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Smart Energy Usage


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#1 Alphonsox

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Posted 04 March 2016 - 08:32 AM

Potentially interesting report out today from the Nation Infrastructure Commission. It proposes the use of technology to make better use of the energy we have rather than generating more. A bit "pie in the sky" at first glance but at least some sign of alternative thinking.

http://www.bbc.co.uk...siness-35722324

#2 ProDave

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Posted 04 March 2016 - 08:43 AM

I recall one sunny Sunday for some reason we were having Sunday dinner in the middle of the day, and that's the one meal I always cook.

The solar PV was generating nicely, the dishwasher and Oven was on.

I recall every time the themostat on the oven clicked on, I went and stopped the dishwasher, and re started it when the oven thermostat clicked off. All very OCD but I thought "I wonder what it would take to automate this" and concluided far too much on that level.

I can see a well insulated freezer perhaps being able to avoid using power for an hour or 2 if "told to"?.

#3 DamonHD

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Posted 04 March 2016 - 08:54 AM

Actually, it really wouldn't be much effort if manufacturers integrated support into goods such as washing machines and dishwashers which can simply defer heating water for a little while while still using the mechanical action to continue cleaning. And, yes, stored 'cold' is another good one:

http://www.earth.org...mand-ideas.html

I estimated several GW of available 'virtual power station' in the UK from household devices alone:

http://www.earth.org...mand-value.html

Rgds

Damon

#4 SteamyTea

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Posted 04 March 2016 - 09:03 AM

Not really a technical issue any more, more financial and political.
The best method to get something done politically would be scheduled power cuts.

#5 DamonHD

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Posted 04 March 2016 - 09:06 AM

Oh, unscheduled ones might do the trick too, preferably caused, as last time, by big nuke and coal tripping off-line so we don't get into a foaming-at-the-mouth side battle about "wind is unreliable" or related tosh...

Rgds

Damon

#6 SteamyTea

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Posted 04 March 2016 - 09:41 AM

:D

Just had a quick re-read of your bit about turning things off by using grid frequency. I am not so sure that it can be done on frequency as the national grid coordinates the ramp up and ramp down times to suit demand. This often means that there are times when frequency is high during low demand times (early morning getting ready for the kettles and showers) and late evening the frequency can be lower as things 'wind down for the night'.

Edited by SteamyTea, 04 March 2016 - 09:49 AM.


#7 DamonHD

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Posted 04 March 2016 - 10:51 AM

This sort of stuff absolutely can be done just on frequency to the best of my knowledge, as some of the faster tiers of grid support are too quick for any other reasonable trigger such as comms over the Internet or GSM. NG has a long list, including specs, and I think another even faster tier is being introduced. Please note the actual stats on number of samples and distance of excursion from nominal 50Hz.

Rgds

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Edited by DamonHD, 04 March 2016 - 10:52 AM.


#8 SteamyTea

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Posted 04 March 2016 - 11:20 AM

I shall have to take a relook at it, but when I was doing my ResM, I mentioned it as a problem and a few 'experts' agreed with me and said that it had not occurred to them.
Not an insurmountable problem as the NG knows when it is ramping up and down and can look for, and act on, variation within those timeslots.
But it is not a simple model, like a generator and fractional loads, it is fractional generation and fractional loads, which is harder to manage.

#9 Alphonsox

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Posted 04 March 2016 - 08:24 PM

For those having problems sleeping, here's the full report...

https://www.gov.uk/g..._Report_web.pdf

#10 tonyshouse

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Posted 04 March 2016 - 09:51 PM

I reckon that wifi or the web could control any appliance via its plug.

Switching off freezers during peak for me is a must do thing

I would have saved us building a new power station had we been quicker off the maths

Edited by tonyshouse, 05 March 2016 - 08:55 AM.


#11 SteamyTea

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Posted 05 March 2016 - 05:56 AM

Probably save more by limiting the power of electric showers to 7 kW,

#12 billt

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Posted 05 March 2016 - 09:45 AM

View Posttonyshouse, on 04 March 2016 - 09:51 PM, said:

Switching off freezers during peak for me is a must do thing

Why? Do you have the most inefficient freezer you could buy 30 years ago?

