There happened to be an Ikarus bus exhibition in my local town with buses from all ages including the latest electric bus, a pre production model. It has a 280 kWh battery with a range quoted as 540 km. Fastest charging time quoted as 15% to 100% as 1 hour. - and they routinely charge to 100% as the normal procedure.

Talking to the Rep. the plan is to have electric buses replace the ICE buses over time with several town here already having electric buses. The charging routine would be to charge from 11 pm to 4 am. for 2 reasons 1) buses don't run at night and 2) the power co. like the night time load.

By the time there are fleets of electric buses, lorries, taxies and delivery vans from all the on-line sales not to mention private EVs where will the incentive be for cheap rate 'off peak' electricity.

BTW has anyone heard (other than pure speculation) what plans HM Treasury has to replace the lost revenue from road fuel tax.

Oh - and the drivers absolutely love the electric buses.

If I ordered one of the new buses today delivery is in 3 months. No one was talking about the Grid capacity except one driver who reckoned they would need a direct line to the nuclear power station.

So how long will the cheap night rate electricity last?

and wind

We have an E7 equivalent over here. And on another thread are details of the Octopus Intelligent Go tariff which is a cheap night rate designed to shift EV charging to the night which I presume could also be used for charging domestic batteries over night to selectively feed in during peak times (although I think Octopus require proof of EV ownership (at the moment?).

Hungary has already hit grid problems with domestic PV now limited to 2.5 kWp on single phase domestic installs.

I do wonder how the grid (and power generation) will cope with the rapidly changing electric revolution that appears to be in progress. If there is too much domestic PV and battery storage I can see the standing charges going up significantly with perhaps a tiered system with low grid consumption or grid tied PV being charged a premium.

<blockquote><cite>Posted By: Peter_in_Hungary</cite>If there is too much domestic PV and battery storage I can see the standing charges going up significantly with perhaps a tiered system with low grid consumption or grid tied PV being charged a premium.</blockquote>

I believe that in parts of Australia domestic exporters are charged if they want to export it.

<blockquote><cite>Posted By: Peter_in_Hungary</cite>Hungary has already hit grid problems with domestic PV now limited to 2.5 kWp on single phase domestic installs.</blockquote>

I was limited to 3.6 but can now export 5 but it is rare for it to reach that figure.

Posted By: WillInAberdeenUK now has as many GW of batteries as of nuclear

So that's the end of the claim that nuclear is necessary as base load - if base load can already be supplied from solar via batteries.

There appears to be some confusion at renewableuk.com, since they talk about GW of batteries, which is certainly important but cannot be sensibly discussed without also knowing the GWh of the batteries! And in terms of some of the sentences that use GW, I suspect that they might have meant GWh anyway, but it's difficult to be sure. Indeed at one place they do refer to GWh but in a sense that they did mean GW elsewhere?

It is of course easily possible to constrain PV generation; it's simply that installed systems aren't designed with an interface to permit the network to request it. My PV system for example, clamps its generation to a 3.68 kW max despite a nameplate capability of 4 kW. You can see the 'flat top' clearly on the attached image. (I think it's quite a clever trick given I have 16 microinverters!)

Renewableuk's release has notes at the bottom giving the GWh figures (180GWh) to go with the GW figures (95GW).

Curtailing PV is not just a technical problem, it's a legal and commercial problem. There is no legislation that could force PV owners to reduce their production and forego income/CFDs/FiTs. Nor any mechanism to pay them to do so, other than voluntary time-of-export tariffs like Octopus Agile Outgoing.

Any attempt to introduce compulsory PV curtailment would be unpopular and maybe counterproductive.

Hmmm, that's weird, it pulled through the wrong quote!

I was trying to reference WillinAberdeen's Fridge Analogy

Posted By: fostertomSo that's the end of the claim that nuclear is necessary as base load - if base load can already be supplied from solar via batteries.

Posted By: tonyEr, no, that is not a logical conclusion, sorry. The sun does not always shine and batteries run flat.

Posted By: WillInAberdeenBatteries don't generate power, just delay it, to avoid waste ... We still need farms too!

Sure, but the point about solar (and wind) needing baseload as well, is not about renewables' eventual capacity (power) but about their intermittency forever. But now, apparently, as battery capacity is growing even faster (?) than renewable generation, looks like intermittency is becoming an obsolete problem - batteries on the way to supplying all the continuity necessary, for whatever duration is necessary.

So save the squillions on nuclear, which only lumbers the grid with high costs per unit for decades, which could otherwise free-fall as renewables get cheaper and cheaper. Off-grid/microgrids will become a no-brainer, unless govt outlaws them when no one wants to buy grid electricity any more and the investors in nuclear can't be paid their contracted due.

I wonder (i.e. I haven't gone looking yet to find out) whether National Grid ESO have investigated the feasibility of putting some large battery storage plants near to major consumption areas, rather than the current practice of putting them near large generators? That way it seems possible they might be able to use the network more consistently to deliver energy to where it is needed 24 hours a day rather than have to size the network to meet peak demand.

Somewhat related to this topic, and important I feel, is a thread at another place https://renewableheatinghub.co.uk/forums/electricity-providers/incorrect-billing-of-customers-with-a-smart-meter which I hope it's OK to post a link to.

@DamonHD - what is "it"? FWIW there's a lot of fuss here in Suffolk about proposed upgrades to generation - Sizewell C - and transmission - both offshore and onshore pylons - that appear to be driving ahead despite a lot of local objections.

All those PV issues apply to wind turbines. They were sorted.

Big wind farms are connected to the transmission network, not the distribution network. They agree to the technical and contractual arrangements for curtailment as part of their application for a connection to the TN. The 'grid code' (part of the Electricity Act) sets out all the regulations for this.

PV is almost universally connected to the Distribution network and not subject to curtailment.

Small wind farms on the DN are also not subject to curtailment (I think Ripple are an example).

It seems to me that several people are talking about the differences between large generation sites and small (domestic?) sites, and the differences between pre-existing sites and new sites, rather than the differences between PV and wind sites. So I suppose the differences in points of view are smaller than they might appear.

Few other things :

Curtailment isn't a bad thing, it is cheaper to overbuild renewable capacity and curtail it sometimes, than to underbuild and need more fossil backup.

Most curtailment in the UK happens because of transmission constraints between Scotland and SE England. New transmission lines are planned, but takes years to get past local objections. Mostly this is wind power, which peaks over multi day cycles (vs batteries which work on 2-4 hours cycles). So longer duration storage is needed (pumped storage) which also takes years to plan/build. Batteries can be built fast ( don't get planning objections) so can help a bit in the short term.

The previous and present subsidy systems (FiT, ROC, CfD, SEG) all pay a fixed £ for each kWh, irrespective of what time of day it is delivered. So owners maximise outputs, even when the grid is oversupplied and power prices are low. Needs to change to subsidise more production at times when power is actually needed, eg west-facing PV with integrated batteries.

The Royal Society of scientists did a big report on power storage, they looked at UK using only wind+solar with different storage durations and think it is doable by storing hydrogen underground long term. Would also work with some nuclear and/or CCS in the mix, but slightly more expensive. They found records of some years much windier than others (eg 2021 was poor) so we’ll need inter-year energy stores, as well as seasonal, weekly and hourly storages. Batteries help, but only for short-duration hourly storage.

https://royalsociety.org/news-resources/projects/low-carbon-energy-programme/large-scale-electricity-storage/