General Forum - UK Electric grid voltage drop!

UK Electric grid voltage drop!

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URL: https://forum.speakerplans.com/forum_posts.asp?TID=109293
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Topic: UK Electric grid voltage drop!

Posted By: opus jody
Subject: UK Electric grid voltage drop!
Date Posted: 28 October 2025 at 1:20pm

Uk electric is apparently due to be dropped to a lower level, with the lowest 'acceptable' level being 207v

(presumably 220v - 10%?)

The reasoning being problems with micro-generation of residential solar or something.

Nothing-burger? or OMG!!! Dead

I quite like 250v personally.

raises the clip point. ;)

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Replies:

Posted By: madboffin
Date Posted: 28 October 2025 at 4:28pm

Where did you read this?

The whole of Europe uses the standard 230/400V +10% / -6% and it would be daft to change it.

Think of all the industrial processes (and my electric kettle, toaster, and fan oven) that would take longer.

Having said that it's often a bit over 6% high here, 245 or 246.

Is this another example of shrinkflation - or enshittification?

Posted By: Timebomb
Date Posted: 28 October 2025 at 6:39pm

All the micro generation going in has pushed the voltage up, so i cant see how they put it down to 220V.

I got an offer to connect 2 x 8KW but by the time i had put the system in they said the max i can export is 2 x 3.68KW (16 amp) as the voltage in the area is already high due to all the solar thats already been connected, they said they had been taking turns off the transformer at the substation down the road to keep the voltage down.

Any inverter connected to the grid has to be type approved by the ENA and they are all 230 so i cant see how they could change it.

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James@soundgear.co.uk www.soundgear.co.uk

Posted By: Earplug
Date Posted: 29 October 2025 at 7:45am

Under voltage can be dangerous & a problem for some equipment, so this seems unlikely. Or maybe gov.uk preparing for a 110v supply like in the USofA, in order to become that much treasured status of the 51st State!! LOL

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Earplugs Are For Wimps!

Posted By: opus jody
Date Posted: 29 October 2025 at 9:42am

'Electrical news weekly' https://www.youtube.com/watch?v=pKwOIW3YWuo&t=1s" rel="nofollow - https://www.youtube.com/watch?v=pKwOIW3YWuo&t=1s

Proposed UK Electric Grid Voltage DropThe UK's electricity grid is undergoing significant proposals for modernization as part of its push toward decarbonization and net-zero emissions by 2050, with an accelerated target for clean power by 2030. A key aspect of these proposals involves addressing "voltage drop"—the natural reduction in voltage as electricity travels through the network due to resistance in cables and transformers. Voltage drop is a longstanding challenge, but it's becoming more critical with the rise of renewables (e.g., wind and solar), electric vehicles (EVs), and heat pumps, which increase local demand and exacerbate drops on low-voltage (LV) networks.The proposals focus on deliberate voltage reduction (lowering supply voltage within safe limits) as an energy-saving measure, alongside infrastructure upgrades to handle greater voltage fluctuations. This is not about "dropping" the national standard voltage but optimizing it to reduce waste and losses. Below, I'll break it down based on recent analyses and plans from National Grid and government reports.Current UK Voltage Standards and Challenges

Nominal Voltage: The UK uses a harmonized European standard of 230V ±10% for single-phase domestic supplies (actual range: 207V–253V), with 400V for three-phase systems. However, real-world averages are often higher (~242V), leading to inefficiency.
Voltage Drop Issues:
- In LV networks (e.g., 230V to homes), voltages are set high (up to 253V) at substations to compensate for natural drops along cables (typically 5–10% due to load and distance).
- Losses are significant: Overall grid losses are ~2.6% at high voltage (HV, >132kV), but rise to 6.4% at medium voltage (MV, 11–33kV) and 12.2% at LV. This equates to ~7.7% total distribution losses, wasting billions in energy costs.
- Peak evening demand (e.g., from EVs and heating) can cause drops below 216V (the -6% limit), risking equipment damage or blackouts.
Why It's a Problem Now: The UK's "Rapid Decarbonisation of the GB Electricity System" report (2024) highlights that electrification (EVs, heat pumps) will increase LV demand by 2–3x by 2030, straining the aging grid. Without changes, voltage instability could hinder the £77 billion transmission upgrade planned for 2026–2031.

