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UK Electricity Generation
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PS_RalphW



Joined: 24 Nov 2005
Posts: 5267
Location: Cambridge

PostPosted: Wed Sep 28, 2016 8:55 pm    Post subject: Reply with quote

Ice cars are not more reliable. They have far more moving parts and far more to go wrong. EV charging infrastructure is not currently reliable, but it is improving.

https://www.theguardian.com/environment/climate-consensus-97-per-cent/2016/sep/28/new-mit-app-check-if-your-car-meets-climate-targets

An app/web page to see what the total cost of ownership is for a (US) car based on many parameters. Of course it does not put a price on range or pollution.

Thinking about powering the UK car fleet from renewables, the batteries in 30 million cars at 50KWh each represent 1.5 TWh of storage. It represents 5 days of average consumption for each car, so allowing half of that to be available in the form of deferred demand for charging, it gives 2.5 days cover for zero wind and solar supply in the winter, at the current level of supply. All it would need would be a smart controller and the car plugged in overnight.

Getting 30 million charging points at 500 -1000 each will not be cheap, and will in the longer term be a limiting factor in EV take-up unless driverless rental on demand becomes the norm.
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adam2
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Joined: 02 Jul 2007
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Location: North Somerset

PostPosted: Wed Sep 28, 2016 9:21 pm    Post subject: Reply with quote

A basic charging point need not be that costly.

A medium fast charger would need a 32 amp single phase supply, that should not cost much more than 150 to install in most cases.

A slow charger limited to 10 amps input should effectively cost nothing to install, it simply plugs in to an existing socket outlet.

10 amps input for 12 hours would in practice fully charge most EV batteries, it would be about 25KWH.
Whilst many EV batteries are, or are expected to exceed 25KWH, they would not normally be fully discharged every day.

Anyone who regularly fully or nearly fully discharges an EV battery will be spending so much on new batteries and on electricity, that the cost of installing a 32 amp outlet is by comparison affordable.

I fear that the electrical contracting industry and HMG are trying make charging an EV an unduly costly and complicated operation.

IMHO, a basic EV not driven to the limit every day should be chargeable by plugging it in like any other appliance.

A mid range EV in fairly intensive use should be chargeable by simply plugging it in to a single phase 32 amp socket outlet.
In most homes, 32 amps is about the limit anyway without a supply upgrade. Even 32 amps might be marginal in some homes.
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vtsnowedin



Joined: 07 Jan 2011
Posts: 4281
Location: New England ,Chelsea Vermont

PostPosted: Thu Sep 29, 2016 3:24 am    Post subject: Reply with quote

adam2 wrote:

In most homes, 32 amps is about the limit anyway without a supply upgrade. Even 32 amps might be marginal in some homes.

I find that surprising. I grew up in a house with a 60 Amp entrance that had four 15 amp screw in fuses plus two (IIRC) 30 amp cartridge fuses, one for the electric range and one for the barn circuit which was 100 yards across the yard from the house. They added another circuit for a clothes dryer and yet another for an electric hot water heater as things progressed but the in feed from the meter was always at least 60 amps and more likely 100 amps and never upgraded from what was installed in 1945. When I built new I started with a 200 amp entrance and still have plenty of room in the circuit breaker panel for additional circuits.
That you have houses that can't rely on more then 32 amps supply boggles the mind.
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johnhemming2



Joined: 30 Jun 2015
Posts: 1976

PostPosted: Thu Sep 29, 2016 7:05 am    Post subject: Reply with quote

My father told me a story about a domestic installation which so overloaded the supply that it used to melt snow on the drive because the supply cables were so warm.
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Peter1010



Joined: 07 Jun 2011
Posts: 44
Location: Powys

PostPosted: Thu Sep 29, 2016 7:20 am    Post subject: Reply with quote

vtsnowedin wrote:
adam2 wrote:

In most homes, 32 amps is about the limit anyway without a supply upgrade. Even 32 amps might be marginal in some homes.

