Solar and EVs are a disaster

[cupoftea]

Hi,
On many channels (not here) , it was stated that solar was going to have the problem that it raises the grid voltage and sometimes so high that EV chargepoints wont work.
(as well as causing other problems)
Here we see that those predictions, which were all refuted, (not by edaboarders), have come true...

First thing is that it appears that stopping an EV from charging just because the grid is >253VAC was a bad rule to bring in.
The Engineer John Ward on youtube had stated (before EVs became popular) that the elec regs were going to have to change otherwise EV charging would not be possible.
It turns out that a bit part new standard was hurried in, and now we have the shown problems.

John Ward

The "hurried in" standard meant that certain very very expensive grounding and earthing procedures would no longer be needed....this was needed because it would have made introduction
of EV chargers pretty well impractical.

Why did they choose 253VAC as the threshold above which EV chargepoints should not work?

 

[D.A.(Tony)Stewart]

That is the industry spec. 230 +/- 10%

I guess he never knew that a pre-load would have corrected the problem or how to make one.

 

[cupoftea]

Sorry, this is the correct John Ward Video

 

[D.A.(Tony)Stewart]

An active voltage limiter with bulbs or a heater would be easy.

Making a Boost regulator operate at a higher input than output peak voltage adds cost to make it Boost + Buck

to correct the design which has too high Voc system which is greater than the peak voltage for 230 Vrms-10%

253 Vac = 358 Vp +10%
230 Vac = 325 Vp nominal
207 Vac = 293 Vp -10%

to have a GTI operate at -10% the boost input voltage must not exceed 293 Vdc in my calculations which could be Voc in a PV system . If it was too high then a dummy load above this voltage could allow the EV charger to operate bringing down the Vdc to Vmpt then the dummy load would be automatically off.

The standards I suppose , may have evolved from this.

My opinions are my own.

T

 

[cupoftea]

Thanks, but i think that could be wasting power. (adding bulb or heater dummy loads)
Anyway, the video in post #3 above shows how EV charging is basically not feasible when you consider it in terms of the electrical regulations of just a few years ago. The Elec Regs were then changed to make it cheaper for people to get EV charging done at home....but now we see from the Artisan video of the top post...that this "Hurried through" amendment of the electrical regs has not been fully thought out....and a whole raft of EV charging problems await us.

Artisan electrics have unearthed what could well be the death of solar and EVs....or some new invention will get invented to get round this issue.

 

[dick_freebird]

A proper design would leave margin around the "must deliver" power company spec range. Regardless its credibility.

 

[cupoftea]

A proper design would leave margin around the "must deliver" power company spec range. Regardless its credibility.

Thas right, and Power companies cannot really have much control over the mains VAC range any more...because the unknown amounts of solar inverters spewing current into it can raise the voltage to goodness knows what.
If you live in a reasonably remote area of say UK and are buying much solar...you are in for a bad surprise.

The TNCS system is a disaster.....you get a break in the combined earth/neutral conductor, and all hell breaks loose.

 

[D.A.(Tony)Stewart]

Redundant contacts/paths to protective earth improves reliability by MTBF squared if independent..

 

[dick_freebird]

Seems farfetched that solar peak capacity would cover base load let alone one or small-% misbehaving sources overcoming the grid.

 

[cupoftea]

Thanks, the vid in the top post shows how if you have solar putting into the grid then you might not be able to charge your EV because any solar you put onto the grid might raise the grid voltage above 253vac. However, i thought the chargepoint systems like myenergi etc were supposed to make sure that your solar system did not put energy out onto the grid, and that any solar was either put into the household battery or into the car battery? I thought that was the whole idea now?....ie, because the profits from exporting are so low, you make your solar system "zero the meter".........ie, zero your electricity meter so you import or export (from/to the grid) as close to zero amps as possible?