Key Proposals for Voltage ManagementNational Grid's innovation projects and the government's 2030 clean power mission propose targeted voltage reductions and controls to minimize drops and losses:

Voltage Reduction Analysis (VRA) Project (National Grid, 2010s–Ongoing):
- Core Idea: Reduce LV supply voltage by 5–10% (e.g., from 242V to 230V or lower) to cut energy use, as power consumption in resistive loads (e.g., lights, heaters) drops roughly with the square of the voltage (P = V²/R).
- Expected Benefits:
  - Energy savings: 2–5% reduction in consumption (up to 10 TWh/year nationally, saving ~£1–2 billion).
  - Lower peak demand: Reduces strain during evenings, easing voltage drops.
  - Environmental: Supports net-zero by cutting emissions from fossil backups.
- Testing: Real-world trials on monitored networks showed voltage drops of 3–7% without violating limits (230V +10%/-6%). Benefits vary by load type—e.g., resistive loads save more than electronics.
- Implementation: Rolled out via smart transformers and automated controls at 33/11kV substations. Part of the Low Carbon Networks Fund (LCNF) and Innovation Funding Incentive (IFI).
Grid Code Review (Ongoing, 2024–2025):
- Proposes revising frequency and voltage operating ranges in the Grid Code (e.g., tighter HV limits from 400kV to 275kV) to handle renewables' variability.
- Includes dynamic voltage control: AI-managed "active" networks that adjust voltage in real-time to prevent drops, especially in EV-heavy areas.
- Ties into the £77 billion investment for HVDC lines and interconnectors to reduce north-south flow (11 GW average), minimizing long-distance drops.
Low-Voltage Network Enhancements:
- Managed EV Charging: Tools like Managed Electric Vehicle Charging (MEVC) stagger charging to avoid simultaneous voltage dips.
- Voltage Limits Assessment: National Grid Electricity Distribution proposes stricter LV monitoring (e.g., no drops below 216V) with smart meters to flag issues.
- Harmonization Legacy: The UK pays a "voltage premium" (~5–10% higher than Europe's 220V average), wasting energy. Proposals encourage voluntary optimization to 230V exact.

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Posted By: fudge22
Date Posted: 30 October 2025 at 10:59am

Re: Electrical news weekly.

Is the text an AI generated summary of the video, or some derived prompt, that is linked to in the post?

Whilst a search on the ofgem website for “grid code review” (term used in point 2) brings up 178 results, none seem relevant to the topic proposed in this thread.

“grid voltage regulation” doesn’t bring up anything relevant on the ofgem website either.

The only source for the proposal I could find was eFIXX, so the cynic in me says that this is a nothing burger and the news topic was to mainly to generate “engagement” from the viewers.

Posted By: madboffin
Date Posted: 30 October 2025 at 4:25pm

How will this reduce power consumption?

If you need a given amount of energy to heat someting (boil the kettle or complete an industrial process) that's measured in kWh, i.e. power x time.

Lowering the voltage just means it takes longer to do the same job. It doesn't reduce the total energy requirement.

Posted By: opus jody
Date Posted: 31 October 2025 at 9:43am

"Is the text an AI generated summary of the video, or some derived prompt, that is linked to in the post?"
I saw the video, then AI'd it.

"so the cynic in me...."
Yaa. seems like it. Just normal burgering around with the optimisations.

"How will this reduce power consumption?"
lol, I thought that.
less voltage = more current :D
I guess they're on about reducing losses, where a chunky 240v+ isn't needed

ok, cool, seems like a nothing burger.

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Improvised Hardware Music http://vimeo.com/user9389813/videos

Posted By: Earplug
Date Posted: 31 October 2025 at 11:53am

As mentioned above, lower supply voltage = earlier clipping, so not a good thing for the audio world.

It does sound a lot like the UK grid just isn't up to supplying the power needed to charge all those electric cars - & cycles(!), never mind what's needed for all those AI centers, so maybe people are being prepared for the large voltage drops you're going to have during peak hours. Just another bit of Broken Britain. Shit in the streets, shit in the water & power drop-outs like some s-hole 3rd world country... Ouch

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Earplugs Are For Wimps!

Posted By: madboffin
Date Posted: 31 October 2025 at 1:22pm

Earplug wrote:

maybe people are being prepared for the large voltage drops you're going to have during peak hours.

