastic, and rubber) has to go somewhere when you press the brake pedal. Brakes end up turning that kinetic energy into heat.

EVs have a big advantage here. Not only is about 10% of energy lost as waste heat, but when you use the brakes on a Tesla or a Chevy Bolt, the vehicle’s motor gets used as a generator to slow the car down while actually generating electricity instead of waste heat. This is called regenerative braking.

All in all, around 90% of an EV’s energy actually gets used to move the vehicle instead of getting turned into useless and problematic heat. So, no, changing a gas car out for an EV doesn’t mean that the equivalent energy must come from a power plant. Far less overall energy is needed.

Point #2: Load Timing & Variable Grid Demand

Looking at the power grid and the total power produced in simple terms (example: “We’ll need twice as much”) isn’t informative, because the amount of power that the grid delivers to homes and businesses varies hourly. In Phoenix, the electric grid is taxed to the max in the late afternoon, when things are the hottest outside. Everybody and their dogs are running refrigerated air conditioners, and that all adds up to a lot of power.

Fast forward to midnight. The sun set hours ago, and the desert rapidly cools off up to 40 degrees. During the summer, people still need air conditioning, but the compressors (the part that uses the most electricity) only run periodically to keep houses cool. With all of the power demand cut in half, or less, some power plants are set to produce less power and other plants are turned off entirely.

The grid’s wiring has to be built for the maximum power needed, though. You can’t take the average power used in a day and put in wires that can only handle that much power (assuming you don’t want a fire). You have to take the power needs of the grid at their highest peaks on the worst days of the year and design for that, even though you won’t need those beefy wires the rest of the time.

So, in reality, the grid has tons of spare capacity most of the time. In the middle of the night when power is needed the least, grids are often only transmitting half of the power they are capable of sending, or less.

The Arizona example doesn’t apply everywhere, as some places that actually have a winter use a lot of electric power at night for heating. Other places often have a glut of excess solar power during the day that they don’t know what to do with. Sometimes they even have to pay people to take the power.

Fortunately, EVs can charge during off-peak times when there’s extra power capacity. Utilities often offer customers with an EV excellent prices to charge during those off-peak hours, so they set the EV to charge during those times instead of when everyone is competing for power.

Point #3: EV Efficiency Continues To Improve

Finally, it’s worth noting that EVs are getting more efficient. They were already far more efficient than gas-powered vehicles to begin with, but today’s EVs tend to use even less power than the EVs made ten years ago. Improved drivetrains, better aerodynamic efficiency, better battery technology, and even the use of on-board solar panels are all reducing the power needs of EVs.

Vehicles like the Aptera and Sono Sion are even going to be able to operate almost completely independent of the grid, because they’ll produce enough solar power that they just don’t need to be plugged in most days.

When we keep all of this in mind (EVs are more efficient, they can charge when the grid has the most spare capacity, and they’re getting more efficient over time), there’s really no reason to fear EVs overloading grids unless you’re looking for something to dishonestly smear the EV industry with.

Featured image by Aptera.