Energy blackouts

[Mr. Fox]

A 10MWh Li-Ion UPS for £20m! Isn't that £2000 per kWh? Yikes.

Just plucking the '6,000 (homes for 1.5 hours at peak times)' figure, it would take another 4000+ units and £80bn+ to roll out. Where on Earth would we ever find that sort of money?

Good spot, em... Thanks.

[clv101]

In a 'blackout' situation having just few hundred watt supply would be hugely more useful than 0W. On a tenth of our normal supply, we can still run lighting, laptop, phone, refrigeration etc... with a bit of care.

This is where I see smart meters having a lot of potential. If there's a serious power shortage, busting residential areas down to 3 amps is just a bit inconvenient (no electric showers or ovens...) but surviving for a few days on low supply isn't likely to have the same societal impacts as a full blown blackout.

[fuzzy]

You can't put a current limit to throttle back supply, it doesn't work like that. You could have 2 supply fuses and switch between them in time of shortage. One could be a self resetting thermal type set to 3 amps so if you used more power it trips then after it cools you have the supply back. It would be more sensible to mandate that appliances in the EU will have remote timing capability. This could be washing/freezers etc for off peak times.

[adam2]

A 10MWh Li-Ion UPS for £20m! Isn't that £2000 per kWh? Yikes.

Just plucking the '6,000 (homes for 1.5 hours at peak times)' figure, it would take another 4000+ units and £80bn+ to roll out. Where on Earth would we ever find that sort of money?

Good spot, em... Thanks.

Yes, a capital cost of £2,000 per KWH of storage, presume that the battery is half that cost with the remainder being other equipment and the premises.
If the battery lasts 1000 cycles and costs £10 million to replace, then energy from discharging the battery costs £1 a KWH.
Add to that the cost of the rest of the facility, another £10 million but spread over a much longer time, perhaps 10,000 cycles, that would come to 10 pence a unit.
The cost of the energy to charge the battery might be another 10 pence a KWH.

So that comes to £1.20 a KWH, plus rates, premises maintenance, staff, servicing, and repairs.

[Tarrel]

I worked out the other day that, on an average of 12000 miles per year and 45 mpg, the average motorist stands to save around £300 a year based on a comparison of petrol costs today vs. a year ago.

That £300 would buy a couple of cheap leisure batteries, a 300W inverter, a mains battery charger and a multi-gang extension lead. If everyone did that, we'd all have the ability to maintain essential electrical supply in the event of periodic outages caused, perhaps, by aging equipment failure, rota power cuts when the wind isn't blowing or geopolitically-induced fuel shortages. (Or just bad weather he says, with an eye on tomorrow night!)

[clv101]

That £300 would buy a couple of cheap leisure batteries, a 300W inverter, a mains battery charger and a multi-gang extension lead.

I think a 'domestic' UPS for essential stuff is a very good idea.

[Mr. Fox]

So that comes to £1.20 a KWH...

Jeez... not even bedsit landladies in Portsmouth charge that much, Adam.

You can't put a current limit to throttle back supply, it doesn't work like that. You could have 2 supply fuses and switch between them in time of shortage. One could be a self resetting thermal type set to 3 amps so if you used more power it trips then after it cools you have the supply back. It would be more sensible to mandate that appliances in the EU will have remote timing capability. This could be washing/freezers etc for off peak times.

You can see the full 'smart meter' spec here. Details on the exact nature of how it will work in practice are sketchy, but technically it boils down to:

A current sensor telling a computer what you're drawing, then the computer deciding whether to disconnect you or not, like some judgemental little power goblin.

I can imagine something like those old 'coded' car stereos that double the lock-out time every time you enter the wrong numbers. Here's your kW, go over that and you get a 10 sec disconnect, do it again and it's 20 secs dark, then 40... It's light or TV, peasant. Got that?

More likely, it'll start with the provision in the contract to charge you extortionate penalties for transgression. A bit like phone companies, except with spying on your toaster usage patterns (and the power of life and death).

This 'ere is from 'Consumer Focus', who became 'Consumer Futures' before ironically get austeritied out of existence last year:

Does a smart meter allow my energy supplier to limit my energy use (also known as ‘load limiting’)?

None of the energy suppliers are currently using ‘load limiting’.

Energy suppliers have committed not to use load limiting without notifying Consumer Focus and Ofgem. Ofgem considers that this could have the same impact as disconnecting your supply, and introduced new consumer protection rules around this in October 2011. Please contact the Citizens Advice consumer service on 08454 04 05 06 if you or someone you know has been offered or has experience of their load being limited. You can also contact the Citizens Advice consumer service on 0208 1850 710 (English language) or 0208 1850 717 (Welsh language).