We have 2 freezers. One of them consumes 50W for about 10 minutes every hour, the other consumes under 30W for about 20 minutes every hour. Turning them on and off is going to achieve absolutely nothing in terms of demand reduction.

#13 Alphonsox

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Posted 05 March 2016 - 10:19 AM

Multiply your average consumption (5-10W) by the millions of freezers installed in the country and you'll start to see a demand reduction

#14 ProDave

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Posted 05 March 2016 - 10:30 AM

View PostSteamyTea, on 05 March 2016 - 05:56 AM, said:

Probably save more by limiting the power of electric showers to 7 kW,
I'm surprised the EU has not done that already. It must be in their sights?

#15 SteamyTea

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Posted 05 March 2016 - 10:32 AM

I am with BillT here. Modern fridges use such little power, even if multiplied by 50 million, they don/t make a large enough difference.
If you have a look at Damon's Grid Intensity webpage:
http://www.earth.org...ntensityGB.html
At 18:00 last night, we used 46GWh of electricity.
If we say a fridge uses 10W when running, and there are 50 million of them, then that is 0.083 GWh.
Or 0.2 of generation capacity.

#16 Alphonsox

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Posted 05 March 2016 - 10:48 AM

The gain here is in small increments - 500MW (10Wx 50million freezers) is a medium sized gas fired power station and it's instantaneous - However I take the point the freezers aren't the solution, the big bang for buck will be using electric cars as storage.

#17 DamonHD

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Posted 05 March 2016 - 11:35 AM

Turning off all the UK's fridges and freezers for a short while if the grid was in trouble (or at peak demand times) would save about 2GW, likewise for heating circulation pumps another 1GW.

The numbers are HUGE. Those two alone would match the output of Hinkley Point C.

The issue here is to shift consumption away from peak times or when the grid is having a bad moment AS WELL AS reducing overall consumption (eg better freezers). The effect will be to reduce the amount of explicit reserves and the maximum system capacity, and thus costs.

Rgds

Damon

Edited by joiner, 05 March 2016 - 11:42 AM.
"bad" for "bade"


#18 jsharris

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Posted 05 March 2016 - 11:49 AM

Fitting even a modest PV system can "automatically" reduce quite a lot of the daytime small loads to near-zero without the need for any smart systems intervention. It's rare for our PV to not cover the house background load for most of the daylight hours, and our background loads are higher than most, as we have a 30 W sewage treatment plant and a 30 W UV water disinfection unit running 24/7. The UFH circulation pump runs at around 20W and is on from 07:00 to 20:00 each day, and left off over night.

AFAICS, most of the grid problems occur during the late afternoon/early evening, so greater take-up of PV would probably resolve this for much of the year. A bit of buffer storage to tide the grid over the couple of hours after PV generation stops whilst demand is still high would probably fix things, and from the scale of it it looks as if a couple more pumped storage schemes might achieve this, if we had a fair bit more PV.

I've been looking at what it would take to get our house totally off-grid, and it really comes down to having around another couple of kWp of PV plus around 20 to 30 kWh of storage. Not realistically economical for us at the moment, but it may well be in the next few years, I'm not sure that it's the right approach to take, though, and can't help but wonder if small scale community energy storage, grid connected, might not make more sense. The grid is pretty robust at its core, the weak areas seem to be at the ends of the distribution network. Buffer those with storage and the result is more beneficial than building a couple more Dinorwic scale storage systems.

#19 DamonHD

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Posted 05 March 2016 - 12:08 PM

JSH: look at "flattening the duck": http://www.vox.com/2...enewable-energy

It won't be quite the same in the UK as in CA, but it's one reason why when I get my hands on a SunampPV I shall have it only draw between (say) 11 and 4, in particular to spill whatever is possible to grid as peak demand ramps up starting at 4pm.

Rgds

Damon

#20 Alphonsox

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Posted 05 March 2016 - 12:10 PM

The local energy storage solution is well underway. There are an ever increasing number of electric cars sat idle at the time of highest grid demand most of which will be partially charged. There is a lot of talk going on between the car manufacturers and grid companies to get access to this stored energy (one of the reasons they want to put radio links into the changing stations). You will effectively agree to "lend" power to the grid from your car batteries which will be replenished overnight when demand falls.