Fact and Fiction: ENOUGH ELECTRICITY?
“There will not be enough electricity and electricity grids will not be able to cope with millions of new electric cars!”
Debunking this myth requires an understanding of how power is generated and delivered. What’s generated is used. Excess energy is very difficult, and expensive, to ‘store’ for when it’s needed at peak demand. Storage only represents a tiny fraction of total electricity output at any given time. Instead, power supply operators rely on back up generation capacity to meet peak demands. In other words, most of the time electricity power plant generators are unused or on low output mode, this can vary by the time of day and year greatly.
The two issues to consider are therefore if there is enough generation capacity to meet electric car needs and if the power grids and power lines can cope. On generation capacity the answer is broadly yes, there is plenty of spare capacity. Indeed, spare capacity is increasing in some developed economies due to greater efficiency of power usage with better energy ratings on household appliances, industrial and business equipment. This combined with more renewable and energy storage solutions is reducing peak demand on power plants.
In the UK for example, in 2002 total peak demand was 62 gigawatts, in 2020 peak demand had dropped to 52 gigawatts. EVs are most usually charged at night, at home in at least 60% of cases. Night-time capacity in most countries is more than sufficient to power entire nations driving EVs. It has been estimated that demand would increase by 10% in the UK, for example, if everyone switched to electric cars. Smart charging, whereby charging can be scheduled through the car’s or wall charger’s software, can be easily set to only charge during low demand, off peak, and often cheaper electricity times. This would further reduce stress on national power supplies.
Globally the world has 8,000 gigawatts of operational electricity generation capacity. Running all capacity at once can produce almost 70 million gigawatt hours of electricity. In 2019 the world consumed around 27 million gigawatt hours of electricity meaning ‘spare or peak’ capacity is about 40 million gigawatts. It has been estimated that the total power required to run the world’s car and transport fleet of over one billion units on electricity would be about 28 million gigawatt hours of electricity. So, in summary there is plenty of spare generation capacity to switch every car in the world to electric today.
However, the current mix of power generation from gas, coal, oil, nuclear and renewables like wind and solar, would mean limited CO2 emissions savings if every car ran on electric. The CO2 emissions drop would only be about 10-15%. What needs to happen is a parallel shift to cleaner sources of energy as we switch over to electric cars. Thankfully this is happening, to varying degrees, around the world and I’ll cover this in a future blog.
However, although the worldwide picture seems to imply there is enough power, it varies from nation to nation. During the 2021 Texas power outages, when its electricity grid failed due to
unexpected demand because of an unusually harsh cold snap, electric cars were rendered inoperable. Unless EV owners had their own storage capacity in their homes, EVs could not be charged. Ironically, had power to grid services been available en masse, EV owners could have powered their homes from their cars, more on this in a future blog.
The issues in Texas were a peak demand limitation as the state never had to deal with such harsh climate conditions for that time of year, arguably a freak weather event caused by climate change. Rolling blackouts also occurred in California in 2020 due to a heat wave as air conditioning power demand stretched power supplies.
The geographic size of the US means there is no single power grid. Regional grids operate independently of each other and cannot share excess power generation. This is common all over the world, in larger countries particularly. Capacity increases are predicted to be necessary in many US states from 2030 onwards. These are not for everyday EV usage but for those peak demand events such as the ones in Texas and California.
Overall, the US power system generates excess energy annually, however unlike in the UK, peak demand is growing. In the year 2000 power plants produced 3.5 trillion kilowatt hours of energy while in 2020 that number had grown to 4.0 trillion kilowatt hours.
The U.S. Department of Energy conducted a study that economic growth combined with increased electricity demands, especially from electric cars, could increase US power consumption by almost 40% by 2050. In California the state predicts that EVs will draw less than 6% of the state’s power generation capacity by 2030. In the US individuals cover around 3.1 trillion miles per year, roughly 13,500 miles per person for America’s 230 million licensed drivers. The total estimated power requirement if every car in the US was electric today would be around 1.2 trillion kilowatt hours. The US could not support an overnight switch to electric cars.
But that’s not going to happen, the switch will be gradual over the next two decades. Even with the exponential shift to EVs, power generation has time to ramp up. This ramp up needs to see a shift away from fossil fuel power generation to renewables, combined with new energy storage solutions for unpredictable peak demand events. This potential additional demand for electricity has to be taken into an historical context. In the US alone, power generation capacity was able to increase five-fold from 1960 to the year 2000, according to the U.S Energy Information Administration. This increase was driven by population growth and the widespread use of new appliances, like at home air conditioning. With a 30 year to full electric car transition forecast (although I believe it will be just 20 years) in the US, just a 30-40% increase in capacity is required, well below historical power increase achievements and a modest challenge for the energy industry.
Power generation is one thing, but can the power lines, substations and homes handle the load? Let’s take your home first. A standard 220v-240v or 110v (for the US) domestic plug with just a 13/16amp fuse can charge your electric car. This will be slow, likely only adding between 8-15 kilometres (5-10miles) of range per hour. This will drain no more than many household appliances, drawing around 7,200 watts or less. This would be a little more than a home air conditioner unit and less than a water heater for example. For faster charging you will need a home charging unit and small fuse upgrade, typically costing between $500-$1000, which can fully charge most of today’s EVs in 3-4hours.
For high speed and super-fast charging, the grids in most countries can handle the load today. This is because most fast chargers are located along major highway routes where high-capacity power lines are often located. Local grids can handle the increased EV load, but not at the same time. If everyone arrived home in the evening at roughly the same time and plugged their cars into the local grid, it could possibly fail, especially given that 6pm-8pm is usually peak power demand. This is why smart charging technologies are necessary to balance the load and charge cars at off peak times. Local energy providers could easy regulate this by charging more for peak and less for off peak usage to encourage EV owners to set charging to start in the middle of the night for example.
Given average driving distances, all night charging is not necessary, 2-3 hours with a standard domestic socket would be enough to meet 90% of daily driving. Of course, this adds a little bit of hassle factor, however most new EVs already have this simple charging scheduler built into their software. Using a smart charging solution largely solves grid and power line peak demand capacity. This would mean today’s infrastructure doesn’t need significant upgrades.
None of this considers the increase in home power generation solutions, like solar panels and solar roofs in many parts of the world. These combined with home energy storage batteries, like Tesla’s Power Wall, will gradually provide a further cushion to power grids. Indeed, given energy storage and peak demand is the number one issue for energy suppliers, a world full of electric cars could actually help to balance and reduce peak demand by tapping into unused power in the cars’ batteries connected to your home’s power supply. Power to grid solutions are already operational in many parts of the world and I’ll cover this in more detail later.
FICTION: There is not enough electricity to power electric cars today. The increase in power generation, with the planned switch to electric cars, will not be able scale up fast enough to produce enough power.
FACT: The world already produces enough excess electricity today to power a world of only electric cars. Power supply today is sufficient to meet the needs of the planned expected shift to electric cars. In some countries, infrastructure upgrades are required, while in others a 20-30% increase in peak capacity is all that is required to power every vehicle in the world. In summary, the world’s electricity supply can handle the switch to electric cars with only modest increases in some places compared to historical power generation achievements