That's quite possible, stories like this are often planted to "soften up" people for what's to come.

The main reason for changing everyone in the UK over to smart meters is to enable "selective availability". Each meter has a remote isolator switch that can be individually addressed, so they can cut off your power at will. That's not just for people who fail to pay the bill, it's to enable rolling power cuts for consumers, but with some being exempt (home dialysis machines etc).

Also they are trying to persuade everyone to get heat pumps instead of gas boilers. Which would be a good idea in theory, but will add even more to demand. About 1kW per unit, and you need several, running continuously, to heat a house.

(And I don't know what the difference is where you are, but in the UK electricity costs four times as much as gas, and even after allowing for efficiency differences a heat pump's output needs to be at least 3.5 times its electrical input to be economically viable compared to a gas boiler)

Posted By: Andylaser
Date Posted: 31 October 2025 at 1:36pm

I am surprised we didnt align fully with Europe at 230v. I know we are technically "in spec" but voltage here is often around 250v.

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"music so loud, that if we move in next door to you; your lawn will die" - Lemmy

Posted By: madboffin
Date Posted: 31 October 2025 at 2:19pm

The whole thing was really a fudge. The idea was that true alignment would be a very long-term process, if it happened at all.

Actually changing the voltages would have cost a disproportionate amount of money for just 10V or so of difference. All over Europe, most of the power companies were either recently privatized or being fattened up for privatization. The cost would have affected shareholders' dividends and bosses' bonuses, or put off potential buyers.

Posted By: Earplug
Date Posted: 31 October 2025 at 2:50pm

"That's quite possible, stories like this are often planted to "soften up" people for what's to come."

Yes, flying a balloon to see the reaction.

The big gap in power generation are the proposed AI centers. Microsoft, for example are paying for the opening a closed down reactor at 3 Mile Island! And Google are looking at opening other closed down reactors. If the UK hope to keep up with this - as stated by gov.uk, they will have to (help) fund a huge increase in the capacity of the country.

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Earplugs Are For Wimps!

Posted By: woody2
Date Posted: 31 October 2025 at 7:36pm

Earplug wrote:

As mentioned above, lower supply voltage = earlier clipping, so not a good thing for the audio world.

Yet spain had the biggest blackout in 20 years......... Ouch

Posted By: fudge22
Date Posted: 31 October 2025 at 8:13pm

Did anyone actually watch the video? The concern outlined was that the DNO’s are more worried about over voltage than wanting to reduce voltage as means of reducing power consumption. The AI generated summary is crap. Even if proposals mentioned are adopted the average voltage would still be over the nominal 230V and the lower legal limit would still be the same as European mainland voltages

How will this reduce power consumption?

You need to use a “smart” meter, obviously.

lol, I thought that.
less voltage = more current :D
I guess they're on about reducing losses, where a chunky 240v+ isn't needed

With a purely resistive load, I =V/R, so assuming a constant resistance lowering the voltage will also lower the current. With reactive loads it is not so simple.

Madboffin’s example of boiling a kettle has to do with thermodynamics and energy. It takes a fixed amount of energy to boil a litre of water. Decreasing the power just means it takes longer to boil.

As mentioned above, lower supply voltage = earlier clipping, so not a good thing for the audio world.

Switched mode PSUs use feedback to regulate the output voltage. Lowering the mains/input voltage slightly shouldn’t have any effect. Some devices will work happily with any supply voltage between 90 and 250.

For amplifiers with unregulated supplies, the difference will likely be negligible. Plugging a kettle, or another amplifier, into a socket next to your amplifier will reduce its output too.

so maybe people are being prepared for the large voltage drops you're going to have during peak hours

There are more likely to be complaints if devices go into protect mode or fail due to over voltage than complaints because a kettle took 20 seconds longer to boil. All my computer equipment runs from a hybrid solar inverter. I left the output voltage at the default 228V. Believe it or not, the sky didn’t fall in.

I still haven’t found any official notification that this is a thing anyway. Neither, a direct search on ofgem’s web site, google, chatgpt nor Grok bought up any results for me. I may just be bad at internet searches, but getting worked up about something mentioned on a YouTube video or some AI generated junk is not worth the stress.

Whether the grid can cope with future demands is a different subject.