What is technically possible with a smart meter

At present most of us can use as much electricity as we want, provided we can afford to pay for it. Smart meters will make it possible in the future for energy suppliers to offer cheaper tariffs with a ‘load limit’ or to use this function if you fall into debt.

If you have this type of tariff your energy supplier could limit the amount of electricity that you can use at any one time eg they could supply only a very low level of electricity, for example enough electricity to power lights, a fridge and TV. Your energy supplier could also, in agreement with you, put a cap on the amount of energy you use in a given period eg per day or week. This is called ‘load limiting’. As explained above, none of the energy suppliers are currently using load limiting.

Consumer Focus

It's like: you know they've got a gun, but they're not waving it around yet, so it's all ok... they're 'committed' to not using it - meanwhile they're drawing a bead on the less-rich. Still, I agree that 'smart' meters would be very useful in 'black start' situations, or maybe for giving 'rota load disconnections' that personal touch.

[adam2]

You can't put a current limit to throttle back supply, it doesn't work like that. You could have 2 supply fuses and switch between them in time of shortage. One could be a self resetting thermal type set to 3 amps so if you used more power it trips then after it cools you have the supply back. It would be more sensible to mandate that appliances in the EU will have remote timing capability. This could be washing/freezers etc for off peak times.

This is true.
Smart meters don't have any facility to limit or control the amount of electricity used, nor could any such facility be readily introduced.

Any sort of automatic thermal cutout would be very destructive to some appliances if it continually cycled on/off as would happen if say a water heater was on left on in empty premises.

Whilst in theory load could be partially controlled by charging a punitive rate at times of shortage, but in practice I fear that most consumers would use as much electricity as before and complain about--
"fat cat utility bosses charging more just when families most need it"
"hugely overcharging without warning or consultation"
"falling into debt as a result of unexpected surcharges, worse than banks"
"no one warned me"
"why should I pay what looks like a fine, for going out and leaving the washing machine on"

And limiting the load to as little as 3 amps might not help much if everybody used the full 3 amps at the same time. Remember that the average load per house is only about 5 amps now !
The PEAK load per house can be 60 or 100 amps, but not normally for long, so the average is surprisingly low.

[Tarrel]

Well, it can't have escaped people's notice, but we've had some pretty rough weather up in this neck of the woods the last few days. This led to a four hour power-outage on Friday evening, which was a good test of our hastily cobbled together back up system.

System consists of:
75 Ah leisure battery - GoOutdoors sale 60 quid
300 W inverter - same source
Lidl smart charger - 15 quid
Extension lead reel with four sockets - B&Q

Plus: wood fired Rayburn for cooking, water heating and local space heating

We have a floor-standing column lamp with a full length paper shade, lit by 3 x candle bulbs, for which we have substituted 4 W LEDs. This, together with a table lamp (also LED) provides a high level of light, also relatively diffuse, for lighting the kitchen / dining area. The inverter was used to power these and the internet router.

Lessons learned:
1. The inverter fan is noisy, so it could do with being outside or in another room
2. Without power to the central heating pump, the water in our thermal store started to boil so I had to cool it down by drawing water for a bath (no great hardship, but a waste to some extent)
3. Although the lighting was adequate, it was no substitute for the overhead lighting provided by the LED-equipped halogen GU10s in the room (well, not for my ageing eyes, anyway).

So, I need to find a way of providing battery back-up to the central heating pump and overhead lights. Generally though, no high drama and business in the home carried on pretty much uninterrupted.

[biffvernon]

Nice to see wind producing more electricity than gas tonight.
Wind = 16% Gas=12%
http://gridwatch.templar.co.uk/index.php

[emordnilap]

So, I need to find a way of providing battery back-up to the central heating pump and overhead lights.

That's one of my concerns too; the other concern is our deep well pump. We have power outages every year around this time and I always say I'm going to sort out those two 'problem' requirements - and then, year on year, it gets put on the long finger. I will regret this. Keep us informed as to your solution.

Generally though, no high drama and business in the home carried on pretty much uninterrupted.

Yes.

[adam2]

Well, it can't have escaped people's notice, but we've had some pretty rough weather up in this neck of the woods the last few days. This led to a four hour power-outage on Friday evening, which was a good test of our hastily cobbled together back up system.

System consists of:
75 Ah leisure battery - GoOutdoors sale 60 quid
300 W inverter - same source
Lidl smart charger - 15 quid
Extension lead reel with four sockets - B&Q

Plus: wood fired Rayburn for cooking, water heating and local space heating

We have a floor-standing column lamp with a full length paper shade, lit by 3 x candle bulbs, for which we have substituted 4 W LEDs. This, together with a table lamp (also LED) provides a high level of light, also relatively diffuse, for lighting the wearedodgy / dining area. The inverter was used to power these and the internet router.