 

[D.A.(Tony)Stewart]

Specs include: Disconnects if grid voltage hits 255V or frequency drops to 47 Hz.
This includes expected 1-2 V rise from current injection from GTI within 1 deg of phase error.

Germany also some tighter tolerances for output power above 50.2 Hz indicating a surplus.

 

[FvM]

On many channels (not here) , it was stated that solar was going to have the problem that it raises the grid voltage and sometimes so high that EV chargepoints wont work.

On many channels people are distributing unsubstantiated fake news about regenerative energies. I believe it's an fossil industry lobby and political campaign.

Having said this, I'm interested to hear about real problems associated with distributed solar power and EV chargers.
At Edaboard, I expect textual descriptions rather than YouTube videos.

In general, IEEE Std 1547 "Interconnection and Interoperability of Distributed Energy Resources" specifies mechanisms to control power delivery of solar inverters, preventing inacceptable voltage rise. At least for German power grid, I'm not aware of a disaster coming up, therefore the tenor of the thread sounds to me like alarmism.

 

[cupoftea]

Thanks, the electrician in the top video makes money from installing green tech to peoples houses so he is not pro-fossil fuel.
He is a well known contributor and if he is having such a serious problem (as stated he just installed a multi thousand pounds solar system which doesnt work) then it is worth looking in to. The thread is just to examine what is the actual problem of the video in the top post.
There was a suggestion that solar was pushing the grid voltage up......well solar could do this, but the inverters are supposed to sense the grid voltage first and then not push energy into the grid so i cant work out what's happened here.?

At approx 10:50 of the top video he explains what he thinks the problem is but i dont see how that could happen because the solar GTi would sense the grid volts then just not push energy intio the grid.......this isnt a problem as few people are interested in generating to the grid anyway...as its not well rewarded financially.

The following youtube video explains how the safety problems depicted in the video of post #3 above were solved..
by a change in the electrical regs...
At 29:20 onwards of the video of post #3, John Ward explains why he doesnt seem to think that the regulations that got brought in are valid/safe...because, as he says, the safety trip happens after the person has already gotten electrocuted.

(Who is righteous?...IMHO the new system that Myenergi explains is actually fine)

I'm not aware of a disaster coming up, therefore the tenor of the thread sounds to me like alarmism.

Thanks, yes my apologies, after reviewing the kind feedback here, it seems that the actual problem of the top video is likely the long line run from the transformer to the house concerned...and that the power company may well have tapped up the voltage to account for the long line.....this then is stopping EV chargers from working.
However, the situation was certainly a "disaster" for the customer who made the multi thousand pound purchase and then found that their system did not work.

So the moral of the story is......before installing an EV chargepoint....do a 1 day (or 1 week) logging check of the house voltage to check that your VAC does not go outside 230VAC +10% -6%. I have not seen that stated in any of the chargepoint sales literature.

Throughout the top video, the electrician is saying that the line voltage rise is due to solar GTi's pumping energy into the grid...but this couldnt be so...because solar GTi's detect line voltage before turning on, and wont turn on (wont export to the grid) if the line voltage is >253VAC.

 

[D.A.(Tony)Stewart]

The worst offender of self-inflicted technology stressors on the grid are the "Voltage Stabilizers" , never seen in North America yet common place in India, Pakistan etc.

These servo driven tap changers provide negative feedback to incoming daily cycling of power variations using an algorithm to change taps to boost the voltage in steps when it drops and lower in reverse.

This negative feedback on output voltage change unfortunately is a positive feedback to the grid so that a drop in voltage reacts with a rise in load current leading to instability and long term expensive infrastructure rebuild. A rooftop alternative energy source with storage is too expensive a solution for most home owners.

Judging by the rapid inflation of AI farms and the massive energy needed to power them, this will be another major expense if we get hooked on this. By all massive revenue predictions, the profit seems certain. But who will pay? Everyone, indirectly or direct.

I recall hearing Microsoft will capture the energy of 3 Mile Island's Nuclear power.