I find that surprising. I grew up in a house with a 60 Amp entrance

Is this on a 110v supply or 240v supply? Anyway the fuse rating is to protect the wiring, doesnt mean that one will be able to draw up to the fuse rating, that depends on the ability of the supply to supply that much power. I remember on my dad's farm, whenever he switched on the milking machine, the initial current draw was such that the voltage dropped causing all the lights to dim for a small while until the current dropped once the motor got up to speed.
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Pepperman



Joined: 10 Oct 2010
Posts: 759

PostPosted: Thu Sep 29, 2016 7:58 am    Post subject: Reply with quote

clv101 wrote:
A key take home is that our electricity use peaked over a decade ago and has fallen a lot (twice Hinkley's C expected output). This is despite population and GDP growth. I'm often surprised by meeting clued-up, energy literate people that just seem to assume electricity demand has been and will continue to increase - it just ain't so.


The current move towards electrification of heat as well as electric vehicles could change that.

There are serious moves afoot to electrify pretty much evreything. Personally I can't see it happening in heat but it wll happen in transportation so you can expect about a 30% uptick in annual demand as a result (a 30% increase to electrify the bulk of transport is a pretty good deal imo, especially given the massive energy saving you get from not burning fuel in a heat engine at 25% efficiency).

There are still big gains to be had in lighting and appliance demand which should come close to that so I don't see electric transportation being a significant burden.

It's heat that is the problem and I can't see any solution. The cost of heating system replacement, the burden on the grid, the idle generating capacity when it's not cold - all of these and more will conspire against large scale electrification of heat, especially if you're aiming for a grid largely supplied by renewables.

We're going to need to come up with another solution for heat.
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Pepperman



Joined: 10 Oct 2010
Posts: 759

PostPosted: Thu Sep 29, 2016 8:07 am    Post subject: Reply with quote

As Ralph points out fully useable electric cars are here, now and lots more are on the way. Range has jumped from <100 to >200 miles in one generation (good for something like 99.9% of trips) and already there are vehicles in the offing with a 300 mile range in the next generation (a bit before 2020). A growing fast charger network means that pounding up and down the country in them will be eminently feasible. People are already doing it in Teslas.

(Tthe speed at which range has increased has taken me completely by surprise - I have long been arguing with people who diss EVs that PHEVs will be a needed solution for a long time but this is rapidly becoming untrue)

Fast charging is also a great solution for people who live in flats or otherwise don't have off street parking and want an EV.

But the potential for grid disruption is huge. We're going to need to shift EV charging to time of use tariffs soon to encourage charging away from the peak and preferably overnight as much as possible.
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Little John



Joined: 08 Mar 2008
Posts: 5667
Location: UK

PostPosted: Thu Sep 29, 2016 8:38 am    Post subject: Reply with quote

The World's farmlands are knackered. All of the ancient freshwater aquifers are rapidly depleting. The climate is rapidly heating up and we are living through the biggest mass extinction event since the end of the Permian.

Underneath all of this, because it is the driver of all the others, is a massive overshoot of the human population, the vast majority of whom naturally wish to engage in the very industrial lifestyle that has led us to this impasse. Not that it matters much now anyway, since there are now so many people damage is occurring irrespective of industrialisation.

So, what do humans need to do? They need to change direction. Radically. What are humans doing? Devising ever more ingenious ways to carry on in the same direction as before. But, the destination will be the same and will be even worse than it might have been.

Technology will not save us or the rest of life on earth.
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adam2
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Joined: 02 Jul 2007
Posts: 6218
Location: North Somerset

PostPosted: Thu Sep 29, 2016 9:18 am    Post subject: Reply with quote

vtsnowedin wrote:
adam2 wrote:

In most homes, 32 amps is about the limit anyway without a supply upgrade. Even 32 amps might be marginal in some homes.