Lessons learned:
1. The inverter fan is noisy, so it could do with being outside or in another room
2. Without power to the central heating pump, the water in our thermal store started to boil so I had to cool it down by drawing water for a bath (no great hardship, but a waste to some extent)
3. Although the lighting was adequate, it was no substitute for the overhead lighting provided by the LED-equipped halogen GU10s in the room (well, not for my ageing eyes, anyway).

So, I need to find a way of providing battery back-up to the central heating pump and overhead lights. Generally though, no high drama and business in the home carried on pretty much uninterrupted.

As regards the lighting problem, it might be worth changing some or all of the 240 volt GU10 lamps to 12 volt LED MR16 types. These could be supplied from the mains normally via suitable transformer, with manual or automatic changeover to the 12 volt battery supply when needed.

Alternatively, could the existing lights be left as is, but be supplemented with 12 volt lighting mounted under cupboards so as to light working surfaces.

[Tarrel]

As regards the lighting problem, it might be worth changing some or all of the 240 volt GU10 lamps to 12 volt LED MR16 types. These could be supplied from the mains normally via suitable transformer, with manual or automatic changeover to the 12 volt battery supply when needed.

Hadn't thought of that. Good idea. It avoids what I'm trying to avoid, which is to have an additional and separate 12V system permanently in place and potentially looking unsightly.

Alternatively, could the existing lights be left as is, but be supplemented with 12 volt lighting mounted under cupboards so as to light working surfaces.

Yes, I've been thinking along similar lines. It would be an elegant solution that puts light just where it's needed.

Thanks!

[Mr. Fox]

You can't put a current limit to throttle back supply, it doesn't work like that. You could have 2 supply fuses and switch between them in time of shortage. One could be a self resetting thermal type set to 3 amps so if you used more power it trips then after it cools you have the supply back. It would be more sensible to mandate that appliances in the EU will have remote timing capability. This could be washing/freezers etc for off peak times.

This is true.
Smart meters don't have any facility to limit or control the amount of electricity used, nor could any such facility be readily introduced.

You'd better tell DECC, then - they appear to have made such capability mandatory for all smart meters in the UK!

5.5.6 Load limiting
ESME shall be capable of determining when the Active Power import (5.7.5.4) is above, for the Load Limit Period (5.7.4.19), the Load Limit Power Threshold (5.7.4.20) and on such an occurrence ESME shall be capable of:

i. generating an entry to that effect in the Event Log (5.7.5.16);
ii. generating and sending an Alert to that effect via its HAN Interface and its User Interface;
iii. counting the number of such occurrences in the Load Limit Counter (5.7.5.18 ); and
iv. ignoring the Non-Disablement Calendar (5.7.4.30) and Disabling the Supply in circumstances where the Load Limit Supply State (5.7.4.22) is configured to require Disablement, and then:
a. immediately Arming the Supply such that it can be Enabled as set-out in section 5.6.2.5;
b. after the Load Limit Restoration Period (5.7.4.21) has elapsed Enabling the Supply, and setting the Load Limit Supply State (5.7.4.22) to unchanged; and
c. displaying any such change in the Supply State (5.7.5.32) on its User Interface and generating and sending an Alert indicating the change in state via its HAN Interface.

SMETS2 (smart metering equipment technical specifications)

Judgemental little power goblins... with their little goblinny hands on the switch. They're coming for us, I tell ya... none of yous will believe me until it's too late!

[adam2]

I thought it worth reviving this very old thread in view of a new report that implies that the situation may have got worse.

I refer here NOT to a possible shortage of generating capacity, that is unlikely to do anything worse than rota power cuts at times of high demand.
"surviving" a 3 hour rota power cut is trivial for most of us.

I refer here to the perhaps growing risk of a total grid shutdown, and the increasing difficulties in "black starting" generating plant.

Nuclear plant is not suitable and requires external power.
Wind and solar are not suitable.
Neither are HVDC interconnectors to neighbouring nations.

So that leaves us with

Hydroelectric plant is generally suitable, the very limited power needed is easily obtained from batteries or a diesel generator.

SOME but not all coal burning capacity can be black started, not quickly though. Run up times vary from a few hours if still hot and fully staffed, up to 48 hours from "cold and dark" And perhaps some days if staff are not on site and can not attend promptly due to traffic congestion or shortage of road fuel or closure of public transport.

SOME gas turbine plant can be black started, from batteries or air bottles, but not all.
Diesel engines usually start from batteries or air bottles.

Most diesel engines are too small to be of much use unless a number are available.

Under emergency black start conditions the frequency is permitted to vary a lot more than under normal conditions, from 47 cycles up to 52 cycles IIRC.
Requirements for black start plant include the ability to perform several sequential starts in case the re-energised part of the grid trips again, The ability to accept sudden block loading, and sufficient fuel stored on site for 7 days operation.