Could Britain short circuit without an upgrade?

The latest news from the world of EVs

Hello and welcome back to The Fast Charge, a British EV newsletter. 

In today’s newsletter… not much news but quite a lot on household power supplies and whether it will suffice in the future.

As ever, do drop me an email at if you have any feedback, questions or comments.

In the news…

CENTURY OLD: Really nice story (good PR) about a chap who is 101 years old and tried out a Mache-E recently. The bloke had first learned to drive back in 1936 in a Ford Model T - which was a car that changed the face of motoring. Read more.

TESLA BOT: During an AI day this week, Elon Musk revealed that Tesla was looking at building a humanoid bot to do human tasks. He’s often come out with mad ideas like this before and failed to deliver on them. However, it’s good PR all the same - what was it Oscar Wilde said about being talked about at all costs? The images released by Tesla about the bot were all very space-age - albeit, the video of a man in a ‘bot’ suit was a bit Del Boy of him. Read more on Sky News.

CHANNEL TRIAL: Many moons ago, Oxford council (backed by the government) began a trial to install gulleys outside people’s homes to put charging cables through. This was one solution to address the many millions of people who do not have off-street parking. It seems Oxford has renewed the trial for a further year. This time they are looking for 30 more residents to join the program. It should be completed by January 2022. Read more.

FLAT RATE: News this week from OVO who have initiated a price battle with other EV energy providers. Thanks to a clever bit of software kit OVO is using, they are now able to offer every one of their EV customers a flat rate of 5p per kWh. It follows a successful trial earlier this year. I wonder how the likes of Octopus and Good Energy will respond. Read more.

POST-EV6: According to Auto Express, Korean brand Kia is going to follow up their successful launch of the EV6 - that very sleek looking competitor to Ioniq 5 - by launching two new SUV models. One will be for a European audience and another larger one will be aimed at the American market. Read more.

Could Britain short circuit without an upgrade?

If you were to paint a picture based on what politicians and scientists told us the future will look like, it’ll probably look something like this.

You wake up in your well-insulated house, warmed up by a heat pump. After having your eco shower, you make your way downstairs to the kitchen where you make a cup of tea and put on BBC Breakfast. The kettle and TV, like every part of your house, is powered by green energy. Most of the time this is wind power, earned off the coast and stored in a ‘house battery’ for use in the day, but sometimes it’s solar too.

It's all lovely, and after you finish breakfast, you kiss your better half goodbye as you both drive off in your electric cars, which were charged up overnight.

However, as brilliant as that sounds, we may all need to take ‘the red pill’. Because the reality for millions of homes in the UK is that, by the time you put the kettle on in this future world, your mains box could blow! Or at the very least, be quite stressed.

Why will this happen?

As you might already be aware, buildings across our land get electricity from a grid which spans from the top of Scotland to the tip of Cornwall. Our buildings receive their electricity from cables which come off the grid and through a mains box. This box contains many switches, fuses and controls. We’re probably all very familiar with it.

But, what you might not know is, some houses get a different amount of electricity from others. Most homes across the UK receive something called ‘single-phase’ electricity.

Single-phase electricity is so named because it’s, in essence, a tributary away from the main power supply that goes up and down the country. The main power, before it’s split into different homes, is called ‘three-phase’ (often typed 3-phase).

Single-phase electricity has been getting supplied to British homes since World War 2. It’s powerful stuff. Not only was it able to cope with the early energy demands of post-war Britain, but even today it can manage electric ovens, TVs, multiple charging devices, coffee makers and even EV chargepoints.

This is because most single-phase supplies can give out around 100amps to a household. It takes a hell of a lot to bust that limit, which is why for nearly 80 years it’s served us well.

But, will it serve us in the future?

According to many, including the Renewable Energy Association, single-phase power could have its limitations if we want to have green homes in the decades ahead. In fact, in 2018 they pushed the government to make it mandatory for all newly built homes to have a 3-phase connection.

“Three-phase connections should be introduced as standard as this can be done for only a slightly higher cost to at present and will become even more pressing given Government commitments in The Road to Zero Strategy”, they said in a 2018 report.

The REA was concerned that, without enforcement, developers would continue to keep their margins low and thus keep installing single-phase power to homes – despite it being inadequate for future demands.

Back in the present day, 3-phase electricity supplies are still very uncommon in homes (though very common for commercial properties). However, increasingly many new homes (especially larger ones) are built with 3-phase connectivity installed. That’s not because of government intervention but changing consumer tastes.

Do we need 3-phase power?

Not all of us. However, many might. To demonstrate, let me break it down.

Let’s say you have a typical single-phase supply to your home (about 21kw to 24kW of power). If you had an EV on your drive and a standard 7.4 kW home charger, using it immediately leaves your home with about 14-17kW capacity left.

That’s loads, you might think. But then if you add a basic heat pump to the mix (which is what the government will one day ask that we have), that could take away another 6kW (at least!).

This leaves a mere 8-12kW of power for your lights, electrical devices (such as a TV, console or phone chargers) and everything else electric. Like your dishwasher, oven, fridge or shower. And that’s when you enter overload territory.

This scenario also doesn’t even consider the possible future that we’ll have many homes with two EVs that require charging – lest we not forget, over 20 million households have at least one car currently.

3-phase benefits for EVs

Not only can it help with a household’s load and future proof them, having a 3-phase power supply can also mean people can install 3-phase home chargers. These have the capacity to charge up to 22kW – from your driveway!

“As car ranges and consumer uptake grows”, wrote the REA about EV’s, “it is pragmatic to begin equipping people with the ability for a higher charge rate (particularly when seen in the context of solar and electric heat deployment).”

3-phase power could dramatically reduce how long people must be plugged in for at home and could literally turn every driveway into a rapid charger. The REA believes this could also boost confidence amongst wary EV households.

“Depending on how networks, regulators, and Government decide to ‘manage’ peak EV charging times in different regions, be it through direct intervention or market mechanisms, an 11kW charger on a three-phase system would create additional consumer confidence that they would be able to take a significant overnight charge.”

There is no denying that even in 2021, the idea of widespread 3-phase supply in the UK is as lofty as the Tesla bot. In fact, 3-phase power is so advanced for current products that most EVs can’t even accept 22kW of AC power – such as the Tesla Model 3 which is limited to just 11kW. However, that doesn’t mean in future that this won’t go up, much like the DC speed rates of new EVs.

And the proof is in the pudding as many current EV owners are investing in 3-phase. “Ours is being done Thursday,” one person told me on Facebook. Elsewhere, I’ve seen dozens of forum posts from owners who have installed 3-phase chargers. They’ve been able to do it because of an increasingly wide selection of 22kW (3-phase) chargers from brands like Zappi, EO and Pod Point.

Albeit, others seem to be unaware of what 3-phase even is and its uses.

But who can blame the unaware, I’m sure most people just assume electricity is electricity? I certainly had no knowledge of 3-phase until recently. Although, I’m sure people will soon start talking once they hear how much it costs.

The cost of higher power

“Not cheap…” that’s the summary of EV Youtuber Nick Raimo. On Facebook, he explained to me the cost “depends how far you are from the electric substation normally.” Adding: “A newish build estate cost can be around £1,000 from DNO, but some people pay close to £3,000.”

The DNO is that big grid I mentioned earlier which is run by organisations like SSE. The cost to have 3-phase correlates to how far away you are from it. That’s because you not only have to pay for an upgrade, but there’s also cabling costs, building trenches, and putting in a new meter.

Some companies suggest the costs for 3-phase supplies can rise into the tens of thousands of pounds, especially if you’re rural. The website Smart Home Charge suggests an upgraded electric supply is very expensive with “costs ranging from £3,000 to £15,000”.

For this reason, their editor, Danny Morgan, doesn’t believe it’s necessary. “For most drivers who will be merely topping up their vehicle every other night, for example, a 7.4kW charger is more than adequate.” Morgan sees some benefits though: “Three-phase 22kW charging can be useful if you need to charge multiple EVs. For instance, if there are a few electric cars at home it might give you a few more charging options.”

The future

It’s hard to say whether in the future we’ll all need a 3-phase supply. I suspect for millions of homes it won’t be necessary or needed. As the REA wrote in their report: “Retrofitting established developments will be more challenging and will incur higher costs than new-build, especially in builds pre-1970.” So, many will probably just learn to live without.

However, I also know that as a nation we’ve been here before with broadband, double-glazed windows, phone networks and even boilers. The future will come at us very fast and with unwavering new demands on our infrastructure. Just think, 10 years ago a 7kW public charger was considered fast. Since then, it’s gone to 50kW, 100kW and now 350kW.

3-phase is currently so expensive that I suspect it will only interest hobbyists and the wealthy. However, perhaps if there is enough demand prices will come down. I guess we’ll wait and see.

By Tom Riley