I find that surprising. I grew up in a house with a 60 Amp entrance that had four 15 amp screw in fuses plus two (IIRC) 30 amp cartridge fuses, one for the electric range and one for the barn circuit which was 100 yards across the yard from the house. They added another circuit for a clothes dryer and yet another for an electric hot water heater as things progressed but the in feed from the meter was always at least 60 amps and more likely 100 amps and never upgraded from what was installed in 1945. When I built new I started with a 200 amp entrance and still have plenty of room in the circuit breaker panel for additional circuits.
That you have houses that can't rely on more then 32 amps supply boggles the mind.


The great majority of UK homes have a single phase supply at 60 amps, 80 amps or 100 amps, 240 volts.
There a few of only 40 amps and a few three phase services but these are very rare.
In most cases I would consider that a 32 amp circuit for charging an EV is about the most that can be prudently added to an existing installation.
And even that may be marginal in a larger home with electric cooking and an electric shower.

In the USA, 100 amps is the accepted minimum for new construction and 200 amps is very common.320/400 amps is becoming more popular for larger homes.
This is normally at the USA standard of single phase, 3 wire, 120/240 volts.
So a USA service at 100 amps can supply the same amount of power as a UK 100 amp supply.
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woodburner



Joined: 06 Apr 2009
Posts: 3384

PostPosted: Thu Sep 29, 2016 9:31 am    Post subject: Reply with quote

Little John wrote:
The World's farmlands are knackered. All of the ancient freshwater aquifers are rapidly depleting. The climate is rapidly heating up and we are living through the biggest mass extinction event since the end of the Permian.

Underneath all of this, because it is the driver of all the others, is a massive overshoot of the human population, the vast majority of whom naturally wish to engage in the very industrial lifestyle that has led us to this impasse. Not that it matters much now anyway, since there are now so many people damage is occurring irrespective of industrialisation.

So, what do humans need to do? They need to change direction. Radically. What are humans doing? Devising ever more ingenious ways to carry on in the same direction as before. But, the destination will be the same and will be even worse than it might have been.

Technology will not save us or the rest of life on earth.


I agree with all you say, but I suspect fifth column may disagree at least about the state of farmland.
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Potemkin Villager



Joined: 14 Mar 2006
Posts: 782
Location: Narnia

PostPosted: Thu Sep 29, 2016 4:11 pm    Post subject: Reply with quote

Little John wrote:


So, what do humans need to do? They need to change direction. Radically. What are humans doing? Devising ever more ingenious ways to carry on in the same direction as before. But, the destination will be the same and will be even worse than it might have been.

Technology will not save us or the rest of life on earth.


Spot on LJ I couldn't agree more.

That is why we so love the mental distraction of discussing the fine details and technical minutiae of glossy high tech schemes without considering if they really make sense in the context of the greater scheme of things.

Whether we arrive by ICE or EV the destination surely remains no better. Just because you can do something in itself is not a good reason to charge ahead and do it.
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vtsnowedin



Joined: 07 Jan 2011
Posts: 4281
Location: New England ,Chelsea Vermont

PostPosted: Thu Sep 29, 2016 7:49 pm    Post subject: Reply with quote

Peter1010 wrote:
vtsnowedin wrote:
adam2 wrote:

In most homes, 32 amps is about the limit anyway without a supply upgrade. Even 32 amps might be marginal in some homes.

I find that surprising. I grew up in a house with a 60 Amp entrance

Is this on a 110v supply or 240v supply?

240 volt to the fuse panel and on to the electric, range and water heater as well as the clothes dryer. The 15 amp fuses were for 110 volt circuits which is the USA standard for lighting and small appliances. You could blow a 15 amp fuse by plugging in too many appliances at once but the breakers for the 240 volt circuits never went. The electrician that wired the old farmhouse used copper 14 gauge wire and soldered all the connections. It all preformed very well over the years